Center form submit buttons HTML / CSS
Try this :
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<head>
<style type="text/css">
#btn_s{
width:100px;
}
#btn_i {
width:125px;
}
#formbox {
width:400px;
margin:auto 0;
text-align: center;
}
</style>
</head>
<body>
<form method="post" action="">
<div id="formbox">
<input value="Search" title="Search" type="submit" id="btn_s">
<input value="I'm Feeling Lucky" title="I'm Feeling Lucky" name="lucky" type="submit" id="btn_i">
</div>
</form>
</body>
This has 2 examples, you can use the one that fits best in your situation.
- use
text-align:centeron the parent container, or create a container for this. - if the container has to have a fixed size, use
autoleft and right margins to center it in the parent container.
note that auto is used with single blocks to center them in the parent space by distrubuting the empty space to the left and right.
How to align a div inside td element using CSS class
I cannot help you much without a small (possibly reduced) snippit of the problem. If the problem is what I think it is then it's because a div by default takes up 100% width, and as such cannot be aligned.
What you may be after is to align the inline elements inside the div (such as text) with text-align:center; otherwise you may consider setting the div to display:inline-block;
If you do go down the inline-block route then you may have to consider my favorite IE hack.
width:100px;
display:inline-block;
zoom:1; //IE only
*display:inline; //IE only
Happy Coding :)
How to position a div in the middle of the screen when the page is bigger than the screen
Short answer, Just add position:fixed and that will solve your problem
align text center with android
Adding android:gravity="center" in your TextView will do the trick (be the parent layout is Relative/Linear)!
Also, you should avoid using dp for font size. Use sp instead.
Center text in table cell
I would recommend using CSS for this. You should create a CSS rule to enforce the centering, for example:
.ui-helper-center {
text-align: center;
}
And then add the ui-helper-center class to the table cells for which you wish to control the alignment:
<td class="ui-helper-center">Content</td>
EDIT: Since this answer was accepted, I felt obligated to edit out the parts that caused a flame-war in the comments, and to not promote poor and outdated practices.
See Gabe's answer for how to include the CSS rule into your page.
Center the nav in Twitter Bootstrap
http://www.bootply.com/3iSOTAyumP in this example the button for collapse was not clickable because the .navbar-brand was in front.
http://www.bootply.com/RfnEgu45qR there is an updated version where the collapse buttons is actually clickable.
Center Plot title in ggplot2
If you are working a lot with graphs and ggplot, you might be tired to add the theme() each time. If you don't want to change the default theme as suggested earlier, you may find easier to create your own personal theme.
personal_theme = theme(plot.title =
element_text(hjust = 0.5))
Say you have multiple graphs, p1, p2 and p3, just add personal_theme to them.
p1 + personal_theme
p2 + personal_theme
p3 + personal_theme
dat <- data.frame(
time = factor(c("Lunch","Dinner"),
levels=c("Lunch","Dinner")),
total_bill = c(14.89, 17.23)
)
p1 = ggplot(data=dat, aes(x=time, y=total_bill,
fill=time)) +
geom_bar(colour="black", fill="#DD8888",
width=.8, stat="identity") +
guides(fill=FALSE) +
xlab("Time of day") + ylab("Total bill") +
ggtitle("Average bill for 2 people")
p1 + personal_theme
Center fixed div with dynamic width (CSS)
<div id="container">
<div id="some_kind_of_popup">
center me
</div>
</div>
You'd need to wrap it in a container. here's the css
#container{
position: fixed;
top: 100px;
width: 100%;
text-align: center;
}
#some_kind_of_popup{
display:inline-block;
width: 90%;
max-width: 900px;
min-height: 300px;
}
How to center links in HTML
One solution is to put them inside <center>, like this:
<center>
<a href="http//www.google.com">Search</a>
<a href="Contact Us">Contact Us</a>
</center>
I've also created a jsfiddle for you: https://jsfiddle.net/9acgLf8e/
Make child visible outside an overflow:hidden parent
This is an old question but encountered it myself.
I have semi-solutions that work situational for the former question("Children visible in overflow:hidden parent")
If the parent div does not need to be position:relative, simply set the children styles to visibility:visible.
If the parent div does need to be position:relative, the only way possible I found to show the children was position:fixed. This worked for me in my situation luckily enough but I would imagine it wouldn't work in others.
Here is a crappy example just post into a html file to view.
<div style="background: #ff00ff; overflow: hidden; width: 500px; height: 500px; position: relative;">
<div style="background: #ff0000;position: fixed; top: 10px; left: 10px;">asd
<div style="background: #00ffff; width: 200px; overflow: visible; position: absolute; visibility: visible; clear:both; height: 1000px; top: 100px; left: 10px;"> a</div>
</div>
</div>
How to center a (background) image within a div?
Use background-position:
background-position: 50% 50%;
Center Contents of Bootstrap row container
For Bootstrap 4, use the below code:
<div class="mx-auto" style="width: 200px;">
Centered element
</div>
Ref: https://getbootstrap.com/docs/4.0/utilities/spacing/#horizontal-centering
Button Center CSS
I realize this is a very old question, but I stumbled across this problem today and I got it to work with
<div style="text-align:center;">
<button>button1</button>
<button>button2</button>
</div>
Cheers, Mark
center aligning a fixed position div
if you don't want to use the wrapper method. then you can do this:
.fixed_center_div {
position: fixed;
width: 200px;
height: 200px;
left: 50%;
top: 50%;
margin-left: -100px; /* 50% of width */
margin-top: -100px; /* 50% of height */
}
Center button under form in bootstrap
It's working completely try this:
<div class="button pull-left" style="padding-left:40%;" >
Two HTML tables side by side, centered on the page
I found I could solve this by simply putting the two side by side tables inside of a third table that was centered. Here is the code
I added two lines of code at the top and bottom of the two existing tables
<style>_x000D_
#outer {_x000D_
text-align: center;_x000D_
}_x000D_
_x000D_
#inner {_x000D_
text-align: left;_x000D_
margin: 0 auto;_x000D_
}_x000D_
_x000D_
.t {_x000D_
float: left;_x000D_
}_x000D_
_x000D_
table {_x000D_
border: 1px solid black;_x000D_
}_x000D_
_x000D_
#clearit {_x000D_
clear: left;_x000D_
}_x000D_
</style>_x000D_
_x000D_
<div id="outer">_x000D_
_x000D_
<p>Two tables, side by side, centered together within the page.</p>_x000D_
_x000D_
<div id="inner">_x000D_
<table style="margin-left: auto; margin-right: auto;">_x000D_
<td>_x000D_
<div class="t">_x000D_
<table>_x000D_
<tr>_x000D_
<th>a</th>_x000D_
<th>b</th>_x000D_
</tr>_x000D_
<tr>_x000D_
<td>1</td>_x000D_
<td>2</td>_x000D_
</tr>_x000D_
<tr>_x000D_
<td>4</td>_x000D_
<td>9</td>_x000D_
</tr>_x000D_
<tr>_x000D_
<td>16</td>_x000D_
<td>25</td>_x000D_
</tr>_x000D_
</table>_x000D_
</div>_x000D_
_x000D_
<div class="t">_x000D_
<table>_x000D_
<tr>_x000D_
<th>a</th>_x000D_
<th>b</th>_x000D_
<th>c</th>_x000D_
</tr>_x000D_
<tr>_x000D_
<td>1</td>_x000D_
<td>2</td>_x000D_
<td>2</td>_x000D_
</tr>_x000D_
<tr>_x000D_
<td>3</td>_x000D_
<td>5</td>_x000D_
<td>15</td>_x000D_
</tr>_x000D_
<tr>_x000D_
<td>8</td>_x000D_
<td>13</td>_x000D_
<td>104</td>_x000D_
</tr>_x000D_
</table>_x000D_
</div>_x000D_
</td>_x000D_
</table>_x000D_
</div>_x000D_
<div id="clearit">all done.</div>_x000D_
</div>How to align a <div> to the middle (horizontally/width) of the page
Do you mean that you want to center it vertically or horizontally? You said you specified the
heightto 800 pixels, and wanted the div not to stretch when thewidthwas greater than that...To center horizontally, you can use the
margin: auto;attribute in CSS. Also, you'll have to make sure that thebodyandhtmlelements don't have any margin or padding:
html, body { margin: 0; padding: 0; }
#centeredDiv { margin-right: auto; margin-left: auto; width: 800px; }
How to vertically center a <span> inside a div?
Quick answer for single line span
Make the child (in this case a span) the same line-height as the parent <div>'s height
<div class="parent">
<span class="child">Yes mom, I did my homework lol</span>
</div>
You should then add the CSS rules
.parent { height: 20px; }
.child { line-height: 20px; vertical-align: middle; }
Or you can target it with a child selector
.parent { height: 20px; }
.parent > span { line-height: 20px; vertical-align: middle; }
Background on my own use of this
I ran into this similar issue where I needed to vertically center items in a mobile menu. I made the div and spans inside the same line height. Note that this is for a meteor project and therefore not using inline css ;)
HTML
<div class="international">
<span class="intlFlag">
{{flag}}
</span>
<span class="intlCurrent">
{{country}}
</span>
<span class="intlButton">
<i class="fa fa-globe"></i>
</span>
</div>
CSS (option for multiple spans in a div)
.international {
height: 42px;
}
.international > span {
line-height: 42px;
}
In this case if I just had one span I could have added the CSS rule directly to that span.
CSS (option for one specific span)
.intlFlag { line-height: 42px; }
Here is how it displayed for me
Center an element with "absolute" position and undefined width in CSS?
A simple approach that worked for me to horizontally center a block of unknown width:
<div id="wrapper">
<div id="block"></div>
</div>
#wrapper {
position: absolute;
width: 100%;
text-align: center;
}
#block {
display: inline-block;
}
A text-align property may be added to the #block ruleset to align its content independently of the alignment of the block.
This worked on recent versions of Firefox, Chrome, Internet Explorer, Edge and Safari.
How do I center floated elements?
Centering floats is easy. Just use the style for container:
.pagination{ display: table; margin: 0 auto; }
change the margin for floating elements:
.pagination a{ margin: 0 2px; }
or
.pagination a{ margin-left: 3px; }
.pagination a.first{ margin-left: 0; }
and leave the rest as it is.
It's the best solution for me to display things like menus or pagination.
Strengths:
cross-browser for any elements (blocks, list-items etc.)
simplicity
Weaknesses:
- it works only when all floating elements are in one line (which is usually ok for menus but not for galleries).
@arnaud576875 Using inline-block elements will work great (cross-browser) in this case as pagination contains just anchors (inline), no list-items or divs:
Strengths:
- works for multiline items.
Weknesses:
gaps between inline-block elements - it works the same way as a space between words. It may cause some troubles calculating the width of the container and styling margins. Gaps width isn't constant but it's browser specific (4-5px). To get rid of this gaps I would add to arnaud576875 code (not fully tested):
.pagination{ word-spacing: -1em; }
.pagination a{ word-spacing: .1em; }
it won't work in IE6/7 on block and list-items elements
Centering floating divs within another div
With Flexbox you can easily horizontally (and vertically) center floated children inside a div.
So if you have simple markup like so:
<div class="wpr">
<span></span>
<span></span>
<span></span>
<span></span>
<span></span>
</div>
with CSS:
.wpr
{
width: 400px;
height: 100px;
background: pink;
padding: 10px 30px;
}
.wpr span
{
width: 50px;
height: 50px;
background: green;
float: left; /* **children floated left** */
margin: 0 5px;
}
(This is the (expected - and undesirable) RESULT)
Now add the following rules to the wrapper:
display: flex;
justify-content: center; /* align horizontal */
and the floated children get aligned center (DEMO)
Just for fun, to get vertical alignment as well just add:
align-items: center; /* align vertical */
DEMO
Resize to fit image in div, and center horizontally and vertically
Only tested in Chrome 44.
Example: http://codepen.io/hugovk/pen/OVqBoq
HTML:
<div>
<img src="http://lorempixel.com/1600/900/">
</div>
CSS:
<style type="text/css">
img {
position: absolute;
top: 50%;
left: 50%;
transform: translateX(-50%) translateY(-50%);
max-width: 100%;
max-height: 100%;
}
</style>
center image in div with overflow hidden
Found this nice solution by MELISSA PENTA (https://www.localwisdom.com/)
HTML
<div class="wrapper">
<img src="image.jpg" />
</div>
CSS
div.wrapper {
height:200px;
line-height:200px;
overflow:hidden;
text-align:center;
width:200px;
}
div.wrapper img {
margin:-100%;
}
Center any size image in div
Used with rounded wrapper and different sized images.
CSS
.item-image {
border: 5px solid #ccc;
border-radius: 100%;
margin: 0 auto;
height: 200px;
width: 200px;
overflow: hidden;
text-align: center;
}
.item-image img {
height: 200px;
margin: -100%;
max-width: none;
width: auto;
}
Working example here codepen
Android: How to rotate a bitmap on a center point
Edited: optimized code.
public static Bitmap RotateBitmap(Bitmap source, float angle)
{
Matrix matrix = new Matrix();
matrix.postRotate(angle);
return Bitmap.createBitmap(source, 0, 0, source.getWidth(), source.getHeight(), matrix, true);
}
To get Bitmap from resources:
Bitmap source = BitmapFactory.decodeResource(this.getResources(), R.drawable.your_img);
Why is the <center> tag deprecated in HTML?
You can still use this with XHTML 1.0 Transitional and HTML 4.01 Transitional if you like. The only other way (best way, in my opinion) is with margins:
<div style="width:200px;margin:auto;">
<p>Hello World</p>
</div>
Your HTML should define the element, not govern its presentation.
CSS: Position loading indicator in the center of the screen
This is what I've done for Angular 4:
<style type="text/css">
.centered {
position: fixed;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
transform: -webkit-translate(-50%, -50%);
transform: -moz-translate(-50%, -50%);
transform: -ms-translate(-50%, -50%);
color:darkred;
}
</style>
</head>
<body>
<app-root>
<div class="centered">
<h1>Loading...</h1>
</div>
</app-root>
</body>
How to center an unordered list?
If it is possible for you to use your own list bullets
Try this:
<html>
<head>
<style type="text/css">
ul {
margin:0;
padding:0;
text-align: center;
list-style:none;
}
ul li {
padding: 2px 5px;
}
ul li:before {
content:url(http://www.un.org/en/oaj/unjs/efiling/added/images/bullet-list-icon-blue.jpg);;
}
</style>
</head>
<body>
<ul>
<li>1</li>
<li>2</li>
<li>3</li>
</ul>
</body>
</html>
Center a DIV horizontally and vertically
I do not believe there is a way to do this strictly with CSS. The reason is your "important" qualifier to the question: forcing the parent element to expand with the contents of its child.
My guess is that you will have to use some bits of JavaScript to find the height of the child, and make adjustments.
So, with this HTML:
<div class="parentElement">
<div class="childElement">
...Some Contents...
</div>
</div>
This CSS:
.parentElement {
position:relative;
width:960px;
}
.childElement {
position:absolute;
top:50%;
left:50%;
}
This jQuery might be useful:
$('.childElement').each(function(){
// determine the real dimensions of the element: http://api.jquery.com/outerWidth/
var x = $(this).outerWidth();
var y = $(this).outerHeight();
// adjust parent dimensions to fit child
if($(this).parent().height() < y) {
$(this).parent().css({height: y + 'px'});
}
// offset the child element using negative margins to "center" in both axes
$(this).css({marginTop: 0-(y/2)+'px', marginLeft: 0-(x/2)+'px'});
});
Remember to load the jQ properly, either in the body below the affected elements, or in the head inside of $(document).ready(...).
Center an item with position: relative
If you have a relatively- (or otherwise-) positioned div you can center something inside it with margin:auto
Vertical centering is a bit tricker, but possible.
RelativeLayout center vertical
This is working for me.
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/rell_main_bg"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#096d74" >
<ImageView
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true"
android:src="@drawable/img_logo_large"
android:contentDescription="@null" />
</RelativeLayout>
How to align title at center of ActionBar in default theme(Theme.Holo.Light)
solution is based on these things:
- you need to use your own class that extends Toolbar (support.v7.widget.toolbar)
- you need to override one method Toolbar#addView
what does it do:
when first time toolbar is executing #setTitle, it creates AppCompatTextView and uses it to display title text.
when the AppCompatTextView is created, toolbar (as ViewGroup), adds it into it's own hierarchy with #addView method.
also, while trying to find solution i noticed that the textview has layout width set to "wrap_content", so i decided to make it "match_parent" and assign textalignment to "center".
MyToolbar.kt, skipping unrelated stuff (constructors/imports):
class MyToolbar : Toolbar {
override fun addView(child: View, params: ViewGroup.LayoutParams) {
if (child is TextView) {
params.width = ViewGroup.LayoutParams.MATCH_PARENT
child.textAlignment= View.TEXT_ALIGNMENT_CENTER
}
super.addView(child, params)
}
}
possible "side effects" - this will apply to "subtitle" too
How to center body on a page?
Also apply text-align: center; on the html element like so:
html {
text-align: center;
}
A better approach though is to have an inner container div, which will be centralized, and not the body.
How to make a <div> or <a href="#"> to align center
In your html file:
<a href="contact.html" class="button large hpbottom">Get Started</a>
In your css file:
.hpbottom{
text-align: center;
}
CSS: Center block, but align contents to the left
<div>
<div style="text-align: left; width: 400px; border: 1px solid black; margin: 0 auto;">
<pre>
Hello
Testing
Beep
</pre>
</div>
</div>
How do I center a window onscreen in C#?
using System;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Windows.Forms;
namespace centrewindow
{
public partial class Form1 : Form
{
public struct RECT
{
public int Left; // x position of upper-left corner
public int Top; // y position of upper-left corner
public int Right; // x position of lower-right corner
public int Bottom; // y position of lower-right corner
}
[DllImport("user32.dll")]
public static extern IntPtr SetWindowPos(IntPtr hWnd, int hWndInsertAfter, int x, int Y, int cx, int cy, int wFlags);
[DllImport("user32.dll")]
public static extern bool GetWindowRect(HandleRef hwnd, out RECT lpRect);
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
CentreWindow(Handle, GetMonitorDimensions());
}
private void CentreWindow(IntPtr handle, Size monitorDimensions)
{
RECT rect;
GetWindowRect(new HandleRef(this, handle), out rect);
var x1Pos = monitorDimensions.Width/2 - (rect.Right - rect.Left)/2;
var x2Pos = rect.Right - rect.Left;
var y1Pos = monitorDimensions.Height/2 - (rect.Bottom - rect.Top)/2;
var y2Pos = rect.Bottom - rect.Top;
SetWindowPos(handle, 0, x1Pos, y1Pos, x2Pos, y2Pos, 0);
}
private Size GetMonitorDimensions()
{
return SystemInformation.PrimaryMonitorSize;
}
}
}
Centers any window you can get the handle of
Bootstrap 3 modal vertical position center
All what I did in my case is to set the Top in my css knowing the height of the modal
<div id="myModal" class="modal fade"> ... </div>
in my css i set
#myModal{
height: 400px;
top: calc(50% - 200px) !important;
}
Two Divs on the same row and center align both of them
I would vote against display: inline-block since its not supported across browsers, IE < 8 specifically.
.wrapper {
width:500px; /* Adjust to a total width of both .left and .right */
margin: 0 auto;
}
.left {
float: left;
width: 49%; /* Not 50% because of 1px border. */
border: 1px solid #000;
}
.right {
float: right;
width: 49%; /* Not 50% because of 1px border. */
border: 1px solid #F00;
}
<div class="wrapper">
<div class="left">Div 1</div>
<div class="right">Div 2</div>
</div>
EDIT: If no spacing between the cells is desired just change both .left and .right to use float: left;
How to center absolute div horizontally using CSS?
Although above answers are correct but to make it simple for newbies, all you need to do is set margin, left and right. following code will do it provided that width is set and position is absolute:
margin: 0 auto;
left: 0;
right: 0;
Demo:
.centeredBox {_x000D_
margin: 0 auto;_x000D_
left: 0;_x000D_
right: 0;_x000D_
_x000D_
_x000D_
/** Position should be absolute */_x000D_
position: absolute;_x000D_
/** And box must have a width, any width */_x000D_
width: 40%;_x000D_
background: #faebd7;_x000D_
_x000D_
}<div class="centeredBox">Centered Box</div>ORA-03113: end-of-file on communication channel after long inactivity in ASP.Net app
You could try this registry hack:
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters]
"DeadGWDetectDefault"=dword:00000001
"KeepAliveTime"=dword:00120000
If it works, just keep increasing the KeepAliveTime. It is currently set for 2 minutes.
apt-get for Cygwin?
You can do this using Cygwin’s setup.exe from Windows command line. Example:
cd C:\cygwin64
setup-x86_64 -q -P wget,tar,gawk,bzip2,subversion,vim
For a more convenient installer, you may want to use the apt-cyg package manager. Its syntax is similar to apt-get, which is a plus. For this, follow the above steps and then use Cygwin Bash for the following steps:
wget rawgit.com/transcode-open/apt-cyg/master/apt-cyg
install apt-cyg /bin
Now that apt-cyg is installed. Here are a few examples of installing some
packages:
apt-cyg install nano
apt-cyg install git
apt-cyg install ca-certificates
Use of contains in Java ArrayList<String>
Your question is not very clear.
- What's your code exactly doing? Give more code.
- What's the error you're getting?
You say you get a null-pointer. You cannot get a null pointer as a value returned by contains().
However you can get a NullPointerException if your list has not been initialized. By reading your question now, I'd say that what you show here is correct, but maybe you just didn't instantiate the list.
For this to work (to add a feed URL if it isn't already in the list):
if (!this.rssFeedURLs.contains(rssFeedURL)) {
this.rssFeedURLs.add(rssFeedUrl);
}
then this declaration would do:
private ArrayList<String> rssFeedURLs = new ArrayList<String>();
or initialize your list later on, but before trying to access its methods:
rssFeedUrls = new ArrayList<String>();
Finally... Do you really need a List? Maybe a Set would be better if you don't want duplicates. Use a LinkedHashSet if preserving the ordering matters.
Read whole ASCII file into C++ std::string
I could do it like this:
void readfile(const std::string &filepath,std::string &buffer){
std::ifstream fin(filepath.c_str());
getline(fin, buffer, char(-1));
fin.close();
}
If this is something to be frowned upon, please let me know why
Using stored procedure output parameters in C#
I slightly modified your stored procedure (to use SCOPE_IDENTITY) and it looks like this:
CREATE PROCEDURE usp_InsertContract
@ContractNumber varchar(7),
@NewId int OUTPUT
AS
BEGIN
INSERT INTO [dbo].[Contracts] (ContractNumber)
VALUES (@ContractNumber)
SELECT @NewId = SCOPE_IDENTITY()
END
I tried this and it works just fine (with that modified stored procedure):
// define connection and command, in using blocks to ensure disposal
using(SqlConnection conn = new SqlConnection(pvConnectionString ))
using(SqlCommand cmd = new SqlCommand("dbo.usp_InsertContract", conn))
{
cmd.CommandType = CommandType.StoredProcedure;
// set up the parameters
cmd.Parameters.Add("@ContractNumber", SqlDbType.VarChar, 7);
cmd.Parameters.Add("@NewId", SqlDbType.Int).Direction = ParameterDirection.Output;
// set parameter values
cmd.Parameters["@ContractNumber"].Value = contractNumber;
// open connection and execute stored procedure
conn.Open();
cmd.ExecuteNonQuery();
// read output value from @NewId
int contractID = Convert.ToInt32(cmd.Parameters["@NewId"].Value);
conn.Close();
}
Does this work in your environment, too? I can't say why your original code won't work - but when I do this here, VS2010 and SQL Server 2008 R2, it just works flawlessly....
If you don't get back a value - then I suspect your table Contracts might not really have a column with the IDENTITY property on it.
How to identify platform/compiler from preprocessor macros?
For Mac OS:
#ifdef __APPLE__
For MingW on Windows:
#ifdef __MINGW32__
For Linux:
#ifdef __linux__
For other Windows compilers, check this thread and this for several other compilers and architectures.
How to fix a header on scroll
Coops answer is a good, simple solution, however, once you apply the fixed class the page becomes that much shorter and content will "jump" up, and if page is of a length where the scroll distance is less than the height of the header element, it will appear to jump and not let you see the bottom of the page.
The answer I found was to add a spacer div above the element that will become fixed (nav element in my case), and set it to the same height as the nav element, and set it to display none.
When adding the .fixed class to the nav, show the .nav-spacer div, and when removing it, hide it. Since the height of the page changes instantly I have set the duration to 0.
HTML
<header>the element above the element that will become fixed</header>
<div class="nav-spacer"></div>
<nav></nav>
CSS
nav {
position: relative;
height: 100px;
}
.nav-spacer{
position: relative;
height: 100px;
display: none;
}
.fixed {
position: fixed;
top:0;
left:0;
width: 100%;
/* I like to add a shadow on to the fixed element */
-webkit-box-shadow: 0px 5px 10px 1px rgba(0,0,0,0.25);
-moz-box-shadow: 0px 5px 10px 1px rgba(0,0,0,0.25);
box-shadow: 0px 5px 10px 1px rgba(0,0,0,0.25);
}
JavaScript
var stickyOffset = $('nav').offset().top;
$(window).scroll(function(){
if ($(window).scrollTop() >= stickyOffset){
$('nav').addClass('fixed');
//this makes the page length equal to what it was before fixing nav
$('.nav-spacer').show(0);
}
else {
$('nav').removeClass('fixed');
$('.nav-spacer').hide(0);
}
});
Hiding axis text in matplotlib plots
When using the object oriented API, the Axes object has two useful methods for removing the axis text, set_xticklabels() and set_xticks().
Say you create a plot using
fig, ax = plt.subplots(1)
ax.plot(x, y)
If you simply want to remove the tick labels, you could use
ax.set_xticklabels([])
or to remove the ticks completely, you could use
ax.set_xticks([])
These methods are useful for specifying exactly where you want the ticks and how you want them labeled. Passing an empty list results in no ticks, or no labels, respectively.
Getting "java.nio.file.AccessDeniedException" when trying to write to a folder
Not the answer for this question
I got this exception when trying to delete a folder where i deleted the file inside.
Example:
createFolder("folder");
createFile("folder/file");
deleteFile("folder/file");
deleteFolder("folder"); // error here
While deleteFile("folder/file"); returned that it was deleted, the folder will only be considered empty after the program restart.
On some operating systems it may not be possible to remove a file when it is open and in use by this Java virtual machine or other programs.
https://docs.oracle.com/javase/8/docs/api/java/nio/file/Files.html#delete-java.nio.file.Path-
Java character array initializer
char array[] = new String("Hi there").toCharArray();
for(char c : array)
System.out.print(c + " ");
How to add image background to btn-default twitter-bootstrap button?
<!-- Latest compiled and minified CSS -->_x000D_
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css">_x000D_
_x000D_
<!-- Optional theme -->_x000D_
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap-theme.min.css">_x000D_
_x000D_
<!-- Latest compiled and minified JavaScript -->_x000D_
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/js/bootstrap.min.js"></script>_x000D_
_x000D_
_x000D_
<style type="text/css">_x000D_
.sign-in-facebook_x000D_
{_x000D_
background-image: url('http://i.stack.imgur.com/e2S63.png');_x000D_
background-position: -9px -7px;_x000D_
background-repeat: no-repeat;_x000D_
background-size: 39px 43px;_x000D_
padding-left: 41px;_x000D_
color: #000;_x000D_
}_x000D_
.sign-in-facebook:hover_x000D_
{_x000D_
background-image: url('http://i.stack.imgur.com/e2S63.png');_x000D_
background-position: -9px -7px;_x000D_
background-repeat: no-repeat;_x000D_
background-size: 39px 43px;_x000D_
padding-left: 41px;_x000D_
color: #000;_x000D_
}_x000D_
</style>_x000D_
<p>My current button got white background<br/>_x000D_
<input type="button" value="Sign In with Facebook" class="sign-in-facebook btn btn-secondary" style="margin-top:2px; margin-bottom:2px;" >_x000D_
</p>_x000D_
<p>I need the current btn-default style like below<br/>_x000D_
<input type="button" class="btn btn-default" value="Sign In with Facebook" />_x000D_
</p>_x000D_
<strong>NOTE:</strong> facebook icon at left side of the button.OS X Terminal Colors
Check what $TERM gives: mine is xterm-color and ls -alG then does colorised output.
How to convert a byte array to a hex string in Java?
How about this?
String byteToHex(final byte[] hash)
{
Formatter formatter = new Formatter();
for (byte b : hash)
{
formatter.format("%02x", b);
}
String result = formatter.toString();
formatter.close();
return result;
}
What does the ^ (XOR) operator do?
XOR is a binary operation, it stands for "exclusive or", that is to say the resulting bit evaluates to one if only exactly one of the bits is set.
This is its function table:
a | b | a ^ b
--|---|------
0 | 0 | 0
0 | 1 | 1
1 | 0 | 1
1 | 1 | 0
This operation is performed between every two corresponding bits of a number.
Example: 7 ^ 10
In binary: 0111 ^ 1010
0111
^ 1010
======
1101 = 13
Properties: The operation is commutative, associative and self-inverse.
It is also the same as addition modulo 2.
How to make asynchronous HTTP requests in PHP
/**
* Asynchronously execute/include a PHP file. Does not record the output of the file anywhere.
*
* @param string $filename file to execute, relative to calling script
* @param string $options (optional) arguments to pass to file via the command line
*/
function asyncInclude($filename, $options = '') {
exec("/path/to/php -f {$filename} {$options} >> /dev/null &");
}
PySpark: multiple conditions in when clause
You get SyntaxError error exception because Python has no && operator. It has and and & where the latter one is the correct choice to create boolean expressions on Column (| for a logical disjunction and ~ for logical negation).
Condition you created is also invalid because it doesn't consider operator precedence. & in Python has a higher precedence than == so expression has to be parenthesized.
(col("Age") == "") & (col("Survived") == "0")
## Column<b'((Age = ) AND (Survived = 0))'>
On a side note when function is equivalent to case expression not WHEN clause. Still the same rules apply. Conjunction:
df.where((col("foo") > 0) & (col("bar") < 0))
Disjunction:
df.where((col("foo") > 0) | (col("bar") < 0))
You can of course define conditions separately to avoid brackets:
cond1 = col("Age") == ""
cond2 = col("Survived") == "0"
cond1 & cond2
Lumen: get URL parameter in a Blade view
As per official 5.8 docs:
The request() function returns the current request instance or obtains an input item:
$request = request();
$value = request('key', $default);
How do you use script variables in psql?
One final word on PSQL variables:
They don't expand if you enclose them in single quotes in the SQL statement. Thus this doesn't work:
SELECT * FROM foo WHERE bar = ':myvariable'To expand to a string literal in a SQL statement, you have to include the quotes in the variable set. However, the variable value already has to be enclosed in quotes, which means that you need a second set of quotes, and the inner set has to be escaped. Thus you need:
\set myvariable '\'somestring\'' SELECT * FROM foo WHERE bar = :myvariableEDIT: starting with PostgreSQL 9.1, you may write instead:
\set myvariable somestring SELECT * FROM foo WHERE bar = :'myvariable'
How can I echo the whole content of a .html file in PHP?
Just use:
<?php
include("/path/to/file.html");
?>
That will echo it as well. This also has the benefit of executing any PHP in the file.
If you need to do anything with the contents, use file_get_contents(),
For example,
<?php
$pagecontents = file_get_contents("/path/to/file.html");
echo str_replace("Banana", "Pineapple", $pagecontents);
?>
This doesn't execute code in that file, so be careful if you expect that to work.
I usually use:
include($_SERVER['DOCUMENT_ROOT']."/path/to/file/as/in/url.html");
as then I can move files without breaking the includes.
How to make a view with rounded corners?
try this property with your linear layout it will help
tools:context=".youractivity"
Get commit list between tags in git
git log takes a range of commits as an argument:
git log --pretty=[your_choice] tag1..tag2
See the man page for git rev-parse for more info.
How do I find the absolute position of an element using jQuery?
Note that $(element).offset() tells you the position of an element relative to the document. This works great in most circumstances, but in the case of position:fixed you can get unexpected results.
If your document is longer than the viewport and you have scrolled vertically toward the bottom of the document, then your position:fixed element's offset() value will be greater than the expected value by the amount you have scrolled.
If you are looking for a value relative to the viewport (window), rather than the document on a position:fixed element, you can subtract the document's scrollTop() value from the fixed element's offset().top value. Example: $("#el").offset().top - $(document).scrollTop()
If the position:fixed element's offset parent is the document, you want to read parseInt($.css('top')) instead.
How to export a Vagrant virtual machine to transfer it
My hard drive in my Mac was making beeping noises in the middle of a project so I decided to install a SSD. I needed to move my project from one disk to another. A few things to consider:
- I'm vagrant w/ virtualbox on a Mac
- I'm using git
This is what worked for me:
1.) Copy your ~/.vagrant.d directory to your new machine.
2.) Copy your ~/VirtualBox\ VMs directory to your new machine.
3.) In VirtualBox add the machines one by one using **Machine** >> **Add**
4.) Run `vagrant box list` to see if vagrant acknowledges your machines.
5.) `git clone my_project`
6.) `vagrant up`
I had a few problems with VB Guest additions.
I fixed them with this solution.
Pausing a batch file for amount of time
ping -n 11 -w 1000 127.0.0.1 > nul
Update
Beginner's mistake. Ping doesn't wait 1000 ms before or after an request, but inbetween requests. So to wait 10 seconds, you'll have to do 11 pings to have 10 'gaps' of a second inbetween.
Deep copy in ES6 using the spread syntax
Here's my deep copy algorithm.
const DeepClone = (obj) => {
if(obj===null||typeof(obj)!=='object')return null;
let newObj = { ...obj };
for (let prop in obj) {
if (
typeof obj[prop] === "object" ||
typeof obj[prop] === "function"
) {
newObj[prop] = DeepClone(obj[prop]);
}
}
return newObj;
};
How to create a responsive image that also scales up in Bootstrap 3
Not sure if it helps you still... but I had to do a small trick to make the image bigger but keeping it responsive
@media screen and (max-width: 368px) {
img.smallResolution{
min-height: 150px;
}
}
Hope it helps P.S. The max width can be anything you like
What is JavaScript's highest integer value that a number can go to without losing precision?
I write it like this:
var max_int = 0x20000000000000;
var min_int = -0x20000000000000;
(max_int + 1) === 0x20000000000000; //true
(max_int - 1) < 0x20000000000000; //true
Same for int32
var max_int32 = 0x80000000;
var min_int32 = -0x80000000;
Why I am getting Cannot pass parameter 2 by reference error when I am using bindParam with a constant value?
Based on the other answers but with a little more clarity on how to actually use this solution.
If for example you have an empty string for a time value but you want to save it as a null:
if($endtime == ""){
$db->bind(":endtime",$endtime=NULL,PDO::PARAM_STR);
}else{
$db->bind("endtime",$endtime);
}
Notice that for time values you would use PARAM_STR, as times are stored as strings.
Equivalent to 'app.config' for a library (DLL)
If you add Settings to a Class Library project in Visual Studio (Project Properties, Settings), it will add an app.config file to your project with the relevant userSettings/applicatioNSettings sections, and the default values for these settings from your Settings.settings file.
However this configuration file will not be used at runtime - instead the class library uses the configuration file of its hosting application.
I believe the main reason for generating this file is so that you can copy/paste the settings into the host application's configuration file.
Twig: in_array or similar possible within if statement?
It should help you.
{% for user in users if user.active and user.id not 1 %}
{{ user.name }}
{% endfor %}
More info: http://twig.sensiolabs.org/doc/tags/for.html
How to check if all of the following items are in a list?
An example of how to do this using a lambda expression would be:
issublist = lambda x, y: 0 in [_ in x for _ in y]
How do I format a String in an email so Outlook will print the line breaks?
I also had this issue with plain/text mail type.Form Feed \f worked for me.
Select Rows with id having even number
SELECT * FROM ( SELECT *, Row_Number()
OVER(ORDER BY country_gid) AS sdfg FROM eka_mst_tcountry ) t
WHERE t.country_gid % 2 = 0
Get first date of current month in java
In Java 8 you can use:
LocalDate date = LocalDate.now(); //2020-01-12
date.withDayOfMonth(1); //2020-01-01
Please add a @Pipe/@Directive/@Component annotation. Error
I faced the same error when I used another class instead of component down the component decorator.
Component class must come just after the component decorator
@Component({
selector: 'app-smsgtrecon',
templateUrl: './smsgtrecon.component.html',
styleUrls: ['./smsgtrecon.component.css'],
providers: [ChecklistDatabase]
})
// THIS CAUSE ISSUE MOVE THIS UP TO COMPONENT DECORATOR
/**
* Node for to-do item
*/
export class TodoItemNode {
children: TodoItemNode[];
item: string;
}
export class SmsgtreconComponent implements OnInit {
After moving TodoItemNode to the top of component decorator it worked
Solution
// THIS CAUSE ISSUE MOVE THIS UP TO COMPONENT DECORATOR
/**
* Node for to-do item
*/
export class TodoItemNode {
children: TodoItemNode[];
item: string;
}
@Component({
selector: 'app-smsgtrecon',
templateUrl: './smsgtrecon.component.html',
styleUrls: ['./smsgtrecon.component.css'],
providers: [ChecklistDatabase]
})
export class SmsgtreconComponent implements OnInit {
Connect Android Studio with SVN
In Android Studio we can get the repositories of svn using the VCS->Subversion and the extract the repository and work on the code
Open a local HTML file using window.open in Chrome
This worked for me fine:
File 1:
<html>
<head></head>
<body>
<a href="#" onclick="window.open('file:///D:/Examples/file2.html'); return false">CLICK ME</a>
</body>
<footer></footer>
</html>
File 2:
<html>
...
</html>
This method works regardless of whether or not the 2 files are in the same directory, BUT both files must be local.
For obvious security reasons, if File 1 is located on a remote server you absolutely cannot open a file on some client's host computer and trying to do so will open a blank target.
Replacing from match to end-of-line
awk
awk '{gsub(/two.*/,"")}1' file
Ruby
ruby -ne 'print $_.gsub(/two.*/,"")' file
Webfont Smoothing and Antialiasing in Firefox and Opera
... in the body tag and these from the content and the typeface looks better in general...
body, html {
width: 100%;
height: 100%;
margin: 0;
padding: 0;
text-rendering: optimizeLegibility;
text-rendering: geometricPrecision;
font-smooth: always;
font-smoothing: antialiased;
-moz-font-smoothing: antialiased;
-webkit-font-smoothing: antialiased;
-webkit-font-smoothing: subpixel-antialiased;
}
#content {
-webkit-font-smoothing: antialiased;
-moz-osx-font-smoothing: grayscale;
}
SASS - use variables across multiple files
You can do it like this:
I have a folder named utilities and inside that I have a file named _variables.scss
in that file i declare variables like so:
$black: #000;
$white: #fff;
then I have the style.scss file in which i import all of my other scss files like this:
// Utilities
@import "utilities/variables";
// Base Rules
@import "base/normalize";
@import "base/global";
then, within any of the files I have imported, I should be able to access the variables I have declared.
Just make sure you import the variable file before any of the others you would like to use it in.
Delete default value of an input text on click
Just use a placeholder tag in your input instead of value
Passing parameters to a JDBC PreparedStatement
Do something like this, which also prevents SQL injection attacks
statement = con.prepareStatement("SELECT * from employee WHERE userID = ?");
statement.setString(1, userID);
ResultSet rs = statement.executeQuery();
Gradle store on local file system
On Mac, Linux and Windows i.e. on all 3 of the major platforms, Gradle stores dependencies at:
~/.gradle/caches/modules-2/files-2.1
Sort a list of Class Instances Python
In addition to the solution you accepted, you could also implement the special __lt__() ("less than") method on the class. The sort() method (and the sorted() function) will then be able to compare the objects, and thereby sort them. This works best when you will only ever sort them on this attribute, however.
class Foo(object):
def __init__(self, score):
self.score = score
def __lt__(self, other):
return self.score < other.score
l = [Foo(3), Foo(1), Foo(2)]
l.sort()
Call a method of a controller from another controller using 'scope' in AngularJS
The best approach for you to communicate between the two controllers is to use events.
In this check out $on, $broadcast and $emit.
In general use case the usage of angular.element(catapp).scope() was designed for use outside the angular controllers, like within jquery events.
Ideally in your usage you would write an event in controller 1 as:
$scope.$on("myEvent", function (event, args) {
$scope.rest_id = args.username;
$scope.getMainCategories();
});
And in the second controller you'd just do
$scope.initRestId = function(){
$scope.$broadcast("myEvent", {username: $scope.user.username });
};
Edit: Realised it was communication between two modules
Can you try including the firstApp module as a dependency to the secondApp where you declare the angular.module. That way you can communicate to the other app.
python catch exception and continue try block
special_func to avoid try-except repetition:
def special_func(test_case_dict):
final_dict = {}
exception_dict = {}
def try_except_avoider(test_case_dict):
try:
for k,v in test_case_dict.items():
final_dict[k]=eval(v) #If no exception evaluate the function and add it to final_dict
except Exception as e:
exception_dict[k]=e #extract exception
test_case_dict.pop(k)
try_except_avoider(test_case_dict) #recursive function to handle remaining functions
finally: #cleanup
final_dict.update(exception_dict)
return final_dict #combine exception dict and final dict
return try_except_avoider(test_case_dict)
Run code:
def add(a,b):
return (a+b)
def sub(a,b):
return (a-b)
def mul(a,b):
return (a*b)
case = {"AddFunc":"add(8,8)","SubFunc":"sub(p,5)","MulFunc":"mul(9,6)"}
solution = special_func(case)
Output looks like:
{'AddFunc': 16, 'MulFunc': 54, 'SubFunc': NameError("name 'p' is not defined")}
To convert to variables:
locals().update(solution)
Variables would look like:
AddFunc = 16, MulFunc = 54, SubFunc = NameError("name 'p' is not defined")
How do I trap ctrl-c (SIGINT) in a C# console app
I can carry out some cleanups before exiting. What is the best way of doing this Thats is the real goal: trap exit, to make your own stuff. And neigther answers above not makeing it right. Because, Ctrl+C is just one of many ways to exiting app.
What in dotnet c# is needed for it - so called cancellation token passed to Host.RunAsync(ct) and then, in exit signals traps, for Windows it would be
private static readonly CancellationTokenSource cts = new CancellationTokenSource();
public static int Main(string[] args)
{
// For gracefull shutdown, trap unload event
AppDomain.CurrentDomain.ProcessExit += (sender, e) =>
{
cts.Cancel();
exitEvent.Wait();
};
Console.CancelKeyPress += (sender, e) =>
{
cts.Cancel();
exitEvent.Wait();
};
host.RunAsync(cts);
Console.WriteLine("Shutting down");
exitEvent.Set();
return 0;
}
...
How do I ALTER a PostgreSQL table and make a column unique?
Or, have the DB automatically assign a constraint name using:
ALTER TABLE foo ADD UNIQUE (thecolumn);
Find Facebook user (url to profile page) by known email address
Maybe things changed, but I recall rapleaf had a service where you enter an email address and you could receive a facebook id.
https://www.rapleaf.com/
If something was not in there, one could "sign up" with the email, and it should have a chance to get the data after a while.
I came across this when using a search tool called Maltego a few years back.
The app uses many types of "transforms", and a few where related to facebook and twitter etc..
..or find some new sqli's on fb and fb apps, hehe. :)
What does `void 0` mean?
What does void 0 mean?
void[MDN] is a prefix keyword that takes one argument and always returns undefined.
Examples
void 0
void (0)
void "hello"
void (new Date())
//all will return undefined
What's the point of that?
It seems pretty useless, doesn't it? If it always returns undefined, what's wrong with just using undefined itself?
In a perfect world we would be able to safely just use undefined: it's much simpler and easier to understand than void 0. But in case you've never noticed before, this isn't a perfect world, especially when it comes to Javascript.
The problem with using undefined was that undefined is not a reserved word (it is actually a property of the global object [wtfjs]). That is, undefined is a permissible variable name, so you could assign a new value to it at your own caprice.
alert(undefined); //alerts "undefined"
var undefined = "new value";
alert(undefined) // alerts "new value"
Note: This is no longer a problem in any environment that supports ECMAScript 5 or newer (i.e. in practice everywhere but IE 8), which defines the undefined property of the global object as read-only (so it is only possible to shadow the variable in your own local scope). However, this information is still useful for backwards-compatibility purposes.
alert(window.hasOwnProperty('undefined')); // alerts "true"
alert(window.undefined); // alerts "undefined"
alert(undefined === window.undefined); // alerts "true"
var undefined = "new value";
alert(undefined); // alerts "new value"
alert(undefined === window.undefined); // alerts "false"
void, on the other hand, cannot be overidden. void 0 will always return undefined. undefined, on the other hand, can be whatever Mr. Javascript decides he wants it to be.
Why void 0, specifically?
Why should we use void 0? What's so special about 0? Couldn't we just as easily use 1, or 42, or 1000000 or "Hello, world!"?
And the answer is, yes, we could, and it would work just as well. The only benefit of passing in 0 instead of some other argument is that 0 is short and idiomatic.
Why is this still relevant?
Although undefined can generally be trusted in modern JavaScript environments, there is one trivial advantage of void 0: it's shorter. The difference is not enough to worry about when writing code but it can add up enough over large code bases that most code minifiers replace undefined with void 0 to reduce the number of bytes sent to the browser.
How do I POST XML data to a webservice with Postman?
Send XML requests with the raw data type, then set the Content-Type to text/xml.
After creating a request, use the dropdown to change the request type to POST.
Open the Body tab and check the data type for raw.
Open the Content-Type selection box that appears to the right and select either XML (application/xml) or XML (text/xml)
Enter your raw XML data into the input field below
Click Send to submit your XML Request to the specified server.
How do you determine the ideal buffer size when using FileInputStream?
In BufferedInputStream‘s source you will find: private static int DEFAULT_BUFFER_SIZE = 8192;
So it's okey for you to use that default value.
But if you can figure out some more information you will get more valueable answers.
For example, your adsl maybe preffer a buffer of 1454 bytes, thats because TCP/IP's payload. For disks, you may use a value that match your disk's block size.
Add column with constant value to pandas dataframe
Super simple in-place assignment: df['new'] = 0
For in-place modification, perform direct assignment. This assignment is broadcasted by pandas for each row.
df = pd.DataFrame('x', index=range(4), columns=list('ABC'))
df
A B C
0 x x x
1 x x x
2 x x x
3 x x x
df['new'] = 'y'
# Same as,
# df.loc[:, 'new'] = 'y'
df
A B C new
0 x x x y
1 x x x y
2 x x x y
3 x x x y
Note for object columns
If you want to add an column of empty lists, here is my advice:
- Consider not doing this.
objectcolumns are bad news in terms of performance. Rethink how your data is structured. - Consider storing your data in a sparse data structure. More information: sparse data structures
If you must store a column of lists, ensure not to copy the same reference multiple times.
# Wrong df['new'] = [[]] * len(df) # Right df['new'] = [[] for _ in range(len(df))]
Generating a copy: df.assign(new=0)
If you need a copy instead, use DataFrame.assign:
df.assign(new='y')
A B C new
0 x x x y
1 x x x y
2 x x x y
3 x x x y
And, if you need to assign multiple such columns with the same value, this is as simple as,
c = ['new1', 'new2', ...]
df.assign(**dict.fromkeys(c, 'y'))
A B C new1 new2
0 x x x y y
1 x x x y y
2 x x x y y
3 x x x y y
Multiple column assignment
Finally, if you need to assign multiple columns with different values, you can use assign with a dictionary.
c = {'new1': 'w', 'new2': 'y', 'new3': 'z'}
df.assign(**c)
A B C new1 new2 new3
0 x x x w y z
1 x x x w y z
2 x x x w y z
3 x x x w y z
How to create a POJO?
POJO class acts as a bean which is used to set and get the value.
public class Data
{
private int id;
private String deptname;
private String date;
private String name;
private String mdate;
private String mname;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getDeptname() {
return deptname;
}
public void setDeptname(String deptname) {
this.deptname = deptname;
}
public String getDate() {
return date;
}
public void setDate(String date) {
this.date = date;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getMdate() {
return mdate;
}
public void setMdate(String mdate) {
this.mdate = mdate;
}
public String getMname() {
return mname;
}
public void setMname(String mname) {
this.mname = mname;
}
}
Set UITableView content inset permanently
This is how it can be fixed easily through Storyboard (iOS 11 and Xcode 9.1):
Select Table View > Size Inspector > Content Insets: Never
Fixed digits after decimal with f-strings
Adding to Rob?'s answer: in case you want to print rather large numbers, using thousand separators can be a great help (note the comma).
>>> f'{a*1000:,.2f}'
'10,123.40'
Calculate difference between two datetimes in MySQL
If your start and end datetimes are on different days use TIMEDIFF.
SELECT TIMEDIFF(datetime1,datetime2)
if datetime1 > datetime2 then
SELECT TIMEDIFF("2019-02-20 23:46:00","2019-02-19 23:45:00")
gives: 24:01:00
and datetime1 < datetime2
SELECT TIMEDIFF("2019-02-19 23:45:00","2019-02-20 23:46:00")
gives: -24:01:00
include external .js file in node.js app
To place an emphasis on what everyone else has been saying var foo in top level does not create a global variable. If you want a global variable then write global.foo. but we all know globals are evil.
If you are someone who uses globals like that in a node.js project I was on I would refactor them away for as there are just so few use cases for this (There are a few exceptions but this isn't one).
// Declare application
var app = require('express').createServer();
// Declare usefull stuff for DB purposes
var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var ObjectId = Schema.ObjectId;
require('./models/car.js').make(Schema, mongoose);
in car.js
function make(Schema, mongoose) {
// Define Car model
CarSchema = new Schema({
brand : String,
type : String
});
mongoose.model('Car', CarSchema);
}
module.exports.make = make;
CSS: Responsive way to center a fluid div (without px width) while limiting the maximum width?
I think you can use display: inline-block on the element you want to center and set text-align: center; on its parent. This definitely center the div on all screen sizes.
Here you can see a fiddle: http://jsfiddle.net/PwC4T/2/ I add the code here for completeness.
HTML
<div id="container">
<div id="main">
<div id="somebackground">
Hi
</div>
</div>
</div>
CSS
#container
{
text-align: center;
}
#main
{
display: inline-block;
}
#somebackground
{
text-align: left;
background-color: red;
}
For vertical centering, I "dropped" support for some older browsers in favour of display: table;, which absolutely reduce code, see this fiddle: http://jsfiddle.net/jFAjY/1/
Here is the code (again) for completeness:
HTML
<body>
<div id="table-container">
<div id="container">
<div id="main">
<div id="somebackground">
Hi
</div>
</div>
</div>
</div>
</body>
CSS
body, html
{
height: 100%;
}
#table-container
{
display: table;
text-align: center;
width: 100%;
height: 100%;
}
#container
{
display: table-cell;
vertical-align: middle;
}
#main
{
display: inline-block;
}
#somebackground
{
text-align: left;
background-color: red;
}
The advantage of this approach? You don't have to deal with any percantage, it also handles correctly the <video> tag (html5), which has two different sizes (one during load, one after load, you can't fetch the tag size 'till video is loaded).
The downside is that it drops support for some older browser (I think IE8 won't handle this correctly)
Error 'tunneling socket' while executing npm install
I know this is way too late but if someone has a similar issue in the future and you are sure you have no proxy set but you have an environment variable called http_proxy. Please delete it and try again. I had set a proxy for Fiddler.
How to get HttpClient to pass credentials along with the request?
Ok so I took Joshoun code and made it generic. I am not sure if I should implement singleton pattern on SynchronousPost class. Maybe someone more knowledgeble can help.
Implementation
//I assume you have your own concrete type. In my case I have am using code first with a class called FileCategoryFileCategory x = new FileCategory { CategoryName = "Some Bs"};
SynchronousPost<FileCategory>test= new SynchronousPost<FileCategory>();
test.PostEntity(x, "/api/ApiFileCategories");
Generic Class here. You can pass any type
public class SynchronousPost<T>where T :class
{
public SynchronousPost()
{
Client = new WebClient { UseDefaultCredentials = true };
}
public void PostEntity(T PostThis,string ApiControllerName)//The ApiController name should be "/api/MyName/"
{
//this just determines the root url.
Client.BaseAddress = string.Format(
(
System.Web.HttpContext.Current.Request.Url.Port != 80) ? "{0}://{1}:{2}" : "{0}://{1}",
System.Web.HttpContext.Current.Request.Url.Scheme,
System.Web.HttpContext.Current.Request.Url.Host,
System.Web.HttpContext.Current.Request.Url.Port
);
Client.Headers.Add(HttpRequestHeader.ContentType, "application/json;charset=utf-8");
Client.UploadData(
ApiControllerName, "Post",
Encoding.UTF8.GetBytes
(
JsonConvert.SerializeObject(PostThis)
)
);
}
private WebClient Client { get; set; }
}
My Api classs looks like this, if you are curious
public class ApiFileCategoriesController : ApiBaseController
{
public ApiFileCategoriesController(IMshIntranetUnitOfWork unitOfWork)
{
UnitOfWork = unitOfWork;
}
public IEnumerable<FileCategory> GetFiles()
{
return UnitOfWork.FileCategories.GetAll().OrderBy(x=>x.CategoryName);
}
public FileCategory GetFile(int id)
{
return UnitOfWork.FileCategories.GetById(id);
}
//Post api/ApileFileCategories
public HttpResponseMessage Post(FileCategory fileCategory)
{
UnitOfWork.FileCategories.Add(fileCategory);
UnitOfWork.Commit();
return new HttpResponseMessage();
}
}
I am using ninject, and repo pattern with unit of work. Anyways, the generic class above really helps.
Fatal error: "No Target Architecture" in Visual Studio
Use #include <windows.h> instead of #include <windef.h>.
From the windows.h wikipedia page:
There are a number of child header files that are automatically included with
windows.h. Many of these files cannot simply be included by themselves (they are not self-contained), because of dependencies.
windef.h is one of the files automatically included with windows.h.
Can't concatenate 2 arrays in PHP
$array = array('Item 1');
array_push($array,'Item 2');
or
$array[] = 'Item 2';
Find all files with name containing string
find $HOME -name "hello.c" -print
This will search the whole $HOME (i.e. /home/username/) system for any files named “hello.c” and display their pathnames:
/Users/user/Downloads/hello.c
/Users/user/hello.c
However, it will not match HELLO.C or HellO.C. To match is case insensitive pass the -iname option as follows:
find $HOME -iname "hello.c" -print
Sample outputs:
/Users/user/Downloads/hello.c
/Users/user/Downloads/Y/Hello.C
/Users/user/Downloads/Z/HELLO.c
/Users/user/hello.c
Pass the -type f option to only search for files:
find /dir/to/search -type f -iname "fooBar.conf.sample" -print
find $HOME -type f -iname "fooBar.conf.sample" -print
The -iname works either on GNU or BSD (including OS X) version find command. If your version of find command does not supports -iname, try the following syntax using grep command:
find $HOME | grep -i "hello.c"
find $HOME -name "*" -print | grep -i "hello.c"
OR try
find $HOME -name '[hH][eE][lL][lL][oO].[cC]' -print
Sample outputs:
/Users/user/Downloads/Z/HELLO.C
/Users/user/Downloads/Z/HEllO.c
/Users/user/Downloads/hello.c
/Users/user/hello.c
Find non-ASCII characters in varchar columns using SQL Server
This script searches for non-ascii characters in one column. It generates a string of all valid characters, here code point 32 to 127. Then it searches for rows that don't match the list:
declare @str varchar(128)
declare @i int
set @str = ''
set @i = 32
while @i <= 127
begin
set @str = @str + '|' + char(@i)
set @i = @i + 1
end
select col1
from YourTable
where col1 like '%[^' + @str + ']%' escape '|'
How do I `jsonify` a list in Flask?
Solved, no fuss. You can be lazy and use jsonify, all you need to do is pass in items=[your list].
Take a look here for the solution
How do I get the find command to print out the file size with the file name?
You need to use -exec or -printf. Printf works like this:
find . -name *.ear -printf "%p %k KB\n"
-exec is more powerful and lets you execute arbitrary commands - so you could use a version of 'ls' or 'wc' to print out the filename along with other information. 'man find' will show you the available arguments to printf, which can do a lot more than just filesize.
[edit] -printf is not in the official POSIX standard, so check if it is supported on your version. However, most modern systems will use GNU find or a similarly extended version, so there is a good chance it will be implemented.
Google Chrome: This setting is enforced by your administrator
Try to use this solution:
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Google\Chrome
Run regedit, Delete the key, then restart Chrome.
how to align text vertically center in android
Try to put android:gravity="center_vertical|right" inside parent LinearLayout else as you are inside RelativeLayout you can put android:layout_centerInParent="true" inside your scrollView.
What does appending "?v=1" to CSS and JavaScript URLs in link and script tags do?
This makes sure you are getting the latest version from of the css or js file from the server.
And later you can append "?v=2" if you have a newer version and "?v=3", "?v=4" and so on.
Note that you can use any querystring, 'v' is not a must for example:
"?blah=1" will work as well.
And
"?xyz=1002" will work.
And this is a common technique because browsers are now caching js and css files better and longer.
Subscript out of bounds - general definition and solution?
Only an addition to the above responses: A possibility in such cases is that you are calling an object, that for some reason is not available to your query. For example you may subset by row names or column names, and you will receive this error message when your requested row or column is not part of the data matrix or data frame anymore. Solution: As a short version of the responses above: you need to find the last working row name or column name, and the next called object should be the one that could not be found. If you run parallel codes like "foreach", then you need to convert your code to a for loop to be able to troubleshoot it.
Cannot connect to local SQL Server with Management Studio
Open Sql server 2014 Configuration Manager.
Click Sql server services and start the sql server service if it is stopped
Then click Check SQL server Network Configuration for TCP/IP Enabled
then restart the sql server management studio (SSMS) and connect your local database engine
Creating a simple configuration file and parser in C++
libconfig is very easy, and what's better, it uses a pseudo json notation for better readability.
Easy to install on Ubuntu: sudo apt-get install libconfig++8-dev
and link: -lconfig++
How to write both h1 and h2 in the same line?
In many cases,
display:inline;
is enough.
But in some cases, you have to add following:
clear:none;
Serializing/deserializing with memory stream
Use Method to Serialize and Deserialize Collection object from memory. This works on Collection Data Types. This Method will Serialize collection of any type to a byte stream. Create a Seperate Class SerilizeDeserialize and add following two methods:
public class SerilizeDeserialize
{
// Serialize collection of any type to a byte stream
public static byte[] Serialize<T>(T obj)
{
using (MemoryStream memStream = new MemoryStream())
{
BinaryFormatter binSerializer = new BinaryFormatter();
binSerializer.Serialize(memStream, obj);
return memStream.ToArray();
}
}
// DSerialize collection of any type to a byte stream
public static T Deserialize<T>(byte[] serializedObj)
{
T obj = default(T);
using (MemoryStream memStream = new MemoryStream(serializedObj))
{
BinaryFormatter binSerializer = new BinaryFormatter();
obj = (T)binSerializer.Deserialize(memStream);
}
return obj;
}
}
How To use these method in your Class:
ArrayList arrayListMem = new ArrayList() { "One", "Two", "Three", "Four", "Five", "Six", "Seven" };
Console.WriteLine("Serializing to Memory : arrayListMem");
byte[] stream = SerilizeDeserialize.Serialize(arrayListMem);
ArrayList arrayListMemDes = new ArrayList();
arrayListMemDes = SerilizeDeserialize.Deserialize<ArrayList>(stream);
Console.WriteLine("DSerializing From Memory : arrayListMemDes");
foreach (var item in arrayListMemDes)
{
Console.WriteLine(item);
}
Changing file permission in Python
No need to remember flags. Remember that you can always do:
subprocess.call(["chmod", "a-w", "file/path])
Not portable but easy to write and remember:
- u - user
- g - group
- o - other
- a - all
- + or - (add or remove permission)
- r - read
- w - write
- x - execute
Refer man chmod for additional options and more detailed explanation.
$('body').on('click', '.anything', function(){})
You can try this:
You must follow the following format
$('element,id,class').on('click', function(){....});
*JQuery code*
$('body').addClass('.anything').on('click', function(){
//do some code here i.e
alert("ok");
});
How can I catch a ctrl-c event?
signal isn't the most reliable way as it differs in implementations. I would recommend using sigaction. Tom's code would now look like this :
#include <signal.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
void my_handler(int s){
printf("Caught signal %d\n",s);
exit(1);
}
int main(int argc,char** argv)
{
struct sigaction sigIntHandler;
sigIntHandler.sa_handler = my_handler;
sigemptyset(&sigIntHandler.sa_mask);
sigIntHandler.sa_flags = 0;
sigaction(SIGINT, &sigIntHandler, NULL);
pause();
return 0;
}
Python Script to convert Image into Byte array
This works for me
# Convert image to bytes
import PIL.Image as Image
pil_im = Image.fromarray(image)
b = io.BytesIO()
pil_im.save(b, 'jpeg')
im_bytes = b.getvalue()
return im_bytes
Root element is missing
Check the trees.config file which located in config folder... sometimes (I don't know why) this file became to be empty like someone delete the content inside... keep backup up of this file in your local pc then when this error appear - replace the server file with your local file. This is what i do when this error happened.
check the available space on the server. sometimes this is the problem.
Good luck.
How to provide a mysql database connection in single file in nodejs
I took a similar approach as Sean3z but instead I have the connection closed everytime i make a query.
His way works if it's only executed on the entry point of your app, but let's say you have controllers that you want to do a var db = require('./db'). You can't because otherwise everytime you access that controller you will be creating a new connection.
To avoid that, i think it's safer, in my opinion, to open and close the connection everytime.
here is a snippet of my code.
mysq_query.js
// Dependencies
var mysql = require('mysql'),
config = require("../config");
/*
* @sqlConnection
* Creates the connection, makes the query and close it to avoid concurrency conflicts.
*/
var sqlConnection = function sqlConnection(sql, values, next) {
// It means that the values hasnt been passed
if (arguments.length === 2) {
next = values;
values = null;
}
var connection = mysql.createConnection(config.db);
connection.connect(function(err) {
if (err !== null) {
console.log("[MYSQL] Error connecting to mysql:" + err+'\n');
}
});
connection.query(sql, values, function(err) {
connection.end(); // close the connection
if (err) {
throw err;
}
// Execute the callback
next.apply(this, arguments);
});
}
module.exports = sqlConnection;
Than you can use it anywhere just doing like
var mysql_query = require('path/to/your/mysql_query');
mysql_query('SELECT * from your_table where ?', {id: '1'}, function(err, rows) {
console.log(rows);
});
UPDATED: config.json looks like
{
"db": {
"user" : "USERNAME",
"password" : "PASSWORD",
"database" : "DATABASE_NAME",
"socketPath": "/tmp/mysql.sock"
}
}
Hope this helps.
Search for one value in any column of any table inside a database
I found a fairly robust solution at https://gallery.technet.microsoft.com/scriptcenter/c0c57332-8624-48c0-b4c3-5b31fe641c58 , which I thought was worth pointing out. It searches columns of these types: varchar, char, nvarchar, nchar, text. It works great and supports specific table-searching as well as multiple search-terms.
How to create JSON Object using String?
In contrast to what the accepted answer proposes, the documentation says that for JSONArray() you must use put(value) no add(value).
https://developer.android.com/reference/org/json/JSONArray.html#put(java.lang.Object)
(Android API 19-27. Kotlin 1.2.50)
Get dates from a week number in T-SQL
Another way to do it:
declare @week_number int;
declare @start_weekday int = 0 -- Monday
declare @end_weekday int = 6 -- next Sunday
select @week_number = datediff(week, 0, getdate())
select
dateadd(week, @week_number, @start_weekday) as WEEK_FIRST_DAY,
dateadd(week, @week_number, @end_weekday) as WEEK_LAST_DAY
Explanation:
- @week_number is computed based on the initial calendar date '1900-01-01'. Replace getdate() by whatever date you want.
- @start_weekday is 0 if Monday. If Sunday, then declare it as -1
- @end_weekday is 6 if next Sunday. If Saturday, then declare it as 5
- Then
dateaddfunction, will add the given number of weeks and the given number of days to the initial calendar date '1900-01-01'.
jQuery - Sticky header that shrinks when scrolling down
Here a CSS animation fork of jezzipin's Solution, to seperate code from styling.
JS:
$(window).on("scroll touchmove", function () {
$('#header_nav').toggleClass('tiny', $(document).scrollTop() > 0);
});
CSS:
.header {
width:100%;
height:100px;
background: #26b;
color: #fff;
position:fixed;
top:0;
left:0;
transition: height 500ms, background 500ms;
}
.header.tiny {
height:40px;
background: #aaa;
}
http://jsfiddle.net/sinky/S8Fnq/
On scroll/touchmove the css class "tiny" is set to "#header_nav" if "$(document).scrollTop()" is greater than 0.
CSS transition attribute animates the "height" and "background" attribute nicely.
Add a reference column migration in Rails 4
Create a migration file
rails generate migration add_references_to_uploads user:references
Default foreign key name
This would create a user_id column in uploads table as a foreign key
class AddReferencesToUploads < ActiveRecord::Migration[5.2]
def change
add_reference :uploads, :user, foreign_key: true
end
end
user model:
class User < ApplicationRecord
has_many :uploads
end
upload model:
class Upload < ApplicationRecord
belongs_to :user
end
Customize foreign key name:
add_reference :uploads, :author, references: :user, foreign_key: true
This would create an author_id column in the uploads tables as the foreign key.
user model:
class User < ApplicationRecord
has_many :uploads, foreign_key: 'author_id'
end
upload model:
class Upload < ApplicationRecord
belongs_to :user
end
How can I set the initial value of Select2 when using AJAX?
https://github.com/select2/select2/issues/4272
only this solved my problem.
even you set default value by option, you have to format the object, which has the text attribute and this is what you want to show in your option.
so, your format function have to use || to choose the attribute which is not empty.
.NET unique object identifier
You would have to assign such an identifier yourself, manually - either inside the instance, or externally.
For records related to a database, the primary key may be useful (but you can still get duplicates). Alternatively, either use a Guid, or keep your own counter, allocating using Interlocked.Increment (and make it large enough that it isn't likely to overflow).
How do I find all of the symlinks in a directory tree?
This will recursively traverse the /path/to/folder directory and list only the symbolic links:
ls -lR /path/to/folder | grep ^l
If your intention is to follow the symbolic links too, you should use your find command but you should include the -L option; in fact the find man page says:
-L Follow symbolic links. When find examines or prints information
about files, the information used shall be taken from the prop-
erties of the file to which the link points, not from the link
itself (unless it is a broken symbolic link or find is unable to
examine the file to which the link points). Use of this option
implies -noleaf. If you later use the -P option, -noleaf will
still be in effect. If -L is in effect and find discovers a
symbolic link to a subdirectory during its search, the subdirec-
tory pointed to by the symbolic link will be searched.
When the -L option is in effect, the -type predicate will always
match against the type of the file that a symbolic link points
to rather than the link itself (unless the symbolic link is bro-
ken). Using -L causes the -lname and -ilname predicates always
to return false.
Then try this:
find -L /var/www/ -type l
This will probably work: I found in the find man page this diamond: if you are using the -type option you have to change it to the -xtype option:
l symbolic link; this is never true if the -L option or the
-follow option is in effect, unless the symbolic link is
broken. If you want to search for symbolic links when -L
is in effect, use -xtype.
Then:
find -L /var/www/ -xtype l
Match everything except for specified strings
If you want to make sure that the string is neither red, green nor blue, caskey's answer is it. What is often wanted, however, is to make sure that the line does not contain red, green or blue anywhere in it. For that, anchor the regular expression with ^ and include .* in the negative lookahead:
^(?!.*(red|green|blue))
Also, suppose that you want lines containing the word "engine" but without any of those colors:
^(?!.*(red|green|blue)).*engine
You might think you can factor the .* to the head of the regular expression:
^.*(?!red|green|blue)engine # Does not work
but you cannot. You have to have both instances of .* for it to work.
Parsing a JSON array using Json.Net
Use Manatee.Json https://github.com/gregsdennis/Manatee.Json/wiki/Usage
And you can convert the entire object to a string, filename.json is expected to be located in documents folder.
var text = File.ReadAllText("filename.json");
var json = JsonValue.Parse(text);
while (JsonValue.Null != null)
{
Console.WriteLine(json.ToString());
}
Console.ReadLine();
Set color of text in a Textbox/Label to Red and make it bold in asp.net C#
Another way of doing it. This approach can be useful for changing the text to 2 different colors, just by adding 2 spans.
Label1.Text = "String with original color" + "<b><span style=""color:red;"">" + "Your String Here" + "</span></b>";
what does "dead beef" mean?
Since IPv6-Adresses are written in Hex-notation you can use "Hexspeak" (numbers 0-9 and letters a-f) in Adresses.
There are a number of words you can use as valid adresses to better momorize them.
If you ping6 www.facebook.com -n you will get something like "2a03:2880:f01c:601:face:b00c:0:1".
Here are some examples:
- :affe:: (Affe - German for Monkey - seen at a vlan for management board)
- :1bad:babe:: (one bad babe - seen at a smtp-honeypot)
- :badc:ab1e:: (bad cable - seen as subnet for a unsecure vlan)
- :da7a:: (Data - seen for fileservers)
- :d1a1:: (Dial - seen for VPN Dial-In)
This app won't run unless you update Google Play Services (via Bazaar)
After updating to ADT 22.0.1, due to Android private libraries, the Google Maps service was giving some error and the app crashed. So I found the solution finally and it worked for me.
Just install the Google Play service library and then go to google-play-service/libproject/google-play-services_lib from https://www.dropbox.com/sh/2ok76ep7lmav0qf/9XVlv61D2b. Import that into your workspace. Clean your project where you want to use gogole-play-services-lib and then build it again and go to the Project -> Properties -> Java BuildPath -> select "Android Private Libraries, Android Dependencies, google-play-service"
In Properties itself, go to Android and then choose any of the versions and then choose add and select google-play-service-lib and then press apply and finally OK.
At last, go to the Project -> Android Tools -> Android Support Libraries. Accept the license and after installing then run your project.
It will work fine.
correct way of comparing string jquery operator =
No. = sets somevar to have that value. use === to compare value and type which returns a boolean that you need.
Never use or suggest == instead of ===. its a recipe for disaster. e.g 0 == "" is true but "" == '0' is false and many more.
More information also in this great answer
Firebase onMessageReceived not called when app in background
you can try this in your main Activity , when in the background
if (getIntent().getExtras() != null) {
for (String key : getIntent().getExtras().keySet()) {
Object value = getIntent().getExtras().get(key);
Log.d(TAG, "Key: " + key + " Value: " + value);
}
}
Check the following project as reference
How to `wget` a list of URLs in a text file?
Quick man wget gives me the following:
[..]
-i file
--input-file=file
Read URLs from a local or external file. If - is specified as file, URLs are read from the standard input. (Use ./- to read from a file literally named -.)
If this function is used, no URLs need be present on the command line. If there are URLs both on the command line and in an input file, those on the command lines will be the first ones to be retrieved. If --force-html is not specified, then file should consist of a series of URLs, one per line.
[..]
So: wget -i text_file.txt
How to set tbody height with overflow scroll
Based on this answer, here's a minimal solution if you're already using Bootstrap:
div.scrollable-table-wrapper {
height: 500px;
overflow: auto;
thead tr th {
position: sticky;
top: 0;
}
}
<div class="scrollable-table-wrapper">
<table class="table">
<thead>...</thead>
<tbody>...</tbody>
</table>
</div>
Tested on Bootstrap v3
python: SyntaxError: EOL while scanning string literal
I too had this problem, though there were answers here I want to an important point to this
after
/ there should not be empty spaces.Be Aware of it
background:none vs background:transparent what is the difference?
To complement the other answers: if you want to reset all background properties to their initial value (which includes background-color: transparent and background-image: none) without explicitly specifying any value such as transparent or none, you can do so by writing:
background: initial;
what's data-reactid attribute in html?
That's the HTML data attribute. See this for more detail: http://html5doctor.com/html5-custom-data-attributes/
Basically it's just a container of your custom data while still making the HTML valid.
It's data- plus some unique identifier.
round() for float in C++
It's usually implemented as floor(value + 0.5).
Edit: and it's probably not called round since there are at least three rounding algorithms I know of: round to zero, round to closest integer, and banker's rounding. You are asking for round to closest integer.
What's the valid way to include an image with no src?
I personally use an about:blank src and deal with the broken image icon by setting the opacity of the img element to 0.
"You may need an appropriate loader to handle this file type" with Webpack and Babel
If you are using Webpack > 3 then you only need to install babel-preset-env, since this preset accounts for es2015, es2016 and es2017.
var path = require('path');
let webpack = require("webpack");
module.exports = {
entry: {
app: './app/App.js',
vendor: ["react","react-dom"]
},
output: {
filename: 'bundle.js',
path: path.resolve(__dirname, '../public')
},
module: {
rules: [{
test: /\.jsx?$/,
exclude: /node_modules/,
use: {
loader: 'babel-loader?cacheDirectory=true',
}
}]
}
};
This picks up its configuration from my .babelrc file:
{
"presets": [
[
"env",
{
"targets": {
"browsers":["last 2 versions"],
"node":"current"
}
}
],["react"]
]
}
Adding days to a date in Java
Here is some simple code to give output as currentdate + D days = some 'x' date (future date):
DateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy");
Calendar c = Calendar.getInstance();
c.add(Calendar.DATE, 5);
System.out.println(dateFormat.format(c.getTime()));
tsc throws `TS2307: Cannot find module` for a local file
If use webstorm, press Ctrl+Alt+S and bring up the settings window. Languages&Frameworks>TypeScript, enable "use tsconfig.json" option.
Converting Milliseconds to Minutes and Seconds?
Here is the full program
import java.util.concurrent.TimeUnit;
public class Milliseconds {
public static void main(String[] args) {
long milliseconds = 1000000;
// long minutes = (milliseconds / 1000) / 60;
long minutes = TimeUnit.MILLISECONDS.toMinutes(milliseconds);
// long seconds = (milliseconds / 1000);
long seconds = TimeUnit.MILLISECONDS.toSeconds(milliseconds);
System.out.format("%d Milliseconds = %d minutes\n", milliseconds, minutes );
System.out.println("Or");
System.out.format("%d Milliseconds = %d seconds", milliseconds, seconds );
}
}
I found this program here "Link" there it is explained in detail.
Reading tab-delimited file with Pandas - works on Windows, but not on Mac
Another option would be to add engine='python' to the command pandas.read_csv(filename, sep='\t', engine='python')
Make an Android button change background on click through XML
Try:
public void onclick(View v){
ImageView activity= (ImageView) findViewById(R.id.imageview1);
button1.setImageResource(R.drawable.buttonpressed);}
Use images instead of radio buttons
Example:
Heads up! This solution is CSS-only.
I recommend you take advantage of CSS3 to do that, by hidding the by-default input radio button with CSS3 rules:
.options input{
margin:0;padding:0;
-webkit-appearance:none;
-moz-appearance:none;
appearance:none;
}
I just make an example a few days ago.
Create Carriage Return in PHP String?
There is also the PHP 5.0.2 PHP_EOL constant that is cross-platform !
perform an action on checkbox checked or unchecked event on html form
<form>
syn<input type="checkbox" name="checkfield" id="g01-01" />
</form>
js:
$('#g01-01').on('change',function(){
var _val = $(this).is(':checked') ? 'checked' : 'unchecked';
alert(_val);
});
How to move a file?
Based on the answer described here, using subprocess is another option.
Something like this:
subprocess.call("mv %s %s" % (source_files, destination_folder), shell=True)
I am curious to know the pro's and con's of this method compared to shutil. Since in my case I am already using subprocess for other reasons and it seems to work I am inclined to stick with it.
Is it system dependent maybe?
How to add rows dynamically into table layout
You might be better off using a ListView with a CursorAdapter (or SimpleCursorAdapter).
These are built to show rows from a sqlite database and allow refreshing with minimal programming on your part.
Edit - here is a tutorial involving SimpleCursorAdapter and ListView including sample code.
How does the data-toggle attribute work? (What's its API?)
The data-* attributes is used to store custom data private to the page or application
So Bootstrap uses these attributes for saving states of objects
CSS override rules and specificity
The specificity is calculated based on the amount of id, class and tag selectors in your rule. Id has the highest specificity, then class, then tag. Your first rule is now more specific than the second one, since they both have a class selector, but the first one also has two tag selectors.
To make the second one override the first one, you can make more specific by adding information of it's parents:
table.rule1 tr td.rule2 {
background-color: #ffff00;
}
Here is a nice article for more information on selector precedence.
How to sort multidimensional array by column?
below solution worked for me in case of required number is float. Solution:
table=sorted(table,key=lambda x: float(x[5]))
for row in table[:]:
Ntable.add_row(row)
'
Assets file project.assets.json not found. Run a NuGet package restore
To those with the same issue as me in Azure DevOps / VSTS environment encountering a similar message:
C:\Program Files\dotnet\sdk\2.2.104\Sdks\Microsoft.NET.Sdk\targets\Microsoft.PackageDependencyResolution.targets(208,5): Error NETSDK1004: Assets file '...\obj\project.assets.json' not found. Run a NuGet package restore to generate this file
Add /t:Restore to your MSBuild Arguments in Build Solution.
Converting between datetime, Timestamp and datetime64
import numpy as np
import pandas as pd
def np64toDate(np64):
return pd.to_datetime(str(np64)).replace(tzinfo=None).to_datetime()
use this function to get pythons native datetime object
Is it possible to add dynamically named properties to JavaScript object?
Just an addition to abeing's answer above. You can define a function to encapsulate the complexity of defineProperty as mentioned below.
var defineProp = function ( obj, key, value ){
var config = {
value: value,
writable: true,
enumerable: true,
configurable: true
};
Object.defineProperty( obj, key, config );
};
//Call the method to add properties to any object
defineProp( data, "PropertyA", 1 );
defineProp( data, "PropertyB", 2 );
defineProp( data, "PropertyC", 3 );
reference: http://addyosmani.com/resources/essentialjsdesignpatterns/book/#constructorpatternjavascript
How do I run a simple bit of code in a new thread?
If you are going to use the raw Thread object then you need to set IsBackground to true at a minimum and you should also set the Threading Apartment model (probably STA).
public static void DoWork()
{
// do some work
}
public static void StartWorker()
{
Thread worker = new Thread(DoWork);
worker.IsBackground = true;
worker.SetApartmentState(System.Threading.ApartmentState.STA);
worker.Start()
}
I would recommend the BackgroundWorker class if you need UI interaction.
How to manually set an authenticated user in Spring Security / SpringMVC
I couldn't find any other full solutions so I thought I would post mine. This may be a bit of a hack, but it resolved the issue to the above problem:
public void login(HttpServletRequest request, String userName, String password)
{
UsernamePasswordAuthenticationToken authRequest = new UsernamePasswordAuthenticationToken(userName, password);
// Authenticate the user
Authentication authentication = authenticationManager.authenticate(authRequest);
SecurityContext securityContext = SecurityContextHolder.getContext();
securityContext.setAuthentication(authentication);
// Create a new session and add the security context.
HttpSession session = request.getSession(true);
session.setAttribute("SPRING_SECURITY_CONTEXT", securityContext);
}
JavaFX Location is not set error message
I had the same problem, I changed the FXML name to the FXML file in the controller class and the problem was solved.
How to convert Set to Array?
Assuming you are just using Set temporarily to get unique values in an array and then converting back to an Array, try using this:
_.uniq([])
This relies on using underscore or lo-dash.
How can I remove a child node in HTML using JavaScript?
Modern Solution - child.remove()
For your use case:
document.getElementById("FirstDiv").remove()
This is recommended by W3C since late 2015, and is vanilla JS. All major browsers support it.
Supported Browsers - 96% May 2020
Short form for Java if statement
The ? : operator in Java
In Java you might write:
if (a > b) {
max = a;
}
else {
max = b;
}
Setting a single variable to one of two states based on a single condition is such a common use of if-else that a shortcut has been devised for it, the conditional operator, ?:. Using the conditional operator you can rewrite the above example in a single line like this:
max = (a > b) ? a : b;
(a > b) ? a : b; is an expression which returns one of two values, a or b. The condition, (a > b), is tested. If it is true the first value, a, is returned. If it is false, the second value, b, is returned. Whichever value is returned is dependent on the conditional test, a > b. The condition can be any expression which returns a boolean value.
Using "If cell contains #N/A" as a formula condition.
"N/A" is not a string it is an error, try this:
=if(ISNA(A1),C1)
you have to place this fomula in cell B1 so it will get the value of your formula
What is the difference between const int*, const int * const, and int const *?
const int*- pointer to constantintobject.
You can change the value of the pointer; you can not change the value of the int object, the pointer points to.
const int * const- constant pointer to constantintobject.
You can not change the value of the pointer nor the value of the int object the pointer points to.
int const *- pointer to constantintobject.
This statement is equivalent to 1. const int* - You can change the value of the pointer but you can not change the value of the int object, the pointer points to.
Actually, there is a 4th option:
int * const- constant pointer tointobject.
You can change the value of the object the pointer points to but you can not change the value of the pointer itself. The pointer will always point to the same int object but this value of this int object can be changed.
If you want to determine a certain type of C or C++ construct you can use the Clockwise/Spiral Rule made by David Anderson; but not to confuse with Anderson`s Rule made by Ross J. Anderson, which is something quite distinct.
How to replace all strings to numbers contained in each string in Notepad++?
Find: value="([\d]+|[\d])"
Replace: \1
It will really return you
4
403
200
201
116
15
js:
a='value="4"\nvalue="403"\nvalue="200"\nvalue="201"\nvalue="116"\nvalue="15"';
a = a.replace(/value="([\d]+|[\d])"/g, '$1');
console.log(a);
Initialize Array of Objects using NSArray
This might not really answer the question, but just in case someone just need to quickly send a string value to a function that require a NSArray parameter.
NSArray *data = @[@"The String Value"];
if you need to send more than just 1 string value, you could also use
NSArray *data = @[@"The String Value", @"Second String", @"Third etc"];
then you can send it to the function like below
theFunction(data);
Password encryption at client side
I've listed a complete JavaScript for creating an MD5 at the bottom but it's really pointless without a secure connection for several reasons.
If you MD5 the password and store that MD5 in your database then the MD5 is the password. People can tell exactly what's in your database. You've essentially just made the password a longer string but it still isn't secure if that's what you're storing in your database.
If you say, "Well I'll MD5 the MD5" you're missing the point. By looking at the network traffic, or looking in your database, I can spoof your website and send it the MD5. Granted this is a lot harder than just reusing a plain text password but it's still a security hole.
Most of all though you can't salt the hash client side without sending the salt over the 'net unencrypted therefore making the salting pointless. Without a salt or with a known salt I can brute force attack the hash and figure out what the password is.
If you are going to do this kind of thing with unencrypted transmissions you need to use a public key/private key encryption technique. The client encrypts using your public key then you decrypt on your end with your private key then you MD5 the password (using a user unique salt) and store it in your database. Here's a JavaScript GPL public/private key library.
Anyway, here is the JavaScript code to create an MD5 client side (not my code):
/**
*
* MD5 (Message-Digest Algorithm)
* http://www.webtoolkit.info/
*
**/
var MD5 = function (string) {
function RotateLeft(lValue, iShiftBits) {
return (lValue<<iShiftBits) | (lValue>>>(32-iShiftBits));
}
function AddUnsigned(lX,lY) {
var lX4,lY4,lX8,lY8,lResult;
lX8 = (lX & 0x80000000);
lY8 = (lY & 0x80000000);
lX4 = (lX & 0x40000000);
lY4 = (lY & 0x40000000);
lResult = (lX & 0x3FFFFFFF)+(lY & 0x3FFFFFFF);
if (lX4 & lY4) {
return (lResult ^ 0x80000000 ^ lX8 ^ lY8);
}
if (lX4 | lY4) {
if (lResult & 0x40000000) {
return (lResult ^ 0xC0000000 ^ lX8 ^ lY8);
} else {
return (lResult ^ 0x40000000 ^ lX8 ^ lY8);
}
} else {
return (lResult ^ lX8 ^ lY8);
}
}
function F(x,y,z) { return (x & y) | ((~x) & z); }
function G(x,y,z) { return (x & z) | (y & (~z)); }
function H(x,y,z) { return (x ^ y ^ z); }
function I(x,y,z) { return (y ^ (x | (~z))); }
function FF(a,b,c,d,x,s,ac) {
a = AddUnsigned(a, AddUnsigned(AddUnsigned(F(b, c, d), x), ac));
return AddUnsigned(RotateLeft(a, s), b);
};
function GG(a,b,c,d,x,s,ac) {
a = AddUnsigned(a, AddUnsigned(AddUnsigned(G(b, c, d), x), ac));
return AddUnsigned(RotateLeft(a, s), b);
};
function HH(a,b,c,d,x,s,ac) {
a = AddUnsigned(a, AddUnsigned(AddUnsigned(H(b, c, d), x), ac));
return AddUnsigned(RotateLeft(a, s), b);
};
function II(a,b,c,d,x,s,ac) {
a = AddUnsigned(a, AddUnsigned(AddUnsigned(I(b, c, d), x), ac));
return AddUnsigned(RotateLeft(a, s), b);
};
function ConvertToWordArray(string) {
var lWordCount;
var lMessageLength = string.length;
var lNumberOfWords_temp1=lMessageLength + 8;
var lNumberOfWords_temp2=(lNumberOfWords_temp1-(lNumberOfWords_temp1 % 64))/64;
var lNumberOfWords = (lNumberOfWords_temp2+1)*16;
var lWordArray=Array(lNumberOfWords-1);
var lBytePosition = 0;
var lByteCount = 0;
while ( lByteCount < lMessageLength ) {
lWordCount = (lByteCount-(lByteCount % 4))/4;
lBytePosition = (lByteCount % 4)*8;
lWordArray[lWordCount] = (lWordArray[lWordCount] | (string.charCodeAt(lByteCount)<<lBytePosition));
lByteCount++;
}
lWordCount = (lByteCount-(lByteCount % 4))/4;
lBytePosition = (lByteCount % 4)*8;
lWordArray[lWordCount] = lWordArray[lWordCount] | (0x80<<lBytePosition);
lWordArray[lNumberOfWords-2] = lMessageLength<<3;
lWordArray[lNumberOfWords-1] = lMessageLength>>>29;
return lWordArray;
};
function WordToHex(lValue) {
var WordToHexValue="",WordToHexValue_temp="",lByte,lCount;
for (lCount = 0;lCount<=3;lCount++) {
lByte = (lValue>>>(lCount*8)) & 255;
WordToHexValue_temp = "0" + lByte.toString(16);
WordToHexValue = WordToHexValue + WordToHexValue_temp.substr(WordToHexValue_temp.length-2,2);
}
return WordToHexValue;
};
function Utf8Encode(string) {
string = string.replace(/\r\n/g,"\n");
var utftext = "";
for (var n = 0; n < string.length; n++) {
var c = string.charCodeAt(n);
if (c < 128) {
utftext += String.fromCharCode(c);
}
else if((c > 127) && (c < 2048)) {
utftext += String.fromCharCode((c >> 6) | 192);
utftext += String.fromCharCode((c & 63) | 128);
}
else {
utftext += String.fromCharCode((c >> 12) | 224);
utftext += String.fromCharCode(((c >> 6) & 63) | 128);
utftext += String.fromCharCode((c & 63) | 128);
}
}
return utftext;
};
var x=Array();
var k,AA,BB,CC,DD,a,b,c,d;
var S11=7, S12=12, S13=17, S14=22;
var S21=5, S22=9 , S23=14, S24=20;
var S31=4, S32=11, S33=16, S34=23;
var S41=6, S42=10, S43=15, S44=21;
string = Utf8Encode(string);
x = ConvertToWordArray(string);
a = 0x67452301; b = 0xEFCDAB89; c = 0x98BADCFE; d = 0x10325476;
for (k=0;k<x.length;k+=16) {
AA=a; BB=b; CC=c; DD=d;
a=FF(a,b,c,d,x[k+0], S11,0xD76AA478);
d=FF(d,a,b,c,x[k+1], S12,0xE8C7B756);
c=FF(c,d,a,b,x[k+2], S13,0x242070DB);
b=FF(b,c,d,a,x[k+3], S14,0xC1BDCEEE);
a=FF(a,b,c,d,x[k+4], S11,0xF57C0FAF);
d=FF(d,a,b,c,x[k+5], S12,0x4787C62A);
c=FF(c,d,a,b,x[k+6], S13,0xA8304613);
b=FF(b,c,d,a,x[k+7], S14,0xFD469501);
a=FF(a,b,c,d,x[k+8], S11,0x698098D8);
d=FF(d,a,b,c,x[k+9], S12,0x8B44F7AF);
c=FF(c,d,a,b,x[k+10],S13,0xFFFF5BB1);
b=FF(b,c,d,a,x[k+11],S14,0x895CD7BE);
a=FF(a,b,c,d,x[k+12],S11,0x6B901122);
d=FF(d,a,b,c,x[k+13],S12,0xFD987193);
c=FF(c,d,a,b,x[k+14],S13,0xA679438E);
b=FF(b,c,d,a,x[k+15],S14,0x49B40821);
a=GG(a,b,c,d,x[k+1], S21,0xF61E2562);
d=GG(d,a,b,c,x[k+6], S22,0xC040B340);
c=GG(c,d,a,b,x[k+11],S23,0x265E5A51);
b=GG(b,c,d,a,x[k+0], S24,0xE9B6C7AA);
a=GG(a,b,c,d,x[k+5], S21,0xD62F105D);
d=GG(d,a,b,c,x[k+10],S22,0x2441453);
c=GG(c,d,a,b,x[k+15],S23,0xD8A1E681);
b=GG(b,c,d,a,x[k+4], S24,0xE7D3FBC8);
a=GG(a,b,c,d,x[k+9], S21,0x21E1CDE6);
d=GG(d,a,b,c,x[k+14],S22,0xC33707D6);
c=GG(c,d,a,b,x[k+3], S23,0xF4D50D87);
b=GG(b,c,d,a,x[k+8], S24,0x455A14ED);
a=GG(a,b,c,d,x[k+13],S21,0xA9E3E905);
d=GG(d,a,b,c,x[k+2], S22,0xFCEFA3F8);
c=GG(c,d,a,b,x[k+7], S23,0x676F02D9);
b=GG(b,c,d,a,x[k+12],S24,0x8D2A4C8A);
a=HH(a,b,c,d,x[k+5], S31,0xFFFA3942);
d=HH(d,a,b,c,x[k+8], S32,0x8771F681);
c=HH(c,d,a,b,x[k+11],S33,0x6D9D6122);
b=HH(b,c,d,a,x[k+14],S34,0xFDE5380C);
a=HH(a,b,c,d,x[k+1], S31,0xA4BEEA44);
d=HH(d,a,b,c,x[k+4], S32,0x4BDECFA9);
c=HH(c,d,a,b,x[k+7], S33,0xF6BB4B60);
b=HH(b,c,d,a,x[k+10],S34,0xBEBFBC70);
a=HH(a,b,c,d,x[k+13],S31,0x289B7EC6);
d=HH(d,a,b,c,x[k+0], S32,0xEAA127FA);
c=HH(c,d,a,b,x[k+3], S33,0xD4EF3085);
b=HH(b,c,d,a,x[k+6], S34,0x4881D05);
a=HH(a,b,c,d,x[k+9], S31,0xD9D4D039);
d=HH(d,a,b,c,x[k+12],S32,0xE6DB99E5);
c=HH(c,d,a,b,x[k+15],S33,0x1FA27CF8);
b=HH(b,c,d,a,x[k+2], S34,0xC4AC5665);
a=II(a,b,c,d,x[k+0], S41,0xF4292244);
d=II(d,a,b,c,x[k+7], S42,0x432AFF97);
c=II(c,d,a,b,x[k+14],S43,0xAB9423A7);
b=II(b,c,d,a,x[k+5], S44,0xFC93A039);
a=II(a,b,c,d,x[k+12],S41,0x655B59C3);
d=II(d,a,b,c,x[k+3], S42,0x8F0CCC92);
c=II(c,d,a,b,x[k+10],S43,0xFFEFF47D);
b=II(b,c,d,a,x[k+1], S44,0x85845DD1);
a=II(a,b,c,d,x[k+8], S41,0x6FA87E4F);
d=II(d,a,b,c,x[k+15],S42,0xFE2CE6E0);
c=II(c,d,a,b,x[k+6], S43,0xA3014314);
b=II(b,c,d,a,x[k+13],S44,0x4E0811A1);
a=II(a,b,c,d,x[k+4], S41,0xF7537E82);
d=II(d,a,b,c,x[k+11],S42,0xBD3AF235);
c=II(c,d,a,b,x[k+2], S43,0x2AD7D2BB);
b=II(b,c,d,a,x[k+9], S44,0xEB86D391);
a=AddUnsigned(a,AA);
b=AddUnsigned(b,BB);
c=AddUnsigned(c,CC);
d=AddUnsigned(d,DD);
}
var temp = WordToHex(a)+WordToHex(b)+WordToHex(c)+WordToHex(d);
return temp.toLowerCase();
}
Button Listener for button in fragment in android
Fragment Listener
If a fragment needs to communicate events to the activity, the fragment should define an interface as an inner type and require that the activity must implement this interface:
import android.support.v4.app.Fragment;
public class MyListFragment extends Fragment {
// ...
// Define the listener of the interface type
// listener is the activity itself
private OnItemSelectedListener listener;
// Define the events that the fragment will use to communicate
public interface OnItemSelectedListener {
public void onRssItemSelected(String link);
}
// Store the listener (activity) that will have events fired once the fragment is attached
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
if (activity instanceof OnItemSelectedListener) {
listener = (OnItemSelectedListener) activity;
} else {
throw new ClassCastException(activity.toString()
+ " must implement MyListFragment.OnItemSelectedListener");
}
}
// Now we can fire the event when the user selects something in the fragment
public void onSomeClick(View v) {
listener.onRssItemSelected("some link");
}
}
and then in the activity:
import android.support.v4.app.FragmentActivity;
public class RssfeedActivity extends FragmentActivity implements
MyListFragment.OnItemSelectedListener {
DetailFragment fragment;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_rssfeed);
fragment = (DetailFragment) getSupportFragmentManager()
.findFragmentById(R.id.detailFragment);
}
// Now we can define the action to take in the activity when the fragment event fires
@Override
public void onRssItemSelected(String link) {
if (fragment != null && fragment.isInLayout()) {
fragment.setText(link);
}
}
}
Mysql: Select all data between two dates
you must add 1 day to the end date, using: DATE_ADD('$end_date', INTERVAL 1 DAY)
What does [object Object] mean? (JavaScript)
If you are popping it in the DOM then try wrapping it in
<pre>
<code>{JSON.stringify(REPLACE_WITH_OBJECT, null, 4)}</code>
</pre>
makes a little easier to visually parse.
What is an API key?
What "exactly" an API key is used for depends very much on who issues it, and what services it's being used for. By and large, however, an API key is the name given to some form of secret token which is submitted alongside web service (or similar) requests in order to identify the origin of the request. The key may be included in some digest of the request content to further verify the origin and to prevent tampering with the values.
Typically, if you can identify the source of a request positively, it acts as a form of authentication, which can lead to access control. For example, you can restrict access to certain API actions based on who's performing the request. For companies which make money from selling such services, it's also a way of tracking who's using the thing for billing purposes. Further still, by blocking a key, you can partially prevent abuse in the case of too-high request volumes.
In general, if you have both a public and a private API key, then it suggests that the keys are themselves a traditional public/private key pair used in some form of asymmetric cryptography, or related, digital signing. These are more secure techniques for positively identifying the source of a request, and additionally, for protecting the request's content from snooping (in addition to tampering).
Use jQuery to hide a DIV when the user clicks outside of it
$('body').click(function(event) {
if (!$(event.target).is('p'))
{
$("#e2ma-menu").hide();
}
});
p is the element name. Where one can pass the id or class or element name also.
Is it possible to access to google translate api for free?
Yes, you can use GT for free. See the post with explanation. And look at repo on GitHub.
UPD 19.03.2019 Here is a version for browser on GitHub.
How does Java deal with multiple conditions inside a single IF statement
Yes, Java (similar to other mainstream languages) uses lazy evaluation short-circuiting which means it evaluates as little as possible.
This means that the following code is completely safe:
if(p != null && p.getAge() > 10)
Also, a || b never evaluates b if a evaluates to true.
set font size in jquery
You can try another way like that:
<div class="content">
Australia
</div>
jQuery code:
$(".content").css({
background: "#d1d1d1",
fontSize: "30px"
})
Now you can add more css property as you want.
Pygame mouse clicking detection
I assume your game has a main loop, and all your sprites are in a list called sprites.
In your main loop, get all events, and check for the MOUSEBUTTONDOWN or MOUSEBUTTONUP event.
while ... # your main loop
# get all events
ev = pygame.event.get()
# proceed events
for event in ev:
# handle MOUSEBUTTONUP
if event.type == pygame.MOUSEBUTTONUP:
pos = pygame.mouse.get_pos()
# get a list of all sprites that are under the mouse cursor
clicked_sprites = [s for s in sprites if s.rect.collidepoint(pos)]
# do something with the clicked sprites...
So basically you have to check for a click on a sprite yourself every iteration of the mainloop. You'll want to use mouse.get_pos() and rect.collidepoint().
Pygame does not offer event driven programming, as e.g. cocos2d does.
Another way would be to check the position of the mouse cursor and the state of the pressed buttons, but this approach has some issues.
if pygame.mouse.get_pressed()[0] and mysprite.rect.collidepoint(pygame.mouse.get_pos()):
print ("You have opened a chest!")
You'll have to introduce some kind of flag if you handled this case, since otherwise this code will print "You have opened a chest!" every iteration of the main loop.
handled = False
while ... // your loop
if pygame.mouse.get_pressed()[0] and mysprite.rect.collidepoint(pygame.mouse.get_pos()) and not handled:
print ("You have opened a chest!")
handled = pygame.mouse.get_pressed()[0]
Of course you can subclass Sprite and add a method called is_clicked like this:
class MySprite(Sprite):
...
def is_clicked(self):
return pygame.mouse.get_pressed()[0] and self.rect.collidepoint(pygame.mouse.get_pos())
So, it's better to use the first approach IMHO.
Split string into string array of single characters
string input = "this is a test";
string[] afterSplit = input.Split();
foreach (var word in afterSplit)
Console.WriteLine(word);
Result:
this
is
a
test
If input field is empty, disable submit button
For those that use coffeescript, I've put the code we use globally to disable the submit buttons on our most widely used form. An adaption of Adil's answer above.
$('#new_post button').prop 'disabled', true
$('#new_post #post_message').keyup ->
$('#new_post button').prop 'disabled', if @value == '' then true else false
return
Generating CSV file for Excel, how to have a newline inside a value
Normally a new line is "\r\n". In my CSV, I replaced "\r" with empty value. Here is code in Javascript:
cellValue = cellValue.replace(/\r/g, "")
When I open the CSV in MS Excel, it worked well. If a value has multiple lines, it will stay within 1 single cell in the Excel sheet.
Unable to import path from django.urls
The reason you cannot import path is because it is new in Django 2.0 as is mentioned here: https://docs.djangoproject.com/en/2.0/ref/urls/#path.
On that page in the bottom right hand corner you can change the documentation version to the version that you have installed. If you do this you will see that there is no entry for path on the 1.11 docs.
Remove unwanted parts from strings in a column
How do I remove unwanted parts from strings in a column?
6 years after the original question was posted, pandas now has a good number of "vectorised" string functions that can succinctly perform these string manipulation operations.
This answer will explore some of these string functions, suggest faster alternatives, and go into a timings comparison at the end.
.str.replace
Specify the substring/pattern to match, and the substring to replace it with.
pd.__version__
# '0.24.1'
df
time result
1 09:00 +52A
2 10:00 +62B
3 11:00 +44a
4 12:00 +30b
5 13:00 -110a
df['result'] = df['result'].str.replace(r'\D', '')
df
time result
1 09:00 52
2 10:00 62
3 11:00 44
4 12:00 30
5 13:00 110
If you need the result converted to an integer, you can use Series.astype,
df['result'] = df['result'].str.replace(r'\D', '').astype(int)
df.dtypes
time object
result int64
dtype: object
If you don't want to modify df in-place, use DataFrame.assign:
df2 = df.assign(result=df['result'].str.replace(r'\D', ''))
df
# Unchanged
.str.extract
Useful for extracting the substring(s) you want to keep.
df['result'] = df['result'].str.extract(r'(\d+)', expand=False)
df
time result
1 09:00 52
2 10:00 62
3 11:00 44
4 12:00 30
5 13:00 110
With extract, it is necessary to specify at least one capture group. expand=False will return a Series with the captured items from the first capture group.
.str.split and .str.get
Splitting works assuming all your strings follow this consistent structure.
# df['result'] = df['result'].str.split(r'\D').str[1]
df['result'] = df['result'].str.split(r'\D').str.get(1)
df
time result
1 09:00 52
2 10:00 62
3 11:00 44
4 12:00 30
5 13:00 110
Do not recommend if you are looking for a general solution.
If you are satisfied with the succinct and readable
straccessor-based solutions above, you can stop here. However, if you are interested in faster, more performant alternatives, keep reading.
Optimizing: List Comprehensions
In some circumstances, list comprehensions should be favoured over pandas string functions. The reason is because string functions are inherently hard to vectorize (in the true sense of the word), so most string and regex functions are only wrappers around loops with more overhead.
My write-up, Are for-loops in pandas really bad? When should I care?, goes into greater detail.
The str.replace option can be re-written using re.sub
import re
# Pre-compile your regex pattern for more performance.
p = re.compile(r'\D')
df['result'] = [p.sub('', x) for x in df['result']]
df
time result
1 09:00 52
2 10:00 62
3 11:00 44
4 12:00 30
5 13:00 110
The str.extract example can be re-written using a list comprehension with re.search,
p = re.compile(r'\d+')
df['result'] = [p.search(x)[0] for x in df['result']]
df
time result
1 09:00 52
2 10:00 62
3 11:00 44
4 12:00 30
5 13:00 110
If NaNs or no-matches are a possibility, you will need to re-write the above to include some error checking. I do this using a function.
def try_extract(pattern, string):
try:
m = pattern.search(string)
return m.group(0)
except (TypeError, ValueError, AttributeError):
return np.nan
p = re.compile(r'\d+')
df['result'] = [try_extract(p, x) for x in df['result']]
df
time result
1 09:00 52
2 10:00 62
3 11:00 44
4 12:00 30
5 13:00 110
We can also re-write @eumiro's and @MonkeyButter's answers using list comprehensions:
df['result'] = [x.lstrip('+-').rstrip('aAbBcC') for x in df['result']]
And,
df['result'] = [x[1:-1] for x in df['result']]
Same rules for handling NaNs, etc, apply.
Performance Comparison
Graphs generated using perfplot. Full code listing, for your reference. The relevant functions are listed below.
Some of these comparisons are unfair because they take advantage of the structure of OP's data, but take from it what you will. One thing to note is that every list comprehension function is either faster or comparable than its equivalent pandas variant.
Functions
def eumiro(df): return df.assign( result=df['result'].map(lambda x: x.lstrip('+-').rstrip('aAbBcC'))) def coder375(df): return df.assign( result=df['result'].replace(r'\D', r'', regex=True)) def monkeybutter(df): return df.assign(result=df['result'].map(lambda x: x[1:-1])) def wes(df): return df.assign(result=df['result'].str.lstrip('+-').str.rstrip('aAbBcC')) def cs1(df): return df.assign(result=df['result'].str.replace(r'\D', '')) def cs2_ted(df): # `str.extract` based solution, similar to @Ted Petrou's. so timing together. return df.assign(result=df['result'].str.extract(r'(\d+)', expand=False)) def cs1_listcomp(df): return df.assign(result=[p1.sub('', x) for x in df['result']]) def cs2_listcomp(df): return df.assign(result=[p2.search(x)[0] for x in df['result']]) def cs_eumiro_listcomp(df): return df.assign( result=[x.lstrip('+-').rstrip('aAbBcC') for x in df['result']]) def cs_mb_listcomp(df): return df.assign(result=[x[1:-1] for x in df['result']])
Does Hive have a String split function?
Another interesting usecase for split in Hive is when, for example, a column ipname in the table has a value "abc11.def.ghft.com" and you want to pull "abc11" out:
SELECT split(ipname,'[\.]')[0] FROM tablename;
jQuery: find element by text
Yes, use the jQuery contains selector.
Google Spreadsheet, Count IF contains a string
In case someone is still looking for the answer, this worked for me:
=COUNTIF(A2:A51, "*" & B1 & "*")
B1 containing the iPad string.
What is the purpose of the single underscore "_" variable in Python?
There are 5 cases for using the underscore in Python.
For storing the value of last expression in interpreter.
For ignoring the specific values. (so-called “I don’t care”)
To give special meanings and functions to name of variables or functions.
To use as ‘internationalization (i18n)’ or ‘localization (l10n)’ functions.
To separate the digits of number literal value.
Here is a nice article with examples by mingrammer.
Python Loop: List Index Out of Range
When you call for i in a:, you are getting the actual elements, not the indexes. When we reach the last element, that is 3, b.append(a[i+1]-a[i]) looks for a[4], doesn't find one and then fails. Instead, try iterating over the indexes while stopping just short of the last one, like
for i in range(0, len(a)-1): Do something
Your current code won't work yet for the do something part though ;)
Find text string using jQuery?
jQuery has the contains method. Here's a snippet for you:
<script type="text/javascript">
$(function() {
var foundin = $('*:contains("I am a simple string")');
});
</script>
The selector above selects any element that contains the target string. The foundin will be a jQuery object that contains any matched element. See the API information at: https://api.jquery.com/contains-selector/
One thing to note with the '*' wildcard is that you'll get all elements, including your html an body elements, which you probably don't want. That's why most of the examples at jQuery and other places use $('div:contains("I am a simple string")')
JQuery $.ajax() post - data in a java servlet
For the time being I am going a different route than I previous stated. I changed the way I am formatting the data to:
&A2168=1&A1837=5&A8472=1&A1987=2
On the server side I am using getParameterNames() to place all the keys into an Enumerator and then iterating over the Enumerator and placing the keys and values into a HashMap. It looks something like this:
Enumeration keys = request.getParameterNames();
HashMap map = new HashMap();
String key = null;
while(keys.hasMoreElements()){
key = keys.nextElement().toString();
map.put(key, request.getParameter(key));
}
Random color generator
This line should randomly change the color for you:
setInterval(function(){y.style.color=''+"rgb(1"+Math.floor(Math.random() * 100)+",1"+Math.floor(Math.random() * 100)+",1"+Math.floor(Math.random() * 100)+")"+'';},1000);
Node.js: How to read a stream into a buffer?
You can convert your readable stream to a buffer and integrate it in your code in an asynchronous way like this.
async streamToBuffer (stream) {
return new Promise((resolve, reject) => {
const data = [];
stream.on('data', (chunk) => {
data.push(chunk);
});
stream.on('end', () => {
resolve(Buffer.concat(data))
})
stream.on('error', (err) => {
reject(err)
})
})
}
the usage would be as simple as:
// usage
const myStream // your stream
const buffer = await streamToBuffer(myStream) // this is a buffer
'System.Reflection.TargetInvocationException' occurred in PresentationFramework.dll
The event is probably raised before the elements are fully loaded or the references are still unset, hence the exceptions. Try only setting properties if the reference is not null and IsLoaded is true.
Map vs Object in JavaScript
The key difference is that Objects only support string and Symbol keys where as Maps support more or less any key type.
If I do obj[123] = true and then Object.keys(obj) then I will get ["123"] rather than [123]. A Map would preserve the type of the key and return [123] which is great. Maps also allow you to use Objects as keys. Traditionally to do this you would have to give objects some kind of unique identifier to hash them (I don't think I've ever seen anything like getObjectId in JS as part of the standard). Maps also guarantee preservation of order so are all round better for preservation and can sometimes save you needing to do a few sorts.
Between maps and objects in practice there are several pros and cons. Objects gain both advantages and disadvantages being very tightly integrated into the core of JavaScript which sets them apart from significantly Map beyond the difference in key support.
An immediate advantage is that you have syntactical support for Objects making it easy to access elements. You also have direct support for it with JSON. When used as a hash it's annoying to get an object without any properties at all. By default if you want to use Objects as a hash table they will be polluted and you will often have to call hasOwnProperty on them when accessing properties. You can see here how by default Objects are polluted and how to create hopefully unpolluted objects for use as hashes:
({}).toString
toString() { [native code] }
JSON.parse('{}').toString
toString() { [native code] }
(Object.create(null)).toString
undefined
JSON.parse('{}', (k,v) => (typeof v === 'object' && Object.setPrototypeOf(v, null) ,v)).toString
undefined
Pollution on objects is not only something that makes code more annoying, slower, etc but can also have potential consequences for security.
Objects are not pure hash tables but are trying to do more. You have headaches like hasOwnProperty, not being able to get the length easily (Object.keys(obj).length) and so on. Objects are not meant to purely be used as hash maps but as dynamic extensible Objects as well and so when you use them as pure hash tables problems arise.
Comparison/List of various common operations:
Object:
var o = {};
var o = Object.create(null);
o.key = 1;
o.key += 10;
for(let k in o) o[k]++;
var sum = 0;
for(let v of Object.values(m)) sum += v;
if('key' in o);
if(o.hasOwnProperty('key'));
delete(o.key);
Object.keys(o).length
Map:
var m = new Map();
m.set('key', 1);
m.set('key', m.get('key') + 10);
m.foreach((k, v) => m.set(k, m.get(k) + 1));
for(let k of m.keys()) m.set(k, m.get(k) + 1);
var sum = 0;
for(let v of m.values()) sum += v;
if(m.has('key'));
m.delete('key');
m.size();
There are a few other options, approaches, methodologies, etc with varying ups and downs (performance, terse, portable, extendable, etc). Objects are a bit strange being core to the language so you have a lot of static methods for working with them.
Besides the advantage of Maps preserving key types as well as being able to support things like objects as keys they are isolated from the side effects that objects much have. A Map is a pure hash, there's no confusion about trying to be an object at the same time. Maps can also be easily extended with proxy functions. Object's currently have a Proxy class however performance and memory usage is grim, in fact creating your own proxy that looks like Map for Objects currently performs better than Proxy.
A substantial disadvantage for Maps is that they are not supported with JSON directly. Parsing is possible but has several hangups:
JSON.parse(str, (k,v) => {
if(typeof v !== 'object') return v;
let m = new Map();
for(k in v) m.set(k, v[k]);
return m;
});
The above will introduce a serious performance hit and will also not support any string keys. JSON encoding is even more difficult and problematic (this is one of many approaches):
// An alternative to this it to use a replacer in JSON.stringify.
Map.prototype.toJSON = function() {
return JSON.stringify({
keys: Array.from(this.keys()),
values: Array.from(this.values())
});
};
This is not so bad if you're purely using Maps but will have problems when you are mixing types or using non-scalar values as keys (not that JSON is perfect with that kind of issue as it is, IE circular object reference). I haven't tested it but chances are that it will severely hurt performance compared to stringify.
Other scripting languages often don't have such problems as they have explicit non-scalar types for Map, Object and Array. Web development is often a pain with non-scalar types where you have to deal with things like PHP merges Array/Map with Object using A/M for properties and JS merges Map/Object with Array extending M/O. Merging complex types is the devil's bane of high level scripting languages.
So far these are largely issues around implementation but performance for basic operations is important as well. Performance is also complex because it depends on engine and usage. Take my tests with a grain of salt as I cannot rule out any mistake (I have to rush this). You should also run your own tests to confirm as mine examine only very specific simple scenarios to give a rough indication only. According to tests in Chrome for very large objects/maps the performance for objects is worse because of delete which is apparently somehow proportionate to the number of keys rather than O(1):
Object Set Took: 146
Object Update Took: 7
Object Get Took: 4
Object Delete Took: 8239
Map Set Took: 80
Map Update Took: 51
Map Get Took: 40
Map Delete Took: 2
Chrome clearly has a strong advantage with getting and updating but the delete performance is horrific. Maps use a tiny amount more memory in this case (overhead) but with only one Object/Map being tested with millions of keys the impact of overhead for maps is not expressed well. With memory management objects also do seem to free earlier if I am reading the profile correctly which might be one benefit in favor of objects.
In Firefox for this particular benchmark it is a different story:
Object Set Took: 435
Object Update Took: 126
Object Get Took: 50
Object Delete Took: 2
Map Set Took: 63
Map Update Took: 59
Map Get Took: 33
Map Delete Took: 1
I should immediately point out that in this particular benchmark deleting from objects in Firefox is not causing any problems, however in other benchmarks it has caused problems especially when there are many keys just as in Chrome. Maps are clearly superior in Firefox for large collections.
However this is not the end of the story, what about many small objects or maps? I have done a quick benchmark of this but not an exhaustive one (setting/getting) of which performs best with a small number of keys in the above operations. This test is more about memory and initialization.
Map Create: 69 // new Map
Object Create: 34 // {}
Again these figures vary but basically Object has a good lead. In some cases the lead for Objects over maps is extreme (~10 times better) but on average it was around 2-3 times better. It seems extreme performance spikes can work both ways. I only tested this in Chrome and creation to profile memory usage and overhead. I was quite surprised to see that in Chrome it appears that Maps with one key use around 30 times more memory than Objects with one key.
For testing many small objects with all the above operations (4 keys):
Chrome Object Took: 61
Chrome Map Took: 67
Firefox Object Took: 54
Firefox Map Took: 139
In terms of memory allocation these behaved the same in terms of freeing/GC but Map used 5 times more memory. This test used 4 keys where as in the last test I only set one key so this would explain the reduction in memory overhead. I ran this test a few times and Map/Object are more or less neck and neck overall for Chrome in terms of overall speed. In Firefox for small Objects there is a definite performance advantage over maps overall.
This of course doesn't include the individual options which could vary wildly. I would not advice micro-optimizing with these figures. What you can get out of this is that as a rule of thumb, consider Maps more strongly for very large key value stores and objects for small key value stores.
Beyond that the best strategy with these two it to implement it and just make it work first. When profiling it is important to keep in mind that sometimes things that you wouldn't think would be slow when looking at them can be incredibly slow because of engine quirks as seen with the object key deletion case.
ERROR Source option 1.5 is no longer supported. Use 1.6 or later
You need to set JDK 1.5 to your project and also all dependent project or jar file should also compiled with JDK 1.5
How to reset the state of a Redux store?
Simply have your logout link clear session and refresh the page. No additional code needed for your store. Any time you want to completely reset the state a page refresh is a simple and easily repeatable way to handle it.
how to include js file in php?
Its more likely that the path to file.js from the page is what is wrong. as long as when you view the page, and view-source you see the tag, its working, now its time to debug whether or not your path is too relative, maybe you need a / in front of it.
jQuery plugin returning "Cannot read property of undefined"
I had same problem with 'parallax' plugin.
I changed jQuery librery version to *jquery-1.6.4* from *jquery-1.10.2*.
And error cleared.
How to use java.Set
Since it is a HashSet you will need to override hashCode and equals methods. http://preciselyconcise.com/java/collections/d_set.php has an example explaining how to implement hashCode and equals methods
MySQL - force not to use cache for testing speed of query
I'd Use the following:
SHOW VARIABLES LIKE 'query_cache_type';
SET SESSION query_cache_type = OFF;
SHOW VARIABLES LIKE 'query_cache_type';
What is the best way to determine a session variable is null or empty in C#?
If you know it's a string, you can use the String.IsEmptyOrNull() function.
JavaScript check if variable exists (is defined/initialized)
The highest answer is correct, use typeof.
However, what I wanted to point out was that in JavaScript undefined is mutable (for some ungodly reason). So simply doing a check for varName !== undefined has the potential to not always return as you expect it to, because other libs could have changed undefined. A few answers (@skalee's, for one), seem to prefer not using typeof, and that could get one into trouble.
The "old" way to handle this was declaring undefined as a var to offset any potential muting/over-riding of undefined. However, the best way is still to use typeof because it will ignore any overriding of undefined from other code. Especially if you are writing code for use in the wild where who knows what else could be running on the page...
Writing a dict to txt file and reading it back?
Hi there is a way to write and read the dictionary to file you can turn your dictionary to JSON format and read and write quickly just do this :
To write your date:
import json
your_dictionary = {"some_date" : "date"}
f = open('destFile.txt', 'w+')
f.write(json.dumps(your_dictionary))
and to read your data:
import json
f = open('destFile.txt', 'r')
your_dictionary = json.loads(f.read())
Can inner classes access private variables?
Anything that is part of Outer should have access to all of Outer's members, public or private.
Edit: your compiler is correct, var is not a member of Inner. But if you have a reference or pointer to an instance of Outer, it could access that.
Listening for variable changes in JavaScript
In my case, I was trying to find out if any library I was including in my project was redefining my window.player. So, at the begining of my code, I just did:
Object.defineProperty(window, 'player', {
get: () => this._player,
set: v => {
console.log('window.player has been redefined!');
this._player = v;
}
});
Expression must be a modifiable L-value
lvalue means "left value" -- it should be assignable. You cannot change the value of text since it is an array, not a pointer.
Either declare it as char pointer (in this case it's better to declare it as const char*):
const char *text;
if(number == 2)
text = "awesome";
else
text = "you fail";
Or use strcpy:
char text[60];
if(number == 2)
strcpy(text, "awesome");
else
strcpy(text, "you fail");
Can you "compile" PHP code and upload a binary-ish file, which will just be run by the byte code interpreter?
There are several "compilers" of PHP code. Most of them do not support all of PHP features, since these simply must be interpreted during run time.
We are using Phalanger - http://www.php-compiler.net/ - that is supporting even those dirty PHP dynamic features, and still is able to compile them as .NET assembly, that can be distributed as a standalone DLL.
How can I make IntelliJ IDEA update my dependencies from Maven?
Apart from checking 'Import Maven projects automatically', make sure that settings.xml file from File > Settings > Maven > User Settings file exist, If doesn't exist then override and provide your settings.xml file path.
ASP.NET MVC - Attaching an entity of type 'MODELNAME' failed because another entity of the same type already has the same primary key value
for me the local copy was the source of the problem. this solved it
var local = context.Set<Contact>().Local.FirstOrDefault(c => c.ContactId == contact.ContactId);
if (local != null)
{
context.Entry(local).State = EntityState.Detached;
}
Can you style html form buttons with css?
You might want to add:
-webkit-appearance: none;
if you need it looking consistent on Mobile Safari...
org.hibernate.QueryException: could not resolve property: filename
Hibernate queries are case sensitive with property names (because they end up relying on getter/setter methods on the @Entity).
Make sure you refer to the property as fileName in the Criteria query, not filename.
Specifically, Hibernate will call the getter method of the filename property when executing that Criteria query, so it will look for a method called getFilename(). But the property is called FileName and the getter getFileName().
So, change the projection like so:
criteria.setProjection(Projections.property("fileName"));
Delete all rows in table
As other have said, TRUNCATE TABLE is far quicker, but it does have some restrictions (taken from here):
You cannot use TRUNCATE TABLE on tables that:
- Are referenced by a FOREIGN KEY constraint. (You can truncate a table that has a foreign key that references itself.)
- Participate in an indexed view.
- Are published by using transactional replication or merge replication.
For tables with one or more of these characteristics, use the DELETE statement instead.
The biggest drawback is that if the table you are trying to empty has foreign keys pointing to it, then the truncate call will fail.
Insert line break inside placeholder attribute of a textarea?
Salaamun Alekum
Works For Google Chrome
<textarea placeholder="Enter Choice#1 Enter Choice#2 Enter Choice#3"></textarea>
I Tested This On Windows 10.0 (Build 10240) And Google Chrome Version 47.0.2526.80 m
08:43:08 AST 6 Rabi Al-Awwal, 1437 Thursday, 17 December 2015
Thank You
Using ListView : How to add a header view?
You simply can't use View as a Header of ListView.
Because the view which is being passed in has to be inflated.
Look at my answer at Android ListView addHeaderView() nullPointerException for predefined Views for more info.
EDIT:
Look at this tutorial Android ListView and ListActivity - Tutorial .
EDIT 2: This link is broken Android ListActivity with a header or footer
Format Date time in AngularJS
Here are a few popular examples:
<div>{{myDate | date:'M/d/yyyy'}}</div> 7/4/2014
<div>{{myDate | date:'yyyy-MM-dd'}}</div> 2014-07-04
<div>{{myDate | date:'M/d/yyyy HH:mm:ss'}}</div> 7/4/2014 12:01:59
How to convert FormData (HTML5 object) to JSON
Even though the answer from @dzuc is already very good, you could use array destructuring (available in modern browsers or with Babel) to make it even a bit more elegant:
// original version from @dzuc
const data = Array.from(formData.entries())
.reduce((memo, pair) => ({
...memo,
[pair[0]: pair[1],
}), {})
// with array destructuring
const data = Array.from(formData.entries())
.reduce((memo,[key, value]) => ({
...memo,
[key]: value,
}), {})
Add up a column of numbers at the Unix shell
sizes=( $(cat files.txt | xargs ls -l | cut -c 23-30) )
total=$(( $(IFS="+"; echo "${sizes[*]}") ))
Or you could just sum them as you read the sizes
declare -i total=0
while read x; total+=x; done < <( cat files.txt | xargs ls -l | cut -c 23-30 )
If you don't care about bite sizes and blocks is OK, then just
declare -i total=0
while read s junk; total+=s; done < <( cat files.txt | xargs ls -s )
Adjust width of input field to its input
Quite simple:
oninput='this.style.width = (this.scrollWidth - N) + "px";'
Where N is some number (2 in the example, 17 on something I'm developing) that is determined experimentally.
Subtracting N prevents this strange extrenuous space from accumulating long before the text reaches the end of the text box.
Compare. Pay careful attention to how the size changes after even just the first character.
<p>Subtracting N:</p> _x000D_
<input type="text" placeholder="enter lots of text here" oninput='this.style.width = (this.scrollWidth-2) + "px";'>_x000D_
_x000D_
<p>Not Subtracting N:</p> _x000D_
<input type="text" placeholder="enter lots of text here" oninput='this.style.width = (this.scrollWidth) + "px";'>What is ViewModel in MVC?
If you have properties specific to the view, and not related to the DB/Service/Data store, it is a good practice to use ViewModels. Say, you want to leave a checkbox selected based on a DB field (or two) but the DB field itself isn't a boolean. While it is possible to create these properties in the Model itself and keep it hidden from the binding to data, you may not want to clutter the Model depending on the amount of such fields and transactions.
If there are too few view-specific data and/or transformations, you can use the Model itself
Add a custom attribute to a Laravel / Eloquent model on load?
The last thing on the Laravel Eloquent doc page is:
protected $appends = array('is_admin');
That can be used automatically to add new accessors to the model without any additional work like modifying methods like ::toArray().
Just create getFooBarAttribute(...) accessor and add the foo_bar to $appends array.
Installing a plain plugin jar in Eclipse 3.5
go to Help -> Install New Software... -> Add -> Archive.... Done.
Get index of current item in a PowerShell loop
For those coming here from Google like I did, later versions of Powershell have a $foreach automatic variable. You can find the "current" object with $foreach.Current
What does auto do in margin:0 auto?
When you have specified a width on the object that you have applied margin: 0 auto to, the object will sit centrally within it's parent container.
Specifying auto as the second parameter basically tells the browser to automatically determine the left and right margins itself, which it does by setting them equally. It guarantees that the left and right margins will be set to the same size. The first parameter 0 indicates that the top and bottom margins will both be set to 0.
margin-top:0;
margin-bottom:0;
margin-left:auto;
margin-right:auto;
Therefore, to give you an example, if the parent is 100px and the child is 50px, then the auto property will determine that there's 50px of free space to share between margin-left and margin-right:
var freeSpace = 100 - 50;
var equalShare = freeSpace / 2;
Which would give:
margin-left:25;
margin-right:25;
Have a look at this jsFiddle. You do not have to specify the parent width, only the width of the child object.
Pass props in Link react-router
After install react-router-dom
<Link
to={{
pathname: "/product-detail",
productdetailProps: {
productdetail: "I M passed From Props"
}
}}>
Click To Pass Props
</Link>
and other end where the route is redirected do this
componentDidMount() {
console.log("product props is", this.props.location.productdetailProps);
}
Saving a select count(*) value to an integer (SQL Server)
select @myInt = COUNT(*) from myTable
What's the difference between <mvc:annotation-driven /> and <context:annotation-config /> in servlet?
<context:annotation-config> declares support for general annotations such as @Required, @Autowired, @PostConstruct, and so on.
<mvc:annotation-driven /> declares explicit support for annotation-driven MVC controllers (i.e. @RequestMapping, @Controller, although support for those is the default behaviour), as well as adding support for declarative validation via @Valid and message body marshalling with @RequestBody/ResponseBody.
LaTeX table too wide. How to make it fit?
You have to take whole columns under resizebox. This code worked for me
\begin{table}[htbp]
\caption{Sample Table.}\label{tab1}
\resizebox{\columnwidth}{!}{\begin{tabular}{|l|l|l|l|l|}
\hline
URL & First Time Visit & Last Time Visit & URL Counts & Value\\
\hline
https://web.facebook.com/ & 1521241972 & 1522351859 & 177 & 56640\\
http://localhost/phpmyadmin/ & 1518413861 & 1522075694 & 24 & 39312\\
https://mail.google.com/mail/u/ & 1516596003 & 1522352010 & 36 & 33264\\
https://github.com/shawon100& 1517215489 & 1522352266 & 37 & 27528\\
https://www.youtube.com/ & 1517229227 & 1521978502 & 24 & 14792\\
\hline
\end{tabular}}
\end{table}
How do I properly clean up Excel interop objects?
First - you never have to call Marshal.ReleaseComObject(...) or Marshal.FinalReleaseComObject(...) when doing Excel interop. It is a confusing anti-pattern, but any information about this, including from Microsoft, that indicates you have to manually release COM references from .NET is incorrect. The fact is that the .NET runtime and garbage collector correctly keep track of and clean up COM references. For your code, this means you can remove the whole `while (...) loop at the top.
Second, if you want to ensure that the COM references to an out-of-process COM object are cleaned up when your process ends (so that the Excel process will close), you need to ensure that the garbage collector runs. You do this correctly with calls to GC.Collect() and GC.WaitForPendingFinalizers(). Calling this twice is safe, and ensures that cycles are definitely cleaned up too (though I'm not sure it's needed, and would appreciate an example that shows this).
Third, when running under the debugger, local references will be artificially kept alive until the end of the method (so that local variable inspection works). So GC.Collect() calls are not effective for cleaning object like rng.Cells from the same method. You should split the code doing the COM interop from the GC cleanup into separate methods. (This was a key discovery for me, from one part of the answer posted here by @nightcoder.)
The general pattern would thus be:
Sub WrapperThatCleansUp()
' NOTE: Don't call Excel objects in here...
' Debugger would keep alive until end, preventing GC cleanup
' Call a separate function that talks to Excel
DoTheWork()
' Now let the GC clean up (twice, to clean up cycles too)
GC.Collect()
GC.WaitForPendingFinalizers()
GC.Collect()
GC.WaitForPendingFinalizers()
End Sub
Sub DoTheWork()
Dim app As New Microsoft.Office.Interop.Excel.Application
Dim book As Microsoft.Office.Interop.Excel.Workbook = app.Workbooks.Add()
Dim worksheet As Microsoft.Office.Interop.Excel.Worksheet = book.Worksheets("Sheet1")
app.Visible = True
For i As Integer = 1 To 10
worksheet.Cells.Range("A" & i).Value = "Hello"
Next
book.Save()
book.Close()
app.Quit()
' NOTE: No calls the Marshal.ReleaseComObject() are ever needed
End Sub
There is a lot of false information and confusion about this issue, including many posts on MSDN and on Stack Overflow (and especially this question!).
What finally convinced me to have a closer look and figure out the right advice was blog post Marshal.ReleaseComObject Considered Dangerous together with finding the issue with references kept alive under the debugger that was confusing my earlier testing.
ViewBag, ViewData and TempData
ASP.NET MVC offers us three options ViewData, ViewBag, and TempData for passing data from controller to view and in next request. ViewData and ViewBag are almost similar and TempData performs additional responsibility. Lets discuss or get key points on those three objects:
Similarities between ViewBag & ViewData :
- Helps to maintain data when you move from controller to view.
- Used to pass data from controller to corresponding view.
- Short life means value becomes null when redirection occurs. This is because their goal is to provide a way to communicate between controllers and views. It’s a communication mechanism within the server call.
Difference between ViewBag & ViewData:
- ViewData is a dictionary of objects that is derived from ViewDataDictionary class and accessible using strings as keys.
- ViewBag is a dynamic property that takes advantage of the new dynamic features in C# 4.0.
- ViewData requires typecasting for complex data type and check for null values to avoid error.
- ViewBag doesn’t require typecasting for complex data type.
ViewBag & ViewData Example:
public ActionResult Index()
{
ViewBag.Name = "Monjurul Habib";
return View();
}
public ActionResult Index()
{
ViewData["Name"] = "Monjurul Habib";
return View();
}
In View:
@ViewBag.Name
@ViewData["Name"]
TempData:
TempData is also a dictionary derived from TempDataDictionary class and stored in short lives session and it is a string key and object value. The difference is that the life cycle of the object. TempData keep the information for the time of an HTTP Request. This mean only from one page to another. This also work with a 302/303 redirection because it’s in the same HTTP Request. Helps to maintain data when you move from one controller to other controller or from one action to other action. In other words when you redirect, “TempData” helps to maintain data between those redirects. It internally uses session variables. Temp data use during the current and subsequent request only means it is use when you are sure that next request will be redirecting to next view. It requires typecasting for complex data type and check for null values to avoid error. Generally used to store only one time messages like error messages, validation messages.
public ActionResult Index()
{
var model = new Review()
{
Body = "Start",
Rating=5
};
TempData["ModelName"] = model;
return RedirectToAction("About");
}
public ActionResult About()
{
var model= TempData["ModelName"];
return View(model);
}
The last mechanism is the Session which work like the ViewData, like a Dictionary that take a string for key and object for value. This one is stored into the client Cookie and can be used for a much more long time. It also need more verification to never have any confidential information. Regarding ViewData or ViewBag you should use it intelligently for application performance. Because each action goes through the whole life cycle of regular asp.net mvc request. You can use ViewData/ViewBag in your child action but be careful that you are not using it to populate the unrelated data which can pollute your controller.
Difference between style = "position:absolute" and style = "position:relative"
Relative:
An element with
position: relative;is positioned relative to its normal position.If you add no positioning attributes (top, left, bottom or right) on a relative element it will have no effect on it's positioning at all. It will behave exactly as a
position: staticelement.But if you do add some other positioning attribute, say, top: 10px;, it will shift its position 10 pixels down from where it would normally be.
An element with this type of positioning gets affected by other elements and it itself also affects others.
Absolute:
An element with
position: absolute;allows you to place any element exactly where you want it to be. You use the positioning attributes top, left, bottom. and right to set the location.It is placed relative to the nearest non-static ancestor. If there is no such container, it is placed relative to the page itself.
It gets removed from the normal flow of elements on the page.
An element with this type of positioning is not affected by other elements and also it doesn't affect flow of other elements.
See this self-explanatory example for better clarity. https://codepen.io/nyctophiliac/pen/BJMqjX
Get the date (a day before current time) in Bash
Use Perl instead perhaps?
perl -e 'print scalar localtime( time - 86400 ) . "\n";'
Or, use nawk and (ab)use /usr/bin/adb:
nawk 'BEGIN{printf "0t%d=Y\n", srand()-86400}' | adb
Came across this too ... insane!
/usr/bin/truss /usr/bin/date 2>&1 | nawk -F= '/^time\(\)/ {gsub(/ /,"",$2);printf "0t%d=Y\n", $2-86400}' | adb
Print to the same line and not a new line?
Late to the game - but since the none of the answers worked for me (I didn't try them all) and I've come upon this answer more than once in my search ... In python 3, this solution is pretty elegant and I believe does exactly what the author is looking for, it updates a single statement on the same line. Note, you may have to do something special if the line shrinks instead of grows (like perhaps make the string a fixed length with padded spaces at the end)
if __name__ == '__main__':
for i in range(100):
print("", end=f"\rPercentComplete: {i} %")
time.sleep(0.2)
Should IBOutlets be strong or weak under ARC?
I don't see any problem with that. Pre-ARC, I've always made my IBOutlets assign, as they're already retained by their superviews. If you make them weak, you shouldn't have to nil them out in viewDidUnload, as you point out.
One caveat: You can support iOS 4.x in an ARC project, but if you do, you can't use weak, so you'd have to make them assign, in which case you'd still want to nil the reference in viewDidUnload to avoid a dangling pointer. Here's an example of a dangling pointer bug I've experienced:
A UIViewController has a UITextField for zip code. It uses CLLocationManager to reverse geocode the user's location and set the zip code. Here's the delegate callback:
-(void)locationManager:(CLLocationManager *)manager
didUpdateToLocation:(CLLocation *)newLocation
fromLocation:(CLLocation *)oldLocation {
Class geocoderClass = NSClassFromString(@"CLGeocoder");
if (geocoderClass && IsEmpty(self.zip.text)) {
id geocoder = [[geocoderClass alloc] init];
[geocoder reverseGeocodeLocation:newLocation completionHandler:^(NSArray *placemarks, NSError *error) {
if (self.zip && IsEmpty(self.zip.text)) {
self.zip.text = [[placemarks objectAtIndex:0] postalCode];
}
}];
}
[self.locationManager stopUpdatingLocation];
}
I found that if I dismissed this view at the right time and didn't nil self.zip in viewDidUnload, the delegate callback could throw a bad access exception on self.zip.text.
Understanding the grid classes ( col-sm-# and col-lg-# ) in Bootstrap 3
This might be late as I think most of us are using BS4. This article explained all the questions you asked in a detailed and simple manner also includes what to do when. The detailed guide to use bs4 or bootstrap
https://uxplanet.org/how-the-bootstrap-4-grid-works-a1b04703a3b7
How to show one layout on top of the other programmatically in my case?
Use a FrameLayout with two children. The two children will be overlapped. This is recommended in one of the tutorials from Android actually, it's not a hack...
Here is an example where a TextView is displayed on top of an ImageView:
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ImageView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:scaleType="center"
android:src="@drawable/golden_gate" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="20dip"
android:layout_gravity="center_horizontal|bottom"
android:padding="12dip"
android:background="#AA000000"
android:textColor="#ffffffff"
android:text="Golden Gate" />
</FrameLayout>
Check if space is in a string
word = ' '
while True:
if ' ' in word:
word = raw_input("Please enter a single word: ")
else:
print "Thanks"
break
This is more idiomatic python - comparison against True or False is not necessary - just use the value returned by the expression ' ' in word.
Also, you don't need to use pastebin for such a small snippet of code - just copy the code into your post and use the little 1s and 0s button to make your code look like code.
Get the ID of a drawable in ImageView
I recently run into the same problem. I solved it by implementing my own ImageView class.
Here is my Kotlin implementation:
class MyImageView(context: Context): ImageView(context) {
private var currentDrawableId: Int? = null
override fun setImageResource(resId: Int) {
super.setImageResource(resId)
currentDrawableId = resId
}
fun getDrawableId() {
return currentDrawableId
}
fun compareCurrentDrawable(toDrawableId: Int?): Boolean {
if (toDrawableId == null || currentDrawableId != toDrawableId) {
return false
}
return true
}
}