Programs & Examples On #Onmouseover

OnMouseOver is an event which fires in a GUI framework when a user positions mouse cursor over a control.

Display Image On Text Link Hover CSS Only

I did something like that:

HTML:

<p class='parent'>text text text</p>
<img class='child' src='idk.png'>

CSS:

.child {
    visibility: hidden;
}

.parent:hover .child {
    visibility: visible;
}

How to run a javascript function during a mouseover on a div

Here's a jQuery solution.

<script type="text/javascript" src="/path/to/your/copy/of/jquery-1.3.2.min.js"></script>
<script type="text/javascript">
$(document).ready(function() {
    $("#sub1").mouseover(function() {
        $("#welcome").toggle();
    });
});
</script>

Using this markup:

<div id="sub1">some text</div>
<div id="welcome" style="display:none;">Welcome message</div>

You didn't really specify if (or when) you wanted to hide the welcome message, but this would toggle hiding or showing each time you moused over the text.

How to draw in JPanel? (Swing/graphics Java)

Note the extra comments.

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;

class JavaPaintUI extends JFrame {

    private int tool = 1;
    int currentX, currentY, oldX, oldY;

    public JavaPaintUI() {
        initComponents();
    }

    private void initComponents() {
        // we want a custom Panel2, not a generic JPanel!
        jPanel2 = new Panel2();

        jPanel2.setBackground(new java.awt.Color(255, 255, 255));
        jPanel2.setBorder(BorderFactory.createBevelBorder(BevelBorder.RAISED));
        jPanel2.addMouseListener(new MouseAdapter() {
            public void mousePressed(MouseEvent evt) {
                jPanel2MousePressed(evt);
            }
            public void mouseReleased(MouseEvent evt) {
                jPanel2MouseReleased(evt);
            }
        });
        jPanel2.addMouseMotionListener(new MouseMotionAdapter() {
            public void mouseDragged(MouseEvent evt) {
                jPanel2MouseDragged(evt);
            }
        });

        // add the component to the frame to see it!
        this.setContentPane(jPanel2);
        // be nice to testers..
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        pack();
    }// </editor-fold>

    private void jPanel2MouseDragged(MouseEvent evt) {
        if (tool == 1) {
            currentX = evt.getX();
            currentY = evt.getY();
            oldX = currentX;
            oldY = currentY;
            System.out.println(currentX + " " + currentY);
            System.out.println("PEN!!!!");
        }
    }

    private void jPanel2MousePressed(MouseEvent evt) {
        oldX = evt.getX();
        oldY = evt.getY();
        System.out.println(oldX + " " + oldY);
    }


    //mouse released//
    private void jPanel2MouseReleased(MouseEvent evt) {
        if (tool == 2) {
            currentX = evt.getX();
            currentY = evt.getY();
            System.out.println("line!!!! from" + oldX + "to" + currentX);
        }
    }

    //set ui visible//
    public static void main(String args[]) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                new JavaPaintUI().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify
    private JPanel jPanel2;
    // End of variables declaration

    // This class name is very confusing, since it is also used as the
    // name of an attribute!
    //class jPanel2 extends JPanel {
    class Panel2 extends JPanel {

        Panel2() {
            // set a preferred size for the custom panel.
            setPreferredSize(new Dimension(420,420));
        }

        @Override
        public void paintComponent(Graphics g) {
            super.paintComponent(g);

            g.drawString("BLAH", 20, 20);
            g.drawRect(200, 200, 200, 200);
        }
    }
}

Screen Shot

enter image description here

Other examples - more tailored to multiple lines & multiple line segments

HFOE put a good link as the first comment on this thread. Camickr also has a description of active painting vs. drawing to a BufferedImage in the Custom Painting Approaches article.

See also this approach using painting in a BufferedImage.

How to generate a random alpha-numeric string

public static String getRandomString(int length) {
    char[] chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRST".toCharArray();

    StringBuilder sb = new StringBuilder();
    Random random = new Random();
    for (int i = 0; i < length; i++) {
        char c = chars[random.nextInt(chars.length)];
        sb.append(c);
    }
    String randomStr = sb.toString();

    return randomStr;
}

Angular2 module has no exported member

In my module i am exporting classes this way:

export { SigninComponent } from './SigninComponent';
export { RegisterComponent } from './RegisterComponent';

This allow me to import multiple classes in file from same module:

import { SigninComponent, RegisterComponent} from "../auth.module";

PS: Of course @Fjut answer is correct, but same time it doesn't support multiple imports from same file. I would suggest to use both answers for your needs. But importing from module makes folder structure refactorings more easier.

Can I apply a CSS style to an element name?

if in case you are not using name in input but other element, then you can target other element with there attribute.

_x000D_
_x000D_
    [title~=flower] {_x000D_
      border: 5px solid yellow;_x000D_
    }
_x000D_
    <img src="klematis.jpg" title="klematis flower" width="150" height="113">_x000D_
    <img src="img_flwr.gif" title="flower" width="224" height="162">_x000D_
    <img src="img_flwr.gif" title="flowers" width="224" height="162">
_x000D_
_x000D_
_x000D_

hope its help. Thank you

iFrame src change event detection?

If you have no control over the page and wish to watch for some kind of change then the modern method is to use MutationObserver

An example of its use, watching for the src attribute to change of an iframe

_x000D_
_x000D_
new MutationObserver(function(mutations) {_x000D_
  mutations.some(function(mutation) {_x000D_
    if (mutation.type === 'attributes' && mutation.attributeName === 'src') {_x000D_
      console.log(mutation);_x000D_
      console.log('Old src: ', mutation.oldValue);_x000D_
      console.log('New src: ', mutation.target.src);_x000D_
      return true;_x000D_
    }_x000D_
_x000D_
    return false;_x000D_
  });_x000D_
}).observe(document.body, {_x000D_
  attributes: true,_x000D_
  attributeFilter: ['src'],_x000D_
  attributeOldValue: true,_x000D_
  characterData: false,_x000D_
  characterDataOldValue: false,_x000D_
  childList: false,_x000D_
  subtree: true_x000D_
});_x000D_
_x000D_
setTimeout(function() {_x000D_
  document.getElementsByTagName('iframe')[0].src = 'http://jsfiddle.net/';_x000D_
}, 3000);
_x000D_
<iframe src="http://www.google.com"></iframe>
_x000D_
_x000D_
_x000D_

Output after 3 seconds

MutationRecord {oldValue: "http://www.google.com", attributeNamespace: null, attributeName: "src", nextSibling: null, previousSibling: null…}
Old src:  http://www.google.com
New src:  http://jsfiddle.net/ 

On jsFiddle

Posted answer here as original question was closed as a duplicate of this one.

tmux status bar configuration

Do C-b, :show which will show you all your current settings. /green, nnn will find you which properties have been set to green, the default. Do C-b, :set window-status-bg cyan and the bottom bar should change colour.

List available colours for tmux

You can tell more easily by the titles and the colours as they're actually set in your live session :show, than by searching through the man page, in my opinion. It is a very well-written man page when you have the time though.

If you don't like one of your changes and you can't remember how it was originally set, you can open do a new tmux session. To change settings for good edit ~/.tmux.conf with a line like set window-status-bg -g cyan. Here's mine: https://gist.github.com/9083598

How to replace a whole line with sed?

Like this:

sed 's/aaa=.*/aaa=xxx/'

If you want to guarantee that the aaa= is at the start of the line, make it:

sed 's/^aaa=.*/aaa=xxx/'

How to use BeanUtils.copyProperties?

There are two BeanUtils.copyProperties(parameter1, parameter2) in Java.

One is

org.apache.commons.beanutils.BeanUtils.copyProperties(Object dest, Object orig)

Another is

org.springframework.beans.BeanUtils.copyProperties(Object source, Object target)

Pay attention to the opposite position of parameters.

What is the curl error 52 "empty reply from server"?

It happens when you are trying to access secure Website like Https.

I hope you missed 's'

Try Changing URL to curl -sS -u "username:password" https://www.example.com/backup.php

How to pick element inside iframe using document.getElementById

You need to make sure the frame is fully loaded the best way to do it is to use onload:

<iframe id="nesgt" src="" onload="custom()"></iframe>

function custom(){
    document.getElementById("nesgt").contentWindow.document;
    }

this function will run automatically when the iframe is fully loaded.

it could be done with setTimeout but we can't get the exact time of the frame load.

hope this helps someone.

Check if SQL Connection is Open or Closed

Here is what I'm using:

if (mySQLConnection.State != ConnectionState.Open)
{
    mySQLConnection.Close();
    mySQLConnection.Open();
}

The reason I'm not simply using:

if (mySQLConnection.State == ConnectionState.Closed)
{
    mySQLConnection.Open();
}

Is because the ConnectionState can also be:

Broken, Connnecting, Executing, Fetching

In addition to

Open, Closed

Additionally Microsoft states that Closing, and then Re-opening the connection "will refresh the value of State." See here http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqlconnection.state(v=vs.110).aspx

Undefined columns selected when subsetting data frame

You want rows where that condition is true so you need a comma:

data[data$Ozone > 14, ]

Easy way to test an LDAP User's Credentials

Authentication is done via a simple ldap_bind command that takes the users DN and the password. The user is authenticated when the bind is successfull. Usually you would get the users DN via an ldap_search based on the users uid or email-address.

Getting the users roles is something different as it is an ldap_search and depends on where and how the roles are stored in the ldap. But you might be able to retrieve the roles during the lap_search used to find the users DN.

What are all the possible values for HTTP "Content-Type" header?

As is defined in RFC 1341:

In the Extended BNF notation of RFC 822, a Content-Type header field value is defined as follows:

Content-Type := type "/" subtype *[";" parameter]

type := "application" / "audio" / "image" / "message" / "multipart" / "text" / "video" / x-token

x-token := < The two characters "X-" followed, with no intervening white space, by any token >

subtype := token

parameter := attribute "=" value

attribute := token

value := token / quoted-string

token := 1*

tspecials := "(" / ")" / "<" / ">" / "@" ; Must be in / "," / ";" / ":" / "\" / <"> ; quoted-string, / "/" / "[" / "]" / "?" / "." ; to use within / "=" ; parameter values

And a list of known MIME types that can follow it (or, as Joe remarks, the IANA source).

As you can see the list is way too big for you to validate against all of them. What you can do is validate against the general format and the type attribute to make sure that is correct (the set of options is small) and just assume that what follows it is correct (and of course catch any exceptions you might encounter when you put it to actual use).

Also note the comment above:

If another primary type is to be used for any reason, it must be given a name starting with "X-" to indicate its non-standard status and to avoid any potential conflict with a future official name.

You'll notice that a lot of HTTP requests/responses include an X- header of some sort which are self defined, keep this in mind when validating the types.

Repeat a string in JavaScript a number of times

Array(10).fill('a').join('')

Although the most voted answer is a bit more compact, with this approach you don't have to add an extra array item.

React fetch data in server before render

As a supplement of the answer of Michael Parker, you can make getData accept a callback function to active the setState update the data:

componentWillMount : function () {
    var data = this.getData(()=>this.setState({data : data}));
},

Best way to get all selected checkboxes VALUES in jQuery

You want the :checkbox:checked selector and map to create an array of the values:

var checkedValues = $('input:checkbox:checked').map(function() {
    return this.value;
}).get();

If your checkboxes have a shared class it would be faster to use that instead, eg. $('.mycheckboxes:checked'), or for a common name $('input[name="Foo"]:checked')

- Update -

If you don't need IE support then you can now make the map() call more succinct by using an arrow function:

var checkedValues = $('input:checkbox:checked').map((i, el) => el.value).get();

Converting std::__cxx11::string to std::string

Is it possible that you are using GCC 5?

If you get linker errors about undefined references to symbols that involve types in the std::__cxx11 namespace or the tag [abi:cxx11] then it probably indicates that you are trying to link together object files that were compiled with different values for the _GLIBCXX_USE_CXX11_ABI macro. This commonly happens when linking to a third-party library that was compiled with an older version of GCC. If the third-party library cannot be rebuilt with the new ABI then you will need to recompile your code with the old ABI.

Source: GCC 5 Release Notes/Dual ABI

Defining the following macro before including any standard library headers should fix your problem: #define _GLIBCXX_USE_CXX11_ABI 0

Generating Random Passwords

public string Sifre_Uret(int boy, int noalfa)
{

    //  01.03.2016   
    // Genel amaçli sifre üretme fonksiyonu


    //Fonskiyon 128 den büyük olmasina izin vermiyor.
    if (boy > 128 ) { boy = 128; }
    if (noalfa > 128) { noalfa = 128; }
    if (noalfa > boy) { noalfa = boy; }


    string passch = System.Web.Security.Membership.GeneratePassword(boy, noalfa);

    //URL encoding ve Url Pass + json sorunu yaratabilecekler pass ediliyor.
    //Microsoft Garanti etmiyor. Alfa Sayisallar Olabiliyorimis . !@#$%^&*()_-+=[{]};:<>|./?.
    //https://msdn.microsoft.com/tr-tr/library/system.web.security.membership.generatepassword(v=vs.110).aspx


    //URL ve Json ajax lar için filtreleme
    passch = passch.Replace(":", "z");
    passch = passch.Replace(";", "W");
    passch = passch.Replace("'", "t");
    passch = passch.Replace("\"", "r");
    passch = passch.Replace("/", "+");
    passch = passch.Replace("\\", "e");

    passch = passch.Replace("?", "9");
    passch = passch.Replace("&", "8");
    passch = passch.Replace("#", "D");
    passch = passch.Replace("%", "u");
    passch = passch.Replace("=", "4");
    passch = passch.Replace("~", "1");

    passch = passch.Replace("[", "2");
    passch = passch.Replace("]", "3");
    passch = passch.Replace("{", "g");
    passch = passch.Replace("}", "J");


    //passch = passch.Replace("(", "6");
    //passch = passch.Replace(")", "0");
    //passch = passch.Replace("|", "p");
    //passch = passch.Replace("@", "4");
    //passch = passch.Replace("!", "u");
    //passch = passch.Replace("$", "Z");
    //passch = passch.Replace("*", "5");
    //passch = passch.Replace("_", "a");

    passch = passch.Replace(",", "V");
    passch = passch.Replace(".", "N");
    passch = passch.Replace("+", "w");
    passch = passch.Replace("-", "7");





    return passch;



}

Check that a input to UITextField is numeric only

This answer uses NSFormatter as said previously. Check it out:

@interface NSString (NSNumber)
- (BOOL) isNumberWithLocale:(NSLocale *) stringLocale;  
- (BOOL) isNumber;
- (NSNumber *) getNumber; 
- (NSNumber *) getNumberWithLocale:(NSLocale*) stringLocale;
@end

@implementation NSString (NSNumber)
- (BOOL) isNumberWithLocale:(NSLocale *) stringLocale
{
    return [self getNumberWithLocale:stringLocale] != nil;
}
- (BOOL) isNumber
{
    return [ self getNumber ] != nil;
}
- (NSNumber *) getNumber
{
    NSLocale *l_en = [[NSLocale alloc] initWithLocaleIdentifier: @"en_US"] ;  
    return [self getNumberWithLocale: [l_en autorelease] ];
}

- (NSNumber *) getNumberWithLocale:(NSLocale*) stringLocale
{
    NSNumberFormatter *formatter = [[ [ NSNumberFormatter alloc ] init ] autorelease];
    [formatter setLocale: stringLocale ];
    return [ formatter numberFromString:self ]; 
}
@end

I hope it helps someone. =)

How to use: while not in

The expression ('AND' and 'OR' and 'NOT') evaluates to 'NOT', so you are testing whether the list has NOT or not.

Shadow Effect for a Text in Android?

Perhaps you'd consider using android:shadowColor, android:shadowDx, android:shadowDy, android:shadowRadius; alternatively setShadowLayer() ?

How do I print debug messages in the Google Chrome JavaScript Console?

Just a quick warning - if you want to test in Internet Explorer without removing all console.log()'s, you'll need to use Firebug Lite or you'll get some not particularly friendly errors.

(Or create your own console.log() which just returns false.)

The provider is not compatible with the version of Oracle client

It would seem to me that though you have ODP with the Oracle Istant Client, the ODP may be trying to use the actual Oracle Client instead. Do you have a standard Oracle client installed on the machine as well? I recall Oracle being quite picky about when it came to multiple clients on the same machine.

Add vertical whitespace using Twitter Bootstrap?

My trick. Not elegant, but it works:

<p>&nbsp;</p>

Untrack files from git temporarily

Use following command to untrack files

git rm --cached <file path>

How to get RegistrationID using GCM in android

Use this code to get Registration ID using GCM

String regId = "", msg = "";

public void getRegisterationID() {

    new AsyncTask() {
        @Override
        protected Object doInBackground(Object...params) {

            String msg = "";
            try {
                if (gcm == null) {
                    gcm = GoogleCloudMessaging.getInstance(Login.this);
                }
                regId = gcm.register(YOUR_SENDER_ID);
                Log.d("in async task", regId);

                // try
                msg = "Device registered, registration ID=" + regId;

            } catch (IOException ex) {
                msg = "Error :" + ex.getMessage();
            }
            return msg;
        }
    }.execute(null, null, null);
 }

and don't forget to write permissions in manifest...
I hope it helps!

Limit Decimal Places in Android EditText

The InputFilter I came up with allows you to configure the number of digits before and after the decimal place. Additionally, it disallows leading zeroes.

public class DecimalDigitsInputFilter implements InputFilter
{
    Pattern pattern;

    public DecimalDigitsInputFilter(int digitsBeforeDecimal, int digitsAfterDecimal)
    {
        pattern = Pattern.compile("(([1-9]{1}[0-9]{0," + (digitsBeforeDecimal - 1) + "})?||[0]{1})((\\.[0-9]{0," + digitsAfterDecimal + "})?)||(\\.)?");
    }

    @Override public CharSequence filter(CharSequence source, int sourceStart, int sourceEnd, Spanned destination, int destinationStart, int destinationEnd)
    {
        // Remove the string out of destination that is to be replaced.
        String newString = destination.toString().substring(0, destinationStart) + destination.toString().substring(destinationEnd, destination.toString().length());

        // Add the new string in.
        newString = newString.substring(0, destinationStart) + source.toString() + newString.substring(destinationStart, newString.length());

        // Now check if the new string is valid.
        Matcher matcher = pattern.matcher(newString);

        if(matcher.matches())
        {
            // Returning null indicates that the input is valid.
            return null;
        }

        // Returning the empty string indicates the input is invalid.
        return "";
    }
}

// To use this InputFilter, attach it to your EditText like so:
final EditText editText = (EditText) findViewById(R.id.editText);

EditText.setFilters(new InputFilter[]{new DecimalDigitsInputFilter(4, 4)});

How to open the Chrome Developer Tools in a new window?

You have to click and hold until the other icon shows up, then slide the mouse down to the icon.

CORS: Cannot use wildcard in Access-Control-Allow-Origin when credentials flag is true

This works for me in development but I can't advise that in production, it's just a different way of getting the job done that hasn't been mentioned yet but probably not the best. Anyway here goes:

You can get the origin from the request, then use that in the response header. Here's how it looks in express:

app.use(function(req, res, next) {
  res.header('Access-Control-Allow-Origin', req.header('origin') );
  next();
});

I don't know what that would look like with your python setup but that should be easy to translate.

Ruby: Merging variables in to a string

The idiomatic way is to write something like this:

"The #{animal} #{action} the #{second_animal}"

Note the double quotes (") surrounding the string: this is the trigger for Ruby to use its built-in placeholder substitution. You cannot replace them with single quotes (') or the string will be kept as is.

How to make background of table cell transparent

You can use the CSS property "background-color: transparent;", or use apha on rgba color representation. Example: "background-color: rgba(216,240,218,0);"

The apha is the last value. It is a decimal number that goes from 0 (totally transparent) to 1 (totally visible).

Angular-Material DateTime Picker Component?

For as long as there is no official date and time picker from angular itself, I would advise to make a combination of the default angular date picker and this Angular Material Timepicker. I've chosen that one because all the other ones I found at this time lack support for issues, are outdated or are not functioning well in the most recent angular versions. This guy seems to be very responsive.

I've wrapped them both in one component so that it looks like it is one unit. You just have to make sure to do a few things:

When no input has been given yet, I would advise:

  • On-click of the component, the datepicker should always be triggered first.
  • After the datepicker closes, have the timepicker automatically popup.
  • Use touchUi = true on the datepicker, so that both the datepicker and the timepicker come as a dialog after each other.
  • Make sure the datepicker also shows up when clicking on the form (instead of only on the icon which is the default).
  • Use this solution to use the timepicker also in a material form, when placing them behind each other, it looks like it is one form.

After a value has been given, it is clear that one part contains the time and the other part contains the date. At that moment it is clear that the user has to click on the time to change the time, and on the date to change the date. But before that, so when both fields are empty (and 'attached' to each other as one field) you should make sure the user cannot be confused by doing above recommendations.

My component is not complete yet, I will try to remember myself to share the code later. Shoot a comment if this question is more then a month old or so.

Edit: Result

enter image description here

<div fxLayout="row">
  <div *ngIf="!dateOnly" [formGroup]="timeFormGroup">
    <mat-form-field>
      <input matInput [ngxTimepicker]="endTime" [format]="24"  placeholder="{{placeholderTime}}" formControlName="endTime" />
    </mat-form-field>
    <ngx-material-timepicker #endTime (timeSet)="timeChange($event)" [minutesGap]="10"></ngx-material-timepicker>
  </div>
  <div>
    <mat-form-field>
      <input id="pickerId" matInput [matDatepicker]="datepicker" placeholder="{{placeholderDate}}" [formControl]="dateForm"
             [min]="config.minDate" [max]="config.maxDate" (dateChange)="dateChange($event)">
      <mat-datepicker-toggle matSuffix [for]="datepicker"></mat-datepicker-toggle>
      <mat-datepicker #datepicker [disabled]="disabled" [touchUi]="config.touchUi" startView="{{config.startView}}"></mat-datepicker>
    </mat-form-field>
  </div>
</div>
import { Component, OnInit, Input, EventEmitter, Output } from '@angular/core';
import { FormControl, FormGroup } from '@angular/forms';
import { DateAdapter, MatDatepickerInputEvent } from '@angular/material';

import * as moment_ from 'moment';

const moment = moment_;

import { MAT_MOMENT_DATE_ADAPTER_OPTIONS } from '@angular/material-moment-adapter';

class DateConfig {
  startView: 'month' | 'year' | 'multi-year';
  touchUi: boolean;
  minDate: moment_.Moment;
  maxDate: moment_.Moment;
}

@Component({
  selector: 'cb-datetimepicker',
  templateUrl: './cb-datetimepicker.component.html',
  styleUrls: ['./cb-datetimepicker.component.scss'],
})
export class DatetimepickerComponent implements OnInit {

  @Input() disabled: boolean;
  @Input() placeholderDate: string;
  @Input() placeholderTime: string;
  @Input() model: Date;
  @Input() purpose: string;
  @Input() dateOnly: boolean;

  @Output() dateUpdate = new EventEmitter<Date>();

  public pickerId: string = "_" + Math.random().toString(36).substr(2, 9);

  public dateForm: FormControl;
  public timeFormGroup: FormGroup;
  public endTime: FormControl;

  public momentDate: moment_.Moment;
  public config: DateConfig;

  //myGroup: FormGroup;


  constructor(private adapter : DateAdapter<any>) { }

  ngOnInit() {

    this.adapter.setLocale("nl-NL");//todo: configurable
    this.config = new DateConfig();
    if (this.purpose === "birthday") {
      this.config.startView = 'multi-year';
      this.config.maxDate = moment().add('year', -15);
      this.config.minDate = moment().add('year', -90);
      this.dateOnly = true;
    } //add more configurations
    else {
      this.config.startView = 'month';
      this.config.maxDate = moment().add('year', 100);
      this.config.minDate = moment().add('year', -100);
    }


    if (window.screen.width < 767) {
      this.config.touchUi = true;
    }



    if (this.model) {
      var mom = moment(this.model);
      if (mom.isBefore(moment('1900-01-01'))) {
        this.momentDate = moment();
      } else {
        this.momentDate = mom;
      }
    } else {
      this.momentDate = moment();
    }

    this.dateForm = new FormControl(this.momentDate);
    if (this.disabled) {
      this.dateForm.disable();
    }
    this.endTime = new FormControl(this.momentDate.format("HH:mm"));

    this.timeFormGroup = new FormGroup({
      endTime: this.endTime
    });


  }


  public dateChange(date: MatDatepickerInputEvent<any>) {

    if (moment.isMoment(date.value)) {
      this.momentDate = moment(date.value);
      if (this.dateOnly) {
        this.momentDate = this.momentDate.utc(true);
      } 
      var newDate = this.momentDate.toDate();
      this.model = newDate;
      this.dateUpdate.emit(newDate);
    }

    console.log("datechange",date);
  }

  public timeChange(time: string) {

    var splitted = time.split(':');
    var hour = splitted[0];
    var minute = splitted[1];

    console.log("time change", time);
   this.momentDate = this.momentDate.set('hour', parseInt(hour));
    this.momentDate = this.momentDate.set('minute', parseInt(minute));

    var newDate = this.momentDate.toDate();
    this.model = newDate;
    this.dateUpdate.emit(newDate);
  }
}

One important source: https://github.com/Agranom/ngx-material-timepicker/issues/126

I think it still deserves some tweaks, as I think it can work a bit better when I would have more time creating this. Most importantly I tried to solve the UTC issue as well, so all dates should be shown in local time but should be sent to the server in UTC format (or at least saved with the correct timezone added to it).

Close Form Button Event

Apply the below code where you want to make code to exit application.

System.Windows.Forms.Application.Exit( )

How can I view all historical changes to a file in SVN

You could use git-svn to import the repository into a Git repository, then use git log -p filename. This shows each log entry for the file followed by the corresponding diff.

Can we rely on String.isEmpty for checking null condition on a String in Java?

Use StringUtils.isEmpty instead, it will also check for null.

Examples are:

 StringUtils.isEmpty(null)      = true
 StringUtils.isEmpty("")        = true
 StringUtils.isEmpty(" ")       = false
 StringUtils.isEmpty("bob")     = false
 StringUtils.isEmpty("  bob  ") = false

See more on official Documentation on String Utils.

I/O error(socket error): [Errno 111] Connection refused

I'm not exactly sure what's causing this. You can try looking in your socket.py (mine is a different version, so line numbers from the trace don't match, and I'm afraid some other details might not match as well).

Anyway, it seems like a good practice to put your url fetching code in a try: ... except: ... block, and handle this with a short pause and a retry. The URL you're trying to fetch may be down, or too loaded, and that's stuff you'll only be able to handle in with a retry anyway.

How to get a list of all valid IP addresses in a local network?

Try following steps:

  1. Type ipconfig (or ifconfig on Linux) at command prompt. This will give you the IP address of your own machine. For example, your machine's IP address is 192.168.1.6. So your broadcast IP address is 192.168.1.255.
  2. Ping your broadcast IP address ping 192.168.1.255 (may require -b on Linux)
  3. Now type arp -a. You will get the list of all IP addresses on your segment.

Angular 4 - get input value

You can use (keyup) or (change) events, see example below:

in HTML:

<input (keyup)="change($event)">

Or

<input (change)="change($event)">

in Component:

change(event) {console.log(event.target.value);}

How do I find the difference between two values without knowing which is larger?

Just use abs(x - y). This'll return the net difference between the two as a positive value, regardless of which value is larger.

Ordering by specific field value first

This works for me using Postgres 9+:

SELECT *
FROM your_table
ORDER BY name = 'core' DESC, priority DESC

What is a Python egg?

"Egg" is a single-file importable distribution format for Python-related projects.

"The Quick Guide to Python Eggs" notes that "Eggs are to Pythons as Jars are to Java..."

Eggs actually are richer than jars; they hold interesting metadata such as licensing details, release dependencies, etc.

How to copy file from host to container using Dockerfile

If you want to copy the current dir's contents, you can run:

docker build  -t <imagename:tag> -f- ./ < Dockerfile

Meaning of delta or epsilon argument of assertEquals for double values

Assert.assertTrue(Math.abs(actual-expected) == 0)

How do I change the text of a span element using JavaScript?

For modern browsers you should use:

document.getElementById("myspan").textContent="newtext";

While older browsers may not know textContent, it is not recommended to use innerHTML as it introduces an XSS vulnerability when the new text is user input (see other answers below for a more detailed discussion):

//POSSIBLY INSECURE IF NEWTEXT BECOMES A VARIABLE!!
document.getElementById("myspan").innerHTML="newtext";

CSS - Make divs align horizontally

You may put an inner div in the container that is enough wide to hold all the floated divs.

_x000D_
_x000D_
#container {_x000D_
  background-color: red;_x000D_
  overflow: hidden;_x000D_
  width: 200px;_x000D_
}_x000D_
_x000D_
#inner {_x000D_
  overflow: hidden;_x000D_
  width: 2000px;_x000D_
}_x000D_
_x000D_
.child {_x000D_
  float: left;_x000D_
  background-color: blue;_x000D_
  width: 50px;_x000D_
  height: 50px;_x000D_
}
_x000D_
<div id="container">_x000D_
  <div id="inner">_x000D_
    <div class="child"></div>_x000D_
    <div class="child"></div>_x000D_
    <div class="child"></div>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Overriding interface property type defined in Typescript d.ts file

Omit the property when extending the interface:

interface A {
  a: number;
  b: number;
}

interface B extends Omit<A, 'a'> {
  a: boolean;
}

Failed to resolve: com.google.android.gms:play-services in IntelliJ Idea with gradle

I tried solving this problem for hours after I haven't used Android Studio some time and wasn't aware of the updates.

It is important that google() is the first item that stands in repositories like this:

allprojects {
    repositories {
        google()
        jcenter()
        mavenCentral()
    }
}

Somehow google() was the second item after jcenter(), so everything was messed up and didn't work. Maybe this helps someone.

What can cause a “Resource temporarily unavailable” on sock send() command

Let'e me give an example:

  1. client connect to server, and send 1MB data to server every 1 second.

  2. server side accept a connection, and then sleep 20 second, without recv msg from client.So the tcp send buffer in the client side will be full.

Code in client side:

#include <arpa/inet.h>
#include <sys/socket.h>
#include <stdio.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#define exit_if(r, ...)                                                                          \
    if (r) {                                                                                     \
        printf(__VA_ARGS__);                                                                     \
        printf("%s:%d error no: %d error msg %s\n", __FILE__, __LINE__, errno, strerror(errno)); \
        exit(1);                                                                                 \
    }

void setNonBlock(int fd) {
    int flags = fcntl(fd, F_GETFL, 0);
    exit_if(flags < 0, "fcntl failed");
    int r = fcntl(fd, F_SETFL, flags | O_NONBLOCK);
    exit_if(r < 0, "fcntl failed");
}

void test_full_sock_buf_1(){
    short port = 8000;
    struct sockaddr_in addr;
    memset(&addr, 0, sizeof addr);
    addr.sin_family = AF_INET;
    addr.sin_port = htons(port);
    addr.sin_addr.s_addr = INADDR_ANY;


    int fd = socket(AF_INET, SOCK_STREAM, 0);
    exit_if(fd<0, "create socket error");

    int ret = connect(fd, (struct sockaddr *) &addr, sizeof(struct sockaddr));
    exit_if(ret<0, "connect to server error");
    setNonBlock(fd);

    printf("connect to server success");

    const int LEN = 1024 * 1000;
    char msg[LEN];  // 1MB data
    memset(msg, 'a', LEN);

    for (int i = 0; i < 1000; ++i) {
        int len = send(fd, msg, LEN, 0);
        printf("send: %d, erron: %d, %s \n", len, errno, strerror(errno));
        sleep(1);
    }

}

int main(){
    test_full_sock_buf_1();

    return 0;
}

Code in server side:

    #include <arpa/inet.h>
    #include <sys/socket.h>
    #include <stdio.h>
    #include <errno.h>
    #include <fcntl.h>
    #include <stdlib.h>
    #include <string.h>
    #define exit_if(r, ...)                                                                          \
        if (r) {                                                                                     \
            printf(__VA_ARGS__);                                                                     \
            printf("%s:%d error no: %d error msg %s\n", __FILE__, __LINE__, errno, strerror(errno)); \
            exit(1);                                                                                 \
        }
void test_full_sock_buf_1(){

    int listenfd = socket(AF_INET, SOCK_STREAM, 0);
    exit_if(listenfd<0, "create socket error");

    short port = 8000;
    struct sockaddr_in addr;
    memset(&addr, 0, sizeof addr);
    addr.sin_family = AF_INET;
    addr.sin_port = htons(port);
    addr.sin_addr.s_addr = INADDR_ANY;

    int r = ::bind(listenfd, (struct sockaddr *) &addr, sizeof(struct sockaddr));
    exit_if(r<0, "bind socket error");

    r = listen(listenfd, 100);
    exit_if(r<0, "listen socket error");

    struct sockaddr_in raddr;
    socklen_t rsz = sizeof(raddr);
    int cfd = accept(listenfd, (struct sockaddr *) &raddr, &rsz);
    exit_if(cfd<0, "accept socket error");

    sockaddr_in peer;
    socklen_t alen = sizeof(peer);
    getpeername(cfd, (sockaddr *) &peer, &alen);

    printf("accept a connection from %s:%d\n", inet_ntoa(peer.sin_addr), ntohs(peer.sin_port));

    printf("but now I will sleep 15 second, then exit");
    sleep(15);
}

Start server side, then start client side.

server side may output:

accept a connection from 127.0.0.1:35764
but now I will sleep 15 second, then exit
Process finished with exit code 0

enter image description here

client side may output:

connect to server successsend: 1024000, erron: 0, Success 
send: 1024000, erron: 0, Success 
send: 1024000, erron: 0, Success 
send: 552190, erron: 0, Success 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 11, Resource temporarily unavailable 
send: -1, erron: 104, Connection reset by peer 
send: -1, erron: 32, Broken pipe 
send: -1, erron: 32, Broken pipe 
send: -1, erron: 32, Broken pipe 
send: -1, erron: 32, Broken pipe 
send: -1, erron: 32, Broken pipe 

enter image description here

You can see, as the server side doesn't recv the data from client, so when the client side tcp buffer get full, but you still send data, so you may get Resource temporarily unavailable error.

jQuery - Getting form values for ajax POST

try as this code.

$.ajax({
        type: "POST",
        url: "http://rt.ja.com/includes/register.php?submit=1",
        data: "username="+username+"&email="+email+"&password="+password+"&passconf="+passconf,

        success: function(html)
        {   
            //alert(html);
            $('#userError').html(html);
            $("#userError").html(userChar);
            $("#userError").html(userTaken);
        }
    });

i think this will work definitely..

you can also use .serialize() function for sending data via jquery Ajax..

i.e: data : $("#registerSubmit").serialize()

Thanks.

MySQL error 2006: mysql server has gone away

uncomment the ligne below in your my.ini/my.cnf, this will split your large file into smaller portion

# binary logging format - mixed recommended
# binlog_format=mixed

TO

# binary logging format - mixed recommended
binlog_format=mixed

How can I create C header files

  1. Open your favorite text editor
  2. Create a new file named whatever.h
  3. Put your function prototypes in it

DONE.

Example whatever.h

#ifndef WHATEVER_H_INCLUDED
#define WHATEVER_H_INCLUDED
int f(int a);
#endif

Note: include guards (preprocessor commands) added thanks to luke. They avoid including the same header file twice in the same compilation. Another possibility (also mentioned on the comments) is to add #pragma once but it is not guaranteed to be supported on every compiler.

Example whatever.c

#include "whatever.h"

int f(int a) { return a + 1; }

And then you can include "whatever.h" into any other .c file, and link it with whatever.c's object file.

Like this:

sample.c

#include "whatever.h"

int main(int argc, char **argv)
{
    printf("%d\n", f(2)); /* prints 3 */
    return 0;
}

To compile it (if you use GCC):

$ gcc -c whatever.c -o whatever.o
$ gcc -c sample.c -o sample.o

To link the files to create an executable file:

$ gcc sample.o whatever.o -o sample

You can test sample:

$ ./sample
3
$

Extract substring from a string

Here is a real world example:

String hallostring = "hallo";
String asubstring = hallostring.substring(0, 1); 

In the example asubstring would return: h

What is the purpose and use of **kwargs?

On the basis that a good sample is sometimes better than a long discourse I will write two functions using all python variable argument passing facilities (both positional and named arguments). You should easily be able to see what it does by yourself:

def f(a = 0, *args, **kwargs):
    print("Received by f(a, *args, **kwargs)")
    print("=> f(a=%s, args=%s, kwargs=%s" % (a, args, kwargs))
    print("Calling g(10, 11, 12, *args, d = 13, e = 14, **kwargs)")
    g(10, 11, 12, *args, d = 13, e = 14, **kwargs)

def g(f, g = 0, *args, **kwargs):
    print("Received by g(f, g = 0, *args, **kwargs)")
    print("=> g(f=%s, g=%s, args=%s, kwargs=%s)" % (f, g, args, kwargs))

print("Calling f(1, 2, 3, 4, b = 5, c = 6)")
f(1, 2, 3, 4, b = 5, c = 6)

And here is the output:

Calling f(1, 2, 3, 4, b = 5, c = 6)
Received by f(a, *args, **kwargs) 
=> f(a=1, args=(2, 3, 4), kwargs={'c': 6, 'b': 5}
Calling g(10, 11, 12, *args, d = 13, e = 14, **kwargs)
Received by g(f, g = 0, *args, **kwargs)
=> g(f=10, g=11, args=(12, 2, 3, 4), kwargs={'c': 6, 'b': 5, 'e': 14, 'd': 13})

What's wrong with nullable columns in composite primary keys?

I still believe this is a fundamental / functional flaw brought about by a technicality. If you have an optional field by which you can identify a customer you now have to hack a dummy value into it, just because NULL != NULL, not particularly elegant yet it is an "industry standard"

Nginx: Job for nginx.service failed because the control process exited

For my case, I need to run

sudo nginx -t

It will check if Nginx configuration is correct or not, if not, it will show you which configuration causes the error.

Then you need to go to /etc/nginx/sites-available to fix the broken configuration.

After that, you can restart Nginx without any problem.

sudo systemctl restart nginx

jQuery set checkbox checked

Dude try below code :

$("div.row-form input[type='checkbox']").attr('checked','checked')

OR

$("div.row-form #estado_cat").attr("checked","checked");

OR

$("div.row-form #estado_cat").attr("checked",true);

Error 1053 the service did not respond to the start or control request in a timely fashion

I know this is old question, I used to write my own VB.NET windows service, and it has no issue to start on MS windows 7 and MS windows 10.

I have this issue when I install the windows services on latest MS windows 10 patch. The reason the windows service doesn't run it is because the .NET version that needed for the window services to run is not presented in the installed PC.

After you have installed the windows services. go to the install folder for example C:\Program files (x86)\Service1\Service1.exe and double click to run it. If there is missing .NET framework package, it will prompt the user to download it. Just download and and wait for it to install.

After that restart the windows services in services.msc. Hope this answer will help someone who face the issue. I know issue is caused by .NET framework version.

How to find row number of a value in R code

(1:nrow(mydata_2))[mydata_2[,4] == 1578]

Of course there may be more than one row with a value of 1578.

How do I preserve line breaks when getting text from a textarea?

I suppose you don't want your textarea-content to be parsed as HTML. In this case, you can just set it as plaintext so the browser doesn't treat it as HTML and doesn't remove newlines No CSS or preprocessing required.

_x000D_
_x000D_
<script>_x000D_
function copycontent(){_x000D_
 var content = document.getElementById('ta').value;_x000D_
 document.getElementById('target').innerText = content;_x000D_
}_x000D_
</script>_x000D_
<textarea id='ta' rows='3'>_x000D_
  line 1_x000D_
  line 2_x000D_
  line 3_x000D_
</textarea>_x000D_
<button id='btn' onclick='copycontent();'>_x000D_
Copy_x000D_
</button>_x000D_
<p id='target'></p>
_x000D_
_x000D_
_x000D_

Django Cookies, how can I set them?

Using Django's session framework should cover most scenarios, but Django also now provide direct cookie manipulation methods on the request and response objects (so you don't need a helper function).

Setting a cookie:

def view(request):
  response = HttpResponse('blah')
  response.set_cookie('cookie_name', 'cookie_value')

Retrieving a cookie:

def view(request):
  value = request.COOKIES.get('cookie_name')
  if value is None:
    # Cookie is not set

  # OR

  try:
    value = request.COOKIES['cookie_name']
  except KeyError:
    # Cookie is not set

Why are the Level.FINE logging messages not showing?

why is my java logging not working

provides a jar file that will help you work out why your logging in not working as expected. It gives you a complete dump of what loggers and handlers have been installed and what levels are set and at which level in the logging hierarchy.

How can I use the python HTMLParser library to extract data from a specific div tag?

class LinksParser(HTMLParser.HTMLParser):
  def __init__(self):
    HTMLParser.HTMLParser.__init__(self)
    self.recording = 0
    self.data = []

  def handle_starttag(self, tag, attributes):
    if tag != 'div':
      return
    if self.recording:
      self.recording += 1
      return
    for name, value in attributes:
      if name == 'id' and value == 'remository':
        break
    else:
      return
    self.recording = 1

  def handle_endtag(self, tag):
    if tag == 'div' and self.recording:
      self.recording -= 1

  def handle_data(self, data):
    if self.recording:
      self.data.append(data)

self.recording counts the number of nested div tags starting from a "triggering" one. When we're in the sub-tree rooted in a triggering tag, we accumulate the data in self.data.

The data at the end of the parse are left in self.data (a list of strings, possibly empty if no triggering tag was met). Your code from outside the class can access the list directly from the instance at the end of the parse, or you can add appropriate accessor methods for the purpose, depending on what exactly is your goal.

The class could be easily made a bit more general by using, in lieu of the constant literal strings seen in the code above, 'div', 'id', and 'remository', instance attributes self.tag, self.attname and self.attvalue, set by __init__ from arguments passed to it -- I avoided that cheap generalization step in the code above to avoid obscuring the core points (keep track of a count of nested tags and accumulate data into a list when the recording state is active).

Defining TypeScript callback type

To go one step further, you could declare a type pointer to a function signature like:

interface myCallbackType { (myArgument: string): void }

and use it like this:

public myCallback : myCallbackType;

Enable & Disable a Div and its elements in Javascript

The following selects all descendant elements and disables them:

$("#dcacl").find("*").prop("disabled", true);

But it only really makes sense to disable certain element types: inputs, buttons, etc., so you want a more specific selector:

$("#dcac1").find(":input").prop("disabled",true);
// noting that ":input" gives you the equivalent of
$("#dcac1").find("input,select,textarea,button").prop("disabled",true);

To re-enable you just set "disabled" to false.

I want to Disable them at loading the page and then by a click i can enable them

OK, so put the above code in a document ready handler, and setup an appropriate click handler:

$(document).ready(function() {
    var $dcac1kids = $("#dcac1").find(":input");
    $dcac1kids.prop("disabled",true);

    // not sure what you want to click on to re-enable
    $("selector for whatever you want to click").one("click",function() {
       $dcac1kids.prop("disabled",false);
    }
}

I've cached the results of the selector on the assumption that you're not adding more elements to the div between the page load and the click. And I've attached the click handler with .one() since you haven't specified a requirement to re-disable the elements so presumably the event only needs to be handled once. Of course you can change the .one() to .click() if appropriate.

MVC 4 - Return error message from Controller - Show in View

The Return View(model) returns you error because you don't fill the model with the values in your post method and the model data for the dropdown is empty. Please provide the Get method to explain further how to manage displaying the error. In order to the error to be shown you should use this:

[HttpPost]
public ActionResult form_edit(FormModels model)
{          
   if(ModelState.IsValid())
   {
      --- operations 
      return Redirect("OtherAction", "SomeController");
   }

   // here you can use a little trick
   //fill the model property that holds the information for the dropdown with the data 

   // you haven't provided the get method but it should look something like this
   model.Countries = ... some data goes here;
   model.dd_value = ... some other data;
   model.dd_text = ... other data;

   ModelState.AddModelError("", "adfdghdghgdhgdhdgda");
   return View(model);
}

and then in the view just use :

@model mvc_cs.Models.FormModels
@using ctrlr = mvc_cs.Controllers.FormController


@using (Html.BeginForm("form_edit", "Form", FormMethod.Post))
{

    <table>
    <tr>
    <td>       
    @Html.ValidationSummary(true)             
    </td>
    </tr>
<tr>
    <th>
        @Html.DisplayNameFor(model => model.content_name)
        @Html.DropDownListFor(x => x.selectedvalue, new SelectList(Model.Countries, Model.dd_value, Model.dd_text), "-- Select Product--")

    </th>
</tr>
</table>

<table>
<tr>
    <td>
        <input  type="submit" value="Submit" />
    </td>
</tr>
</table>
}

This should work okay.

If you just use RedirectToAction it will redirect you to the get method --> you will have no error but the view will be just reloaded and no error would be shown.

other way around is that you can pass the error not by ModelState.AddError, but with ViewData["error"] like this:

[HttpPost]
public ActionResult form_edit(FormModels model)
{          
   TempData["error"] = "someErrorMessage";
   return RedirectToAction("form_Post", "Form");
}

[HttpGet]
public ActionResult form_edit()
{
    do stuff here ----
    ViewData["error"] = TempData["error"];
    return View();
}

@model mvc_cs.Models.FormModels
@using ctrlr = mvc_cs.Controllers.FormController


@using (Html.BeginForm("form_edit", "Form", FormMethod.Post))
{

    <table>
    <tr>
    <td>       
    <div>@ViewData["error"]</div>             
    </td>
    </tr>
<tr>
    <th>
        @Html.DisplayNameFor(model => model.content_name)
        @Html.DropDownListFor(x => x.selectedvalue, new SelectList(Model.Countries, Model.dd_value, Model.dd_text), "-- Select Product--")

    </th>
</tr>
</table>

<table>
<tr>
    <td>
        <input  type="submit" value="Submit" />
    </td>
</tr>
</table>
}

Adding items to an object through the .push() method

Another way of doing it would be:

stuff = Object.assign(stuff, {$(this).attr('value'):$(this).attr('checked')});

Read more here: Object.assign()

must appear in the GROUP BY clause or be used in an aggregate function

SELECT t1.cname, t1.wmname, t2.max
FROM makerar t1 JOIN (
    SELECT cname, MAX(avg) max
    FROM makerar
    GROUP BY cname ) t2
ON t1.cname = t2.cname AND t1.avg = t2.max;

Using rank() window function:

SELECT cname, wmname, avg
FROM (
    SELECT cname, wmname, avg, rank() 
    OVER (PARTITION BY cname ORDER BY avg DESC)
    FROM makerar) t
WHERE rank = 1;

Note

Either one will preserve multiple max values per group. If you want only single record per group even if there is more than one record with avg equal to max you should check @ypercube's answer.

Insert data into a view (SQL Server)

Go to design for that table. Now, on the right, set the ID column as the column in question. It will now auto populate without specification.

How to get to Model or Viewbag Variables in a Script Tag

Use single quotation marks ('):

var val = '@ViewBag.ForSection';
alert(val);

Twitter Bootstrap onclick event on buttons-radio

I needed to do the same thing for a chart where you could select the period of the data that should be displayed.

Therefore I introduced the CSS class 'btn-group-radio' and used the following unobtrusive javascript one-liner:

// application.js
$(document).ready(function() {
  $('.btn-group-radio .btn').click(function() {
    $(this).addClass('active').siblings('.btn').removeClass('active');
  });
});

And here is the HTML:

<!-- some arbitrary view -->
<div class="btn-group btn-group-radio">
  <%= link_to '1W', charts_path('1W'), class: 'btn btn-default active', remote: true %>
  <%= link_to '1M', charts_path('1M'), class: 'btn btn-default', remote: true %>
  <%= link_to '3M', charts_path('3M'), class: 'btn btn-default', remote: true %>
  <%= link_to '6M', charts_path('6M'), class: 'btn btn-default', remote: true %>
  <%= link_to '1Y', charts_path('1Y'), class: 'btn btn-default', remote: true %>
  <%= link_to 'All', charts_path('all'), class: 'btn btn-default', remote: true %>
</div>

How to pass in a react component into another react component to transclude the first component's content?

You can pass in a component via. the props and render it with interpolation.

var DivWrapper = React.createClass({
    render: function() {
        return <div>{ this.props.child }</div>;
    }
});

You would then pass in a prop called child, which would be a React component.

What are the git concepts of HEAD, master, origin?

I highly recommend the book "Pro Git" by Scott Chacon. Take time and really read it, while exploring an actual git repo as you do.

HEAD: the current commit your repo is on. Most of the time HEAD points to the latest commit in your current branch, but that doesn't have to be the case. HEAD really just means "what is my repo currently pointing at".

In the event that the commit HEAD refers to is not the tip of any branch, this is called a "detached head".

master: the name of the default branch that git creates for you when first creating a repo. In most cases, "master" means "the main branch". Most shops have everyone pushing to master, and master is considered the definitive view of the repo. But it's also common for release branches to be made off of master for releasing. Your local repo has its own master branch, that almost always follows the master of a remote repo.

origin: the default name that git gives to your main remote repo. Your box has its own repo, and you most likely push out to some remote repo that you and all your coworkers push to. That remote repo is almost always called origin, but it doesn't have to be.

HEAD is an official notion in git. HEAD always has a well-defined meaning. master and origin are common names usually used in git, but they don't have to be.

Move / Copy File Operations in Java

Previous answers seem to be outdated.

Java's File.renameTo() is probably the easiest solution for API 7, and seems to work fine. Be carefull IT DOES NOT THROW EXCEPTIONS, but returns true/false!!!

Note that there seem to be problems with it in previous versions (same as NIO).

If you need to use a previous version, check here.

Here's an example for API7:

File f1= new File("C:\\Users\\.....\\foo");
File f2= new File("C:\\Users\\......\\foo.old");
System.err.println("Result of move:"+f1.renameTo(f2));

Alternatively:

System.err.println("Move:" +f1.toURI() +"--->>>>"+f2.toURI());
Path b1=Files.move(f1.toPath(),  f2.toPath(), StandardCopyOption.ATOMIC_MOVE ,StandardCopyOption.REPLACE_EXISTING ););
System.err.println("Move: RETURNS:"+b1);

Could not connect to SMTP host: smtp.gmail.com, port: 465, response: -1

What i did was i commented out the

props.put("mail.smtp.starttls.enable","true"); 

Because apparently for G-mail you did not need it. Then if you haven't already done this you need to create an app password in G-mail for your program. I did that and it worked perfectly. Here this link will show you how: https://support.google.com/accounts/answer/185833.

How do I make Git ignore file mode (chmod) changes?

If you want to set this option for all of your repos, use the --global option.

git config --global core.filemode false

If this does not work you are probably using a newer version of git so try the --add option.

git config --add --global core.filemode false

If you run it without the --global option and your working directory is not a repo, you'll get

error: could not lock config file .git/config: No such file or directory

Get CPU Usage from Windows Command Prompt

The following works correctly on Windows 7 Ultimate from an elevated command prompt:

C:\Windows\system32>typeperf "\Processor(_Total)\% Processor Time"

"(PDH-CSV 4.0)","\\vm\Processor(_Total)\% Processor Time"
"02/01/2012 14:10:59.361","0.648721"
"02/01/2012 14:11:00.362","2.986384"
"02/01/2012 14:11:01.364","0.000000"
"02/01/2012 14:11:02.366","0.000000"
"02/01/2012 14:11:03.367","1.038332"

The command completed successfully.

C:\Windows\system32>

Or for a snapshot:

C:\Windows\system32>wmic cpu get loadpercentage
LoadPercentage
8

PHP Header redirect not working

COMMON PROBLEMS:

1) There should be NO output (i.e. echo... or HTML parts) before the header(...); command.

2) After header(...); you must use exit();

3) Remove any white-space(or newline) before <?php and after ?> tags.

4) Check that php file (and also other .php files, that are included) - they should have UTF8 without BOM encoding (and not just UTF-8). Because default UTF8 adds invisible character in the start of file (called "BOM"), so you should avoid that !!!!!!!!!!!

5) Use 301 or 302 reference:

header("location: http://example.com",  true,  301 );  exit;

6) Turn on error reporting. And tell the error.

7) If none of above helps, use JAVASCRIPT redirection (however, discouraged method), may be the last chance in custom cases...:

echo "<script type='text/javascript'>window.top.location='http://website.com/';</script>"; exit;

Failed to load c++ bson extension

Here's how I fixed the problem on Ubuntu:

  1. ln -s /usr/bin/nodejs /usr/bin/node
  2. npm install node-gyp
  3. cd node_modules/mongodb/node_modules/bson
  4. node-gyp rebuild

Inspired by @mbochynski answer, but I had to create a symbolic link first, otherwise the rebuild failed.

What's the difference between HEAD, working tree and index, in Git?

Your working tree is what is actually in the files that you are currently working on.

HEAD is a pointer to the branch or commit that you last checked out, and which will be the parent of a new commit if you make it. For instance, if you're on the master branch, then HEAD will point to master, and when you commit, that new commit will be a descendent of the revision that master pointed to, and master will be updated to point to the new commit.

The index is a staging area where the new commit is prepared. Essentially, the contents of the index are what will go into the new commit (though if you do git commit -a, this will automatically add all changes to files that Git knows about to the index before committing, so it will commit the current contents of your working tree). git add will add or update files from the working tree into your index.

jQuery javascript regex Replace <br> with \n

a cheap and nasty would be:

jQuery("#myDiv").html().replace("<br>", "\n").replace("<br />", "\n")

EDIT

jQuery("#myTextArea").val(
    jQuery("#myDiv").html()
        .replace(/\<br\>/g, "\n")
        .replace(/\<br \/\>/g, "\n")
);

Also created a jsfiddle if needed: http://jsfiddle.net/2D3xx/

How to compare dates in c#

Firstly, understand that DateTime objects aren't formatted. They just store the Year, Month, Day, Hour, Minute, Second, etc as a numeric value and the formatting occurs when you want to represent it as a string somehow. You can compare DateTime objects without formatting them.

To compare an input date with DateTime.Now, you need to first parse the input into a date and then compare just the Year/Month/Day portions:

DateTime inputDate;
if(!DateTime.TryParse(inputString, out inputDate))
    throw new ArgumentException("Input string not in the correct format.");

if(inputDate.Date == DateTime.Now.Date) {
    // Same date!
}

Convert YYYYMMDD string date to a datetime value

You should have to use DateTime.TryParseExact.

var newDate = DateTime.ParseExact("20111120", 
                                  "yyyyMMdd", 
                                   CultureInfo.InvariantCulture);

OR

string str = "20111021";
string[] format = {"yyyyMMdd"};
DateTime date;

if (DateTime.TryParseExact(str, 
                           format, 
                           System.Globalization.CultureInfo.InvariantCulture,
                           System.Globalization.DateTimeStyles.None, 
                           out date))
{
     //valid
}

Bootstrap modal - close modal when "call to action" button is clicked

Make as shown.

_x000D_
_x000D_
  $(document).ready(function(){_x000D_
    $('#myModal').modal('show');_x000D_
_x000D_
    $('#myBtn').on('click', function(){_x000D_
      $('#myModal').modal('show');_x000D_
    });_x000D_
    _x000D_
  });_x000D_
<br/>_x000D_
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<!DOCTYPE html>_x000D_
<html lang="en">_x000D_
<head>_x000D_
  <title>Bootstrap Example</title>_x000D_
  <meta charset="utf-8">_x000D_
  <meta name="viewport" content="width=device-width, initial-scale=1">_x000D_
  <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">_x000D_
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
  <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>_x000D_
</head>_x000D_
<body>_x000D_
_x000D_
<div class="container">_x000D_
  <h2>Activate Modal with JavaScript</h2>_x000D_
  <!-- Trigger the modal with a button -->_x000D_
  <button type="button" class="btn btn-info btn-lg" id="myBtn">Open Modal</button>_x000D_
_x000D_
  <!-- Modal -->_x000D_
  <div class="modal fade" id="myModal" role="dialog">_x000D_
    <div class="modal-dialog">_x000D_
    _x000D_
      <!-- Modal content-->_x000D_
      <div class="modal-content">_x000D_
        <div class="modal-header">_x000D_
          <button type="button" class="close" data-dismiss="modal">&times;</button>_x000D_
          <h4 class="modal-title">Modal Header</h4>_x000D_
        </div>_x000D_
        <div class="modal-body">_x000D_
          <p>Some text in the modal.</p>_x000D_
        </div>_x000D_
_x000D_
      </div>_x000D_
      _x000D_
    </div>_x000D_
  </div>_x000D_
  _x000D_
</div>
_x000D_
_x000D_
_x000D_

Set drawable size programmatically

Specify the size with setBounds(), ie for a 50x50 size use

drawable.setBounds(0, 0, 50, 50);

public void setBounds (int left, int top, int right, int bottom)

Convert StreamReader to byte[]

You can also use CopyTo:

var ms = new MemoryStream();
yourStreamReader.BaseStream.CopyTo(ms); // blocking call till the end of the stream
ms.GetBuffer().CopyTo(yourArray, ms.Length);

or

var ms = new MemoryStream();
var ct = yourStreamReader.BaseStream.CopyToAsync(ms);
await ct;
ms.GetBuffer().CopyTo(yourArray, ms.Length);

get current date with 'yyyy-MM-dd' format in Angular 4

you can try doing this.


component.ts

currentDate = new Date();

component.html

{{currentDate | date:'yyyy-MM-dd'}}

Connection string with relative path to the database file

After several strange errors with relative paths in connectionstring I felt the need to post this here.

When using "|DataDirectory|" or "~" you are not allowed to step up and out using "../" !

Example is using several projects accessing the same localdb file placed in one of the projects.

" ~/../other" and " |DataDirectory|/../other" will fail

Even if it is clearly written at MSDN here the errors it gave where a bit unclear so hard to find and could not find it here at SO.

Remote JMX connection

the thing that work for me was to set /etc/hosts to point the hostname to the ip and not to the loopback interface and than restart my application.

cat /etc/hosts

127.0.0.1      localhost.localdomain localhost
192.168.0.1    myservername

This is my configuration:

-Dcom.sun.management.jmxremote.port=1617 
-Dcom.sun.management.jmxremote.ssl=false 
-Dcom.sun.management.jmxremote.authenticate=false

PHP mkdir: Permission denied problem

After you install the ftp server with sudo apt-get install vsftpd you will have to configure it. To enable write access you have to edit the /etc/vsftpd.conf file and uncomment the

#write_enable=YES

line, so it should read

write_enable=YES

Save the file and restart vsftpd with sudo service vsftpd restart.

For other configuration options consult this documentation or man vsftpd.conf

What is the Simplest Way to Reverse an ArrayList?

A little more readable :)

public static <T> ArrayList<T> reverse(ArrayList<T> list) {
    int length = list.size();
    ArrayList<T> result = new ArrayList<T>(length);

    for (int i = length - 1; i >= 0; i--) {
        result.add(list.get(i));
    }

    return result;
}

Eclipse not recognizing JVM 1.8

For some weird reason "Java SE Development Kit 8u151" gives this trouble. Just install, "Java SE Development Kit 8u152" from the following link-

http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

It should work then.

How to copy files across computers using SSH and MAC OS X Terminal

You may also want to look at rsync if you're doing a lot of files.

If you're going to making a lot of changes and want to keep your directories and files in sync, you may want to use a version control system like Subversion or Git. See http://xoa.petdance.com/How_to:_Keep_your_home_directory_in_Subversion

How to move a git repository into another directory and make that directory a git repository?

I am no expert, but I copy the .git folder to a new folder, then invoke: git reset --hard

Linux delete file with size 0

To search and delete empty files in the current directory and subdirectories:

find . -type f -empty -delete

-type f is necessary because also directories are marked to be of size zero.


The dot . (current directory) is the starting search directory. If you have GNU find (e.g. not Mac OS), you can omit it in this case:

find -type f -empty -delete

From GNU find documentation:

If no files to search are specified, the current directory (.) is used.

How to determine if binary tree is balanced?

Bonus exercise response. The simple solution. Obviously in a real implementation one might wrap this or something to avoid requiring the user to include height in their response.

IsHeightBalanced(tree, out height)
    if (tree is empty)
        height = 0
        return true
    balance = IsHeightBalanced(tree.left, heightleft) and IsHeightBalanced(tree.right, heightright)
    height = max(heightleft, heightright)+1
    return balance and abs(heightleft - heightright) <= 1     

How to search through all Git and Mercurial commits in the repository for a certain string?

In Mercurial you use hg log --keyword to search for keywords in the commit messages and hg log --user to search for a particular user. See hg help log for other ways to limit the log.

Pass variables from servlet to jsp

You can also use RequestDispacher and pass on the data along with the jsp page you want.

request.setAttribute("MyData", data);
RequestDispatcher rd = request.getRequestDispatcher("page.jsp");
rd.forward(request, response);

'git status' shows changed files, but 'git diff' doesn't

I suspect there is something wrong either with your Git installation or your repository.

Try running:

GIT_TRACE=2 git <command>

See if you get anything useful. If that doesn't help, just use strace and see what's going wrong:

strace git <command>

Why do we use __init__ in Python classes?

class Dog(object):

    # Class Object Attribute
    species = 'mammal'

    def __init__(self,breed,name):
        self.breed = breed
        self.name = name

In above example we use species as a global since it will be always same(Kind of constant you can say). when you call __init__ method then all the variable inside __init__ will be initiated(eg:breed,name).

class Dog(object):
    a = '12'

    def __init__(self,breed,name,a):
        self.breed = breed
        self.name = name
        self.a= a

if you print the above example by calling below like this

Dog.a
12

Dog('Lab','Sam','10')
Dog.a
10

That means it will be only initialized during object creation. so anything which you want to declare as constant make it as global and anything which changes use __init__

What is the correct way to restore a deleted file from SVN?

You should be able to just check out the one file you want to restore. Try something like svn co svn://your_repos/path/to/file/you/want/to/restore@rev where rev is the last revision at which the file existed.

I had to do exactly this a little while ago and if I remember correctly, using the -r option to svn didn't work; I had to use the :rev syntax. (Although I might have remembered it backwards...)

When to use RDLC over RDL reports?

From my experience, if you need high performance (this does depend slightly on your client specs) on large reports, go with rdlc. Additionally, rdlc reports give you a very full range of control over your data, you may be able to save yourself wasted database trips, etc. by using client side reports. On the project I'm currently working on, a critical report requires about 2 minutes to render on the server side, and pretty much takes out whichever reporting server it hits for that time. Switching it to client side rendering, we see performance much closer to 20-40 seconds with no load on the report server and less bandwidth used because only the datasets are being downloaded.

Your mileage may vary, and I find rdlc's add development and maintenance complexity, especially when your report has been designed as a server side report.

How Does Modulus Divison Work

Easier when your number after the decimal (0.xxx) is short. Then all you need to do is multiply that number with the number after the division.

Ex: 32 % 12 = 8

You do 32/12=2.666666667 Then you throw the 2 away, and focus on the 0.666666667 0.666666667*12=8 <-- That's your answer.

(again, only easy when the number after the decimal is short)

How to crop a CvMat in OpenCV?

To get better results and robustness against differents types of matrices, you can do this in addition to the first answer, that copy the data :

cv::Mat source = getYourSource();

// Setup a rectangle to define your region of interest
cv::Rect myROI(10, 10, 100, 100);

// Crop the full image to that image contained by the rectangle myROI
// Note that this doesn't copy the data
cv::Mat croppedRef(source, myROI);

cv::Mat cropped;
// Copy the data into new matrix
croppedRef.copyTo(cropped);

What is C# analog of C++ std::pair?

I created a C# implementation of Tuples, which solves the problem generically for between two and five values - here's the blog post, which contains a link to the source.

AttributeError: 'tuple' object has no attribute

Variables names are only locally meaningful.

Once you hit

return s1,s2,s3,s4

at the end of the method, Python constructs a tuple with the values of s1, s2, s3 and s4 as its four members at index 0, 1, 2 and 3 - NOT a dictionary of variable names to values, NOT an object with variable names and their values, etc.

If you want the variable names to be meaningful after you hit return in the method, you must create an object or dictionary.

Simplest way to do grouped barplot

There are several ways to do plots in R; lattice is one of them, and always a reasonable solution, +1 to @agstudy. If you want to do this in base graphics, you could try the following:

Reasonstats <- read.table(text="Category         Reason  Species
                                 Decline        Genuine       24
                                Improved        Genuine       16
                                Improved  Misclassified       85
                                 Decline  Misclassified       41
                                 Decline      Taxonomic        2
                                Improved      Taxonomic        7
                                 Decline        Unclear       41
                                Improved        Unclear      117", header=T)

ReasonstatsDec <- Reasonstats[which(Reasonstats$Category=="Decline"),]
ReasonstatsImp <- Reasonstats[which(Reasonstats$Category=="Improved"),]
Reasonstats3   <- cbind(ReasonstatsImp[,3], ReasonstatsDec[,3])
colnames(Reasonstats3) <- c("Improved", "Decline")
rownames(Reasonstats3) <- ReasonstatsImp$Reason

windows()
  barplot(t(Reasonstats3), beside=TRUE, ylab="number of species", 
          cex.names=0.8, las=2, ylim=c(0,120), col=c("darkblue","red"))
  box(bty="l")

enter image description here

Here's what I did: I created a matrix with two columns (because your data were in columns) where the columns were the species counts for Decline and for Improved. Then I made those categories the column names. I also made the Reasons the row names. The barplot() function can operate over this matrix, but wants the data in rows rather than columns, so I fed it a transposed version of the matrix. Lastly, I deleted some of your arguments to your barplot() function call that were no longer needed. In other words, the problem was that your data weren't set up the way barplot() wants for your intended output.

Start script missing error when running npm start

I had this issue while installing react-js for the first time : These line helped me solve the issue:

npm rm -g create-react-app
npm install -g create-react-app
npx create-react-app my-app

source: https://stackoverflow.com/a/59260128/11652661

Using Lato fonts in my css (@font-face)

Well, you're missing the letter 'd' in url("~/fonts/Lato-Bol.ttf"); - but assuming that's not it, I would open up your page with developer tools in Chrome and make sure there's no errors loading any of the files (you would probably see an issue in the JavaScript console, or you can check the Network tab and see if anything is red).

(I don't see anything obviously wrong with the code you have posted above)

Other things to check: 1) Are you including your CSS file in your html above the lines where you are trying to use the font-family style? 2) What do you see in the CSS panel in the developer tools for that div? Is font-family: lato crossed out?

Use tnsnames.ora in Oracle SQL Developer

  • In SQLDeveloper browse Tools --> Preferences, as shown in below image.

    SQLDeveloper access preferences

  • In the Preferences options expand Database --> select Advanced --> under "Tnsnames Directory" --> Browse the directory where tnsnames.ora present.
  • Then click on Ok, as shown in below diagram.
    tnsnames.ora available at Drive:\oracle\product\10x.x.x\client_x\NETWORK\ADMIN

    SQLDeveloper update tnsnames directory

Now you can connect via the TNSnames options.

maxlength ignored for input type="number" in Chrome

From MDN's documentation for <input>

If the value of the type attribute is text, email, search, password, tel, or url, this attribute specifies the maximum number of characters (in Unicode code points) that the user can enter; for other control types, it is ignored.

So maxlength is ignored on <input type="number"> by design.

Depending on your needs, you can use the min and max attributes as inon suggested in his/her answer (NB: this will only define a constrained range, not the actual character length of the value, though -9999 to 9999 will cover all 0-4 digit numbers), or you can use a regular text input and enforce validation on the field with the new pattern attribute:

<input type="text" pattern="\d*" maxlength="4">

Where does System.Diagnostics.Debug.Write output appear?

While you are debugging in Visual Studio, display the "Output" window (View->Output). It will show there.

Oracle Sql get only month and year in date datatype

Easiest solution is to create the column using the correct data type: DATE

For example:

  1. Create table:

    create table test_date (mydate date);

  2. Insert row:

    insert into test_date values (to_date('01-01-2011','dd-mm-yyyy'));

To get the month and year, do as follows:

select to_char(mydate, 'MM-YYYY') from test_date;

Your result will be as follows: 01-2011

Another cool function to use is "EXTRACT"

select extract(year from mydate) from test_date;

This will return: 2011

Are there any Open Source alternatives to Crystal Reports?

You can use jasper report.

iReport is a very effective tool to develop jasper reports.

It supports almost all the facilities provided by crystal report like formatting, grouping, creation of charts etc.

Refer the link for tutorial:

http://www.opentaps.org/docs/index.php/Tutorial_iReports

A Parser-blocking, cross-origin script is invoked via document.write - how to circumvent it?

According to Google Developers article, you can:

How do I prevent people from doing XSS in Spring MVC?

How are you collecting user input in the first place? This question / answer may assist if you're using a FormController:

Spring: escaping input when binding to command

Creating a file name as a timestamp in a batch job

used Martin's suggestion with a little tweak to add time stamp to the file name:

forfiles /p [foldername] /m rsync2.log /c "cmd /c ren @file %DATE:~6,4%%DATE:~3,2%%DATE:~0,2%_%time:~-11,2%-%time:~-8,2%-%time:~-5,2%-@file

For the 10:17:21 23/10/2019 The result is:

20191023_10-17-21-rsync2.log

Prevent line-break of span element

white-space: nowrap is the correct solution but it will prevent any break in a line. If you only want to prevent line breaks between two elements it gets a bit more complicated:

<p>
    <span class="text">Some text</span>
    <span class="icon"></span>
</p>

To prevent breaks between the spans but to allow breaks between "Some" and "text" can be done by:

p {
    white-space: nowrap;
}

.text {
    white-space: normal;
}

That's good enough for Firefox. In Chrome you additionally need to replace the whitespace between the spans with an &nbsp;. (Removing the whitespace doesn't work.)

Where can I find the API KEY for Firebase Cloud Messaging?

1.Create a Firebase project in the Firebase console, if you don't already have one. If you already have an existing Google project associated with your app, click Import Google Project. Otherwise, click Create New Project.

2.Click settings and select Permissions.

3.Select Service accounts from the menu on the left.

4.Click Create service account.

  • Enter a name for your service account.
  • You can optionally customize the ID from the one automatically generated from the name.
  • Select Furnish a new private key and leave the Key type as JSON.
  • Leave Enable Google Apps Domain-wide Delegation unselected.
  • Click Create.

This might be what you're looking for. This was in the tutorial on the site

How do I name the "row names" column in r

It sounds like you want to convert the rownames to a proper column of the data.frame. eg:

# add the rownames as a proper column
myDF <- cbind(Row.Names = rownames(myDF), myDF)
myDF

#           Row.Names id val vr2
# row_one     row_one  A   1  23
# row_two     row_two  A   2  24
# row_three row_three  B   3  25
# row_four   row_four  C   4  26

If you want to then remove the original rownames:

rownames(myDF) <- NULL
myDF
#   Row.Names id val vr2
# 1   row_one  A   1  23
# 2   row_two  A   2  24
# 3 row_three  B   3  25
# 4  row_four  C   4  26


Alternatively, if all of your data is of the same class (ie, all numeric, or all string), you can convert to Matrix and name the dimnames

myMat <- as.matrix(myDF)
names(dimnames(myMat)) <- c("Names.of.Rows", "")
myMat

# Names.of.Rows id  val vr2 
#   row_one   "A" "1" "23"
#   row_two   "A" "2" "24"
#   row_three "B" "3" "25"
#   row_four  "C" "4" "26"

How to destroy a DOM element with jQuery?

Is $target.remove(); what you're looking for?

https://api.jquery.com/remove/

jQuery click events firing multiple times

In my case I had loaded the same *.js file on the page twice in a <script> tag, so both files were attaching event handlers to the element. I removed the duplicate declaration and that fixed the problem.

Consider defining a bean of type 'package' in your configuration [Spring-Boot]

I think you can make it simplified by annotated your repository with @Repository, then it will be enabled automatically by Spring Framework.

react-router - pass props to handler component

I have answered this already here.

Here are few ways you can pass props to a route component.

With the react-router v5, we can create routes by wrapping with a component, so that we can easily pass props to the desired component like this.

<Route path="/">
    <Home name="Sai" />
</Route>

Similarly, you can use the children prop in v5.

<Route path="/" children={ <Home name="Sai" />} />

If you are using react-router v4, you can pass it using the render prop.

<Route path="/" render={() => <Home name="Sai" />} />

(originally posted at https://reactgo.com/react-router-pass-props/)

What are Unwind segues for and how do you use them?

Swift iOS:

Step 1: define this method into your MASTER controller view. in which you want to go back:

//pragma mark - Unwind Seques
@IBAction func goToSideMenu(segue: UIStoryboardSegue) {

    println("Called goToSideMenu: unwind action")

}

Step 2: (StoryBoard) Right click on you SLAVE/CHILD EXIT button and Select "goToSideMenu" As action to Connect you Button on which you will click to return back to you MASTER controller view:

enter image description here step 3: Build and Run ...

How to write data to a JSON file using Javascript

JSON can be written into local storage using the JSON.stringify to serialize a JS object. You cannot write to a JSON file using only JS. Only cookies or local storage

    var obj = {"nissan": "sentra", "color": "green"};

localStorage.setItem('myStorage', JSON.stringify(obj));

And to retrieve the object later

var obj = JSON.parse(localStorage.getItem('myStorage'));

Performing user authentication in Java EE / JSF using j_security_check

The issue HttpServletRequest.login does not set authentication state in session has been fixed in 3.0.1. Update glassfish to the latest version and you're done.

Updating is quite straightforward:

glassfishv3/bin/pkg set-authority -P dev.glassfish.org
glassfishv3/bin/pkg image-update

How do I grant read access for a user to a database in SQL Server?

This is a two-step process:

  1. you need to create a login to SQL Server for that user, based on its Windows account

    CREATE LOGIN [<domainName>\<loginName>] FROM WINDOWS;
    
  2. you need to grant this login permission to access a database:

    USE (your database)
    CREATE USER (username) FOR LOGIN (your login name)
    

Once you have that user in your database, you can give it any rights you want, e.g. you could assign it the db_datareader database role to read all tables.

USE (your database)
EXEC sp_addrolemember 'db_datareader', '(your user name)'

Create patch or diff file from git repository and apply it to another different git repository

You can just use git diff to produce a unified diff suitable for git apply:

git diff tag1..tag2 > mypatch.patch

You can then apply the resulting patch with:

git apply mypatch.patch

How do you remove duplicates from a list whilst preserving order?

For no hashable types (e.g. list of lists), based on MizardX's:

def f7_noHash(seq)
    seen = set()
    return [ x for x in seq if str( x ) not in seen and not seen.add( str( x ) )]

Assigning the return value of new by reference is deprecated

I had the same problem. I already had the '&' and still it was giving the same warning. I'm using PHP 5.3 with WAMP and all i did was REMOVE '&' sign and the warning was gone.

$obj= new stdClass();  //Without '&' sign.

Cast to generic type in C#

I struggled to solve a similar problem around data table classes instead of messages. The root issue mentioned above of casting a non-generic version of the class to a derived generic version was the same.

In order to allow injection into a portable class library which did not support database libraries, I introduced a set of interface classes, with the intent that I could pass a type and get a matching generic. It ended up needing to implement a generic method.

// Interface for injection
public interface IDatabase
{
    // Original, non-functional signature:
    IDatatable<object> GetDataTable(Type dataType);

    // Functional method using a generic method:
    IDatatable<T> GetDataTable<T>();
}

And this the whole implementation using the generic method above.

The generic class that will be cast from a dictionary.

// Non-generic base class allows listing tables together
abstract class Datatable
{
    Datatable(Type storedClass)
    {
      StoredClass = storedClass;
    }

    Type StoredClass { get; private set; }
}

// Generic inheriting class
abstract class Datatable<T>: Datatable, IDatatable<T>
{
    protected Datatable()
        :base(typeof(T))
    {
    }
}

This is the class that stores the generic class and casts it to satisfy the generic method in the interface

class Database
{
    // Dictionary storing the classes using the non-generic base class
    private Dictionary<Type, Datatable> _tableDictionary;

    protected Database(List<Datatable> tables)
    {
        _tableDictionary = new Dictionary<Type, Datatable>();
        foreach (var table in tables)
        {
            _tableDictionary.Add(table.StoredClass, table);
        }
    }

    // Interface implementation, casts the generic
    public IDatatable<T> GetDataTable<T>()
    {
        Datatable table = null;

        _tableDictionary.TryGetValue(typeof(T), out table);

        return table as IDatatable<T>;
    }
}

And finally the calling of the interface method.

IDatatable<CustomerAccount> table = _database.GetDataTable<CustomerAccount>();

Git diff says subproject is dirty

Also removing the submodule and then running git submodule init and git submodule update will obviously do the trick, but may not always be appropriate or possible.

What is the difference between a JavaBean and a POJO?

Pojo - Plain old java object

pojo class is an ordinary class without any specialties,class totally loosely coupled from technology/framework.the class does not implements from technology/framework and does not extends from technology/framework api that class is called pojo class.

pojo class can implements interfaces and extend classes but the super class or interface should not be an technology/framework.

Examples :

1.

class ABC{
----
}

ABC class not implementing or extending from technology/framework that's why this is pojo class.

2.

class ABC extends HttpServlet{
---
}

ABC class extending from servlet technology api that's why this is not a pojo class.

3.

class ABC implements java.rmi.Remote{
----
}

ABC class implements from rmi api that's why this is not a pojo class.

4.

class ABC implements java.io.Serializable{
---
}

this interface is part of java language not a part of technology/framework.so this is pojo class.

5.

class ABC extends Thread{
--
}

here thread is also class of java language so this is also a pojo class.

6.

class ABC extends Test{
--
}

if Test class extends or implements from technologies/framework then ABC is also not a pojo class because it inherits the properties of Test class. if Test class is not a pojo class then ABC class also not a pojo class.

7.

now this point is an exceptional case

@Entity
class ABC{
--
}

@Entity is an annotation given by hibernate api or jpa api but still we can call this class as pojo class. class with annotations given from technology/framework is called pojo class by this exceptional case.

Custom Card Shape Flutter SDK

You can also customize the card theme globally with ThemeData.cardTheme:

MaterialApp(
  title: 'savvy',
  theme: ThemeData(
    cardTheme: CardTheme(
      shape: RoundedRectangleBorder(
        borderRadius: const BorderRadius.all(
          Radius.circular(8.0),
        ),
      ),
    ),
    // ...

How to export MySQL database with triggers and procedures?

mysqldump will backup by default all the triggers but NOT the stored procedures/functions. There are 2 mysqldump parameters that control this behavior:

  • --routines – FALSE by default
  • --triggers – TRUE by default

so in mysqldump command , add --routines like :

mysqldump <other mysqldump options> --routines > outputfile.sql

See the MySQL documentation about mysqldump arguments.

Programmatically trigger "select file" dialog box

For those who want the same but are using React

openFileInput = () => {
    this.fileInput.click()
}

<a href="#" onClick={this.openFileInput}>
    <p>Carregue sua foto de perfil</p>
    <img src={img} />
</a>
<input style={{display:'none'}} ref={(input) => { this.fileInput = input; }} type="file"/>

What is the purpose of backbone.js?

Backbone was created by Jeremy Ashkenas who also wrote CoffeeScript. As a JavaScript-heavy application, what we now know as Backbone was responsible for structuring the application into a coherent code base. Underscore.js, backbone's only dependency, was also part of the DocumentCloud application.

Backbone helps developers manage a data model in their client-side web app with as much discipline and structure as you would get in traditional server-side application logic.

Additional benefits of using Backbone.js

  1. See Backbone as a library, not as a framework
  2. Javascript is now getting organized in a structured way, the (MVVM) Model
  3. Large user community

NSUserDefaults - How to tell if a key exists

The objectForKey: method will return nil if the value does not exist. Here's a simple IF / THEN test that will tell you if the value is nil:

if([[NSUserDefaults standardUserDefaults] objectForKey:@"YOUR_KEY"] != nil) {
    ...
}

Keras, How to get the output of each layer?

Based on all the good answers of this thread, I wrote a library to fetch the output of each layer. It abstracts all the complexity and has been designed to be as user-friendly as possible:

https://github.com/philipperemy/keract

It handles almost all the edge cases

Hope it helps!

catching stdout in realtime from subprocess

I've noticed that there is no mention of using a temporary file as intermediate. The following gets around the buffering issues by outputting to a temporary file and allows you to parse the data coming from rsync without connecting to a pty. I tested the following on a linux box, and the output of rsync tends to differ across platforms, so the regular expressions to parse the output may vary:

import subprocess, time, tempfile, re

pipe_output, file_name = tempfile.TemporaryFile()
cmd = ["rsync", "-vaz", "-P", "/src/" ,"/dest"]

p = subprocess.Popen(cmd, stdout=pipe_output, 
                     stderr=subprocess.STDOUT)
while p.poll() is None:
    # p.poll() returns None while the program is still running
    # sleep for 1 second
    time.sleep(1)
    last_line =  open(file_name).readlines()
    # it's possible that it hasn't output yet, so continue
    if len(last_line) == 0: continue
    last_line = last_line[-1]
    # Matching to "[bytes downloaded]  number%  [speed] number:number:number"
    match_it = re.match(".* ([0-9]*)%.* ([0-9]*:[0-9]*:[0-9]*).*", last_line)
    if not match_it: continue
    # in this case, the percentage is stored in match_it.group(1), 
    # time in match_it.group(2).  We could do something with it here...

How to use <sec:authorize access="hasRole('ROLES)"> for checking multiple Roles?

you can try in this way if you are using thymeleaf

sec:authorize="hasAnyRole(T(com.orsbv.hcs.model.SystemRole).ADMIN.getName(),
               T(com.orsbv.hcs.model.SystemRole).SUPER_USER.getName(),'ROLE_MANAGEMENT')"

this will return true if the user has the mentioned roles,false otherwise.

Please note you have to use sec tag in your html declaration tag like this

<html xmlns:sec="http://www.thymeleaf.org/thymeleaf-extras-springsecurity4">

Easiest way to parse a comma delimited string to some kind of object I can loop through to access the individual values?

The pattern matches all non-digit characters. This will restrict you to non-negative integers, but for your example it will be more than sufficient.

string input = "0, 10, 20, 30, 100, 200";
Regex.Split(input, @"\D+");

Configuring so that pip install can work from github

Clone target repository same way like you cloning any other project:

git clone [email protected]:myuser/foo.git

Then install it in develop mode:

cd foo
pip install -e .

You can change anything you wan't and every code using foo package will use modified code.

There 2 benefits ot this solution:

  1. You can install package in your home projects directory.
  2. Package includes .git dir, so it's regular Git repository. You can push to your fork right away.

Error: No default engine was specified and no extension was provided

Error: No default engine was specified and no extension was provided

I got the same problem(for doing a mean stack project)..the problem is i didn't mentioned the formate to install npm i.e; pug or jade,ejs etc. so to solve this goto npm and enter express --view=pug foldername. This will load necessary pug files(index.pug,layout.pug etc..) in ur given folder .

How to export SQL Server 2005 query to CSV

You can use following Node.js module to do it with a breeze:

https://www.npmjs.com/package/mssql-to-csv

Getting data-* attribute for onclick event for an html element

You can achieve this $(identifier).data('id') using jquery,

    <script type="text/javascript">

        function goDoSomething(identifier){     
            alert("data-id:"+$(identifier).data('id')+", data-option:"+$(identifier).data('option'));               
        }

    </script>

    <a id="option1" 
       data-id="10" 
       data-option="21" 
       href="#" 
       onclick="goDoSomething(this);">
           Click to do something
    </a>

javascript : You can use getAttribute("attributename") if want to use javascript tag,

    <script type="text/javascript">

        function goDoSomething(d){
            alert(d.getAttribute("data-id"));
        }

    </script>

    <a id="option1" 
       data-id="10" 
       data-option="21" 
       href="#" 
       onclick="goDoSomething(this);">
           Click to do something
    </a>

Or:

    <script type="text/javascript">

        function goDoSomething(data_id, data_option){       

            alert("data-id:"+data_id+", data-option:"+data_option);
        }

    </script>

    <a id="option1" 
       data-id="10" 
       data-option="21" 
       href="#" 
       onclick="goDoSomething(this.getAttribute('data-id'), this.getAttribute('data-option'));">
           Click to do something
    </a>

Switch statement fall-through...should it be allowed?

Using fall-through like in your first example is clearly OK, and I would not consider it a real fall-through.

The second example is dangerous and (if not commented extensively) non-obvious. I teach my students not to use such constructs unless they consider it worth the effort to devote a comment block to it, which describes that this is an intentional fall-through, and why this solution is better than the alternatives. This discourages sloppy use, but it still makes it allowed in the cases where it is used to an advantage.

This is more or less equivalent to what we did in space projects when someone wanted to violate the coding standard: they had to apply for dispensation (and I was called on to advise about the ruling).

What are Runtime.getRuntime().totalMemory() and freeMemory()?

You can see the results in MB format, with the division of 1024 x 1024 which is equal to 1 MB.

int dataSize = 1024 * 1024;

System.out.println("Used Memory   : " + (Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory())/dataSize + " MB");
System.out.println("Free Memory   : " + Runtime.getRuntime().freeMemory()/dataSize + " MB");
System.out.println("Total Memory  : " + Runtime.getRuntime().totalMemory()/dataSize + " MB");
System.out.println("Max Memory    : " + Runtime.getRuntime().maxMemory()/dataSize + " MB");  

MySQL Multiple Left Joins

To display the all details for each news post title ie. "news.id" which is the primary key, you need to use GROUP BY clause for "news.id"

SELECT news.id, users.username, news.title, news.date,
       news.body, COUNT(comments.id)
FROM news
LEFT JOIN users
ON news.user_id = users.id
LEFT JOIN comments
ON comments.news_id = news.id
GROUP BY news.id

How to display pie chart data values of each slice in chart.js

I found an excellent Chart.js plugin that does exactly what you want: https://github.com/emn178/Chart.PieceLabel.js

Indent multiple lines quickly in vi

For mac,

  1. Open the file using vim

    vim deploy1.yml

  2. Select lines using Shift + 'v' and then using 'up' or 'down' key

    enter image description here

  3. Indent selected lines using Shift + '>' or Shift + '<'

    enter image description here

Converting XDocument to XmlDocument and vice versa

If you need a Win 10 UWP compatible variant:

using DomXmlDocument = Windows.Data.Xml.Dom.XmlDocument;

    public static class DocumentExtensions
    {
        public static XmlDocument ToXmlDocument(this XDocument xDocument)
        {
            var xmlDocument = new XmlDocument();
            using (var xmlReader = xDocument.CreateReader())
            {
                xmlDocument.Load(xmlReader);
            }
            return xmlDocument;
        }

        public static DomXmlDocument ToDomXmlDocument(this XDocument xDocument)
        {
            var xmlDocument = new DomXmlDocument();
            using (var xmlReader = xDocument.CreateReader())
            {
                xmlDocument.LoadXml(xmlReader.ReadOuterXml());
            }
            return xmlDocument;
        }

        public static XDocument ToXDocument(this XmlDocument xmlDocument)
        {
            using (var memStream = new MemoryStream())
            {
                using (var w = XmlWriter.Create(memStream))
                {
                    xmlDocument.WriteContentTo(w);
                }
                memStream.Seek(0, SeekOrigin.Begin);
                using (var r = XmlReader.Create(memStream))
                {
                    return XDocument.Load(r);
                }
            }
        }

        public static XDocument ToXDocument(this DomXmlDocument xmlDocument)
        {
            using (var memStream = new MemoryStream())
            {
                using (var w = XmlWriter.Create(memStream))
                {
                    w.WriteRaw(xmlDocument.GetXml());
                }
                memStream.Seek(0, SeekOrigin.Begin);
                using (var r = XmlReader.Create(memStream))
                {
                    return XDocument.Load(r);
                }
            }
        }
    }

Do I need to pass the full path of a file in another directory to open()?

Yes, you need the full path.

log = open(os.path.join(root, f), 'r')

Is the quick fix. As the comment pointed out, os.walk decends into subdirs so you do need to use the current directory root rather than indir as the base for the path join.

How to insert multiple rows from a single query using eloquent/fluent

It is really easy to do a bulk insert in Laravel using Eloquent or the query builder.

You can use the following approach.

$data = [
    ['user_id'=>'Coder 1', 'subject_id'=> 4096],
    ['user_id'=>'Coder 2', 'subject_id'=> 2048],
    //...
];

Model::insert($data); // Eloquent approach
DB::table('table')->insert($data); // Query Builder approach

In your case you already have the data within the $query variable.

ls command: how can I get a recursive full-path listing, one line per file?

The easiest way for all you future people is simply:

du

This however, also shows the size of whats contained in each folder You can use awk to output only the folder name:

du | awk '{print $2}'

Edit- Sorry sorry, my bad. I thought it was only folders that were needed. Ill leave this here in case anyone in the future needs it anyways...

Can I run multiple versions of Google Chrome on the same machine? (Mac or Windows)

I adopted @RobW's nice answer to get it working on Mac OS X 10.8. Other versions of Mac OS X may probably work too.

The little extra work is actually only needed to keep your original Google Chrome user settings and the old version separated.

  1. Download another version of Google Chrome, like the Dev channel and extract the .app file

  2. (optional) Rename it to Google Chrome X.app – if not already different from Google Chrome.app

(Be sure to replace X for all following steps with the actual version of Chrome you just downloaded)

  1. Move Google Chrome X.app to /Applications without overwritting your current Chrome

  2. Open the Terminal, create a shell script and make your script executable:

    cd /Applications
    touch google-chrome-version-start.sh
    chmod +x google-chrome-version-start.sh
    nano google-chrome-version-start.sh
    
  3. Modify the following code according to the version you downloaded and paste it into the script

    #!/usr/bin/env bash
    /Applications/Google\ Chrome\ X.app/Contents/MacOS/Google\ Chrome\ X --user-data-dir="tmp/Google Chrome/X/" & disown
    

    For example for Dev Channel:

    #!/usr/bin/env bash
    /Applications/Google\ Chrome\ Dev.app/Contents/MacOS/Google\ Chrome\ Dev --user-data-dir="tmp/Google Chrome Dev/" & disown
    

    (This will store Chrome's data at ~/tmp/Google Chrome/VERSION/. For more explanations see the original answer.)

  4. Now execute the script and be happy!

    /Application/google-chrome-version-start.sh
    

Tested it with Google Chrome 88 on a Mac running OS X 10.15 Catalina

Validating URL in Java

Are you sure you're using the correct proxy as system properties?

Also if you are using 1.5 or 1.6 you could pass a java.net.Proxy instance to the openConnection() method. This is more elegant imo:

//Proxy instance, proxy ip = 10.0.0.1 with port 8080
Proxy proxy = new Proxy(Proxy.Type.HTTP, new InetSocketAddress("10.0.0.1", 8080));
conn = new URL(urlString).openConnection(proxy);

MySQL CREATE FUNCTION Syntax

MySQL create function syntax:

DELIMITER //

CREATE FUNCTION GETFULLNAME(fname CHAR(250),lname CHAR(250))
    RETURNS CHAR(250)
    BEGIN
        DECLARE fullname CHAR(250);
        SET fullname=CONCAT(fname,' ',lname);
        RETURN fullname;
    END //

DELIMITER ;

Use This Function In Your Query

SELECT a.*,GETFULLNAME(a.fname,a.lname) FROM namedbtbl as a


SELECT GETFULLNAME("Biswarup","Adhikari") as myname;

Watch this Video how to create mysql function and how to use in your query

Create Mysql Function Video Tutorial

Wait Until File Is Completely Written

When the file is writing in binary(byte by byte),create FileStream and above solutions Not working,because file is ready and wrotted in every bytes,so in this Situation you need other workaround like this: Do this when file created or you want to start processing on file

long fileSize = 0;
currentFile = new FileInfo(path);

while (fileSize < currentFile.Length)//check size is stable or increased
{
  fileSize = currentFile.Length;//get current size
  System.Threading.Thread.Sleep(500);//wait a moment for processing copy
  currentFile.Refresh();//refresh length value
}

//Now file is ready for any process!

How to set time zone of a java.util.Date?

Convert the Date to String and do it with SimpleDateFormat.

    SimpleDateFormat readFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
    readFormat.setTimeZone(TimeZone.getTimeZone("GMT" + timezoneOffset));
    String dateStr = readFormat.format(date);
    SimpleDateFormat writeFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
    Date date = writeFormat.parse(dateStr);

C# delete a folder and all files and folders within that folder

Err, what about just calling Directory.Delete(path, true); ?

How do I prevent a Gateway Timeout with FastCGI on Nginx

In server proxy set like that

location / {

                proxy_pass http://ip:80;                

                proxy_connect_timeout   90;
                proxy_send_timeout      90;
                proxy_read_timeout      90;

            }

In server php set like that

server {
        client_body_timeout 120;
        location = /index.php {

                #include fastcgi.conf; //example
                #fastcgi_pass unix:/run/php/php7.3-fpm.sock;//example veriosn

                fastcgi_read_timeout 120s;
       }
}

How can I install a .ipa file to my iPhone simulator

Update for Xcode 9.4.1+

Hope my answer is getting seen down here as this took me a while to figure out but I just got it working.

First of all you need to build and run the App on your simulator. Then you open the Activity Monitor. Double click the name of your App to find its content.

enter image description here

In the next screen open the Open Files and Ports tab and find the line with MyAppName.app/MyAppName.

enter image description here

Copy the link but make sure to stop at the MyAppName.app. Do not copy the path following it.

Control click onto the finder icon and select Go to folder.

enter image description here]

Paste the path and click enter. You will see your MyAppName.app file. Copy it to the Desktop and zip it. Move it to your desired 2nd computer and unzip the file. Build a random project to have a simulator open.

Lastly: Literally drag and drop the App from your Desktop into your Simulator. You will see the install and the App opens and does not crash.

enter image description here

Python reading from a file and saving to utf-8

Process text to and from Unicode at the I/O boundaries of your program using open with the encoding parameter. Make sure to use the (hopefully documented) encoding of the file being read. The default encoding varies by OS (specifically, locale.getpreferredencoding(False) is the encoding used), so I recommend always explicitly using the encoding parameter for portability and clarity (Python 3 syntax below):

with open(filename, 'r', encoding='utf8') as f:
    text = f.read()

# process Unicode text

with open(filename, 'w', encoding='utf8') as f:
    f.write(text)

If still using Python 2 or for Python 2/3 compatibility, the io module implements open with the same semantics as Python 3's open and exists in both versions:

import io
with io.open(filename, 'r', encoding='utf8') as f:
    text = f.read()

# process Unicode text

with io.open(filename, 'w', encoding='utf8') as f:
    f.write(text)

hide/show a image in jquery

With image class name:

$('.img_class').hide(); // to hide image
$('.img_class').show(); // to show image

With image Id :

$('#img_id').hide(); // to hide image
$('#img_id').show(); // to show image

Convert Unicode to ASCII without errors in Python

2018 Update:

As of February 2018, using compressions like gzip has become quite popular (around 73% of all websites use it, including large sites like Google, YouTube, Yahoo, Wikipedia, Reddit, Stack Overflow and Stack Exchange Network sites).
If you do a simple decode like in the original answer with a gzipped response, you'll get an error like or similar to this:

UnicodeDecodeError: 'utf8' codec can't decode byte 0x8b in position 1: unexpected code byte

In order to decode a gzpipped response you need to add the following modules (in Python 3):

import gzip
import io

Note: In Python 2 you'd use StringIO instead of io

Then you can parse the content out like this:

response = urlopen("https://example.com/gzipped-ressource")
buffer = io.BytesIO(response.read()) # Use StringIO.StringIO(response.read()) in Python 2
gzipped_file = gzip.GzipFile(fileobj=buffer)
decoded = gzipped_file.read()
content = decoded.decode("utf-8") # Replace utf-8 with the source encoding of your requested resource

This code reads the response, and places the bytes in a buffer. The gzip module then reads the buffer using the GZipFile function. After that, the gzipped file can be read into bytes again and decoded to normally readable text in the end.

Original Answer from 2010:

Can we get the actual value used for link?

In addition, we usually encounter this problem here when we are trying to .encode() an already encoded byte string. So you might try to decode it first as in

html = urllib.urlopen(link).read()
unicode_str = html.decode(<source encoding>)
encoded_str = unicode_str.encode("utf8")

As an example:

html = '\xa0'
encoded_str = html.encode("utf8")

Fails with

UnicodeDecodeError: 'ascii' codec can't decode byte 0xa0 in position 0: ordinal not in range(128)

While:

html = '\xa0'
decoded_str = html.decode("windows-1252")
encoded_str = decoded_str.encode("utf8")

Succeeds without error. Do note that "windows-1252" is something I used as an example. I got this from chardet and it had 0.5 confidence that it is right! (well, as given with a 1-character-length string, what do you expect) You should change that to the encoding of the byte string returned from .urlopen().read() to what applies to the content you retrieved.

Another problem I see there is that the .encode() string method returns the modified string and does not modify the source in place. So it's kind of useless to have self.response.out.write(html) as html is not the encoded string from html.encode (if that is what you were originally aiming for).

As Ignacio suggested, check the source webpage for the actual encoding of the returned string from read(). It's either in one of the Meta tags or in the ContentType header in the response. Use that then as the parameter for .decode().

Do note however that it should not be assumed that other developers are responsible enough to make sure the header and/or meta character set declarations match the actual content. (Which is a PITA, yeah, I should know, I was one of those before).

python: get directory two levels up

You can use this as a generic solution:

import os

def getParentDir(path, level=1):
  return os.path.normpath( os.path.join(path, *([".."] * level)) )

CodeIgniter - accessing $config variable in view

$this->config->item() works fine.

For example, if the config file contains $config['foo'] = 'bar'; then $this->config->item('foo') == 'bar'

How do I calculate a point on a circle’s circumference?

Calculating point around circumference of circle given distance travelled.
For comparison... This may be useful in Game AI when moving around a solid object in a direct path.

enter image description here

public static Point DestinationCoordinatesArc(Int32 startingPointX, Int32 startingPointY,
    Int32 circleOriginX, Int32 circleOriginY, float distanceToMove,
    ClockDirection clockDirection, float radius)
{
    // Note: distanceToMove and radius parameters are float type to avoid integer division
    // which will discard remainder

    var theta = (distanceToMove / radius) * (clockDirection == ClockDirection.Clockwise ? 1 : -1);
    var destinationX = circleOriginX + (startingPointX - circleOriginX) * Math.Cos(theta) - (startingPointY - circleOriginY) * Math.Sin(theta);
    var destinationY = circleOriginY + (startingPointX - circleOriginX) * Math.Sin(theta) + (startingPointY - circleOriginY) * Math.Cos(theta);

    // Round to avoid integer conversion truncation
    return new Point((Int32)Math.Round(destinationX), (Int32)Math.Round(destinationY));
}

/// <summary>
/// Possible clock directions.
/// </summary>
public enum ClockDirection
{
    [Description("Time moving forwards.")]
    Clockwise,
    [Description("Time moving moving backwards.")]
    CounterClockwise
}

private void ButtonArcDemo_Click(object sender, EventArgs e)
{
    Brush aBrush = (Brush)Brushes.Black;
    Graphics g = this.CreateGraphics();

    var startingPointX = 125;
    var startingPointY = 75;
    for (var count = 0; count < 62; count++)
    {
        var point = DestinationCoordinatesArc(
            startingPointX: startingPointX, startingPointY: startingPointY,
            circleOriginX: 75, circleOriginY: 75,
            distanceToMove: 5,
            clockDirection: ClockDirection.Clockwise, radius: 50);
        g.FillRectangle(aBrush, point.X, point.Y, 1, 1);

        startingPointX = point.X;
        startingPointY = point.Y;

        // Pause to visually observe/confirm clock direction
        System.Threading.Thread.Sleep(35);

        Debug.WriteLine($"DestinationCoordinatesArc({point.X}, {point.Y}");
    }
}

Append text using StreamWriter

Also look at log4net, which makes logging to 1 or more event stores — whether it's the console, the Windows event log, a text file, a network pipe, a SQL database, etc. — pretty trivial. You can even filter stuff in its configuration, for instance, so that only log records of a particular severity (say ERROR or FATAL) from a single component or assembly are directed to a particular event store.

http://logging.apache.org/log4net/

Convert long/lat to pixel x/y on a given picture

Struggled with this - Have both openstreet map and google street map and wanted to project an external graphic image

var map = new OpenLayers.Map({
            div:"map-id",
            allOverlays: true
    });
    var osm = new OpenLayers.Layer.OSM("OpenStreeMao");
    var gmap = new OpenLayers.Layer.Google("Google Streets", {visibility: false});

    map.addLayers([osm,gmap]);

    var vectorLayer = new OpenLayers.Layer.Vector("IconLayer");


    var lonlatObject = new OpenLayers.LonLat(24.938622,60.170421).transform(
            new OpenLayers.Projection("EPSG:4326"), map.getProjectionObject()
    );
    console.log(lonlatObject);

    var point = new OpenLayers.Geometry.Point(lonlatObject.lon, lonlatObject.lat);
    console.log(point);

    var point2 = new OpenLayers.Geometry.Point(lonlatObject.x, lonlatObject.y);
    console.log(point2);

    var feature = new OpenLayers.Feature.Vector(point, null, {
        externalGraphic:  "http://cdn1.iconfinder.com/data/icons/SUPERVISTA/networking/png/72/antenna.png",
        graphicWidth: 72,
        graphicHeight: 72,
        fillOpacity: 1
    });


    vectorLayer.addFeatures(feature);

    map.addLayer(vectorLayer);


    map.setCenter(
            new OpenLayers.LonLat(24.938622,60.170421).transform(
            new OpenLayers.Projection("EPSG:4326"), map.getProjectionObject()
            ),
            12);

     map.addControl(new OpenLayers.Control.LayerSwitcher());

http://jsfiddle.net/alexcpn/N9dLN/8/

Updating a date in Oracle SQL table

If this SQL is being used in any peoplesoft specific code (Application Engine, SQLEXEC, SQLfetch, etc..) you could use %Datein metaSQL. Peopletools automatically converts the date to a format which would be accepted by the database platform the application is running on.

In case this SQL is being used to perform a backend update from a query analyzer (like SQLDeveloper, SQLTools), the date format that is being used is wrong. Oracle expects the date format to be DD-MMM-YYYY, where MMM could be JAN, FEB, MAR, etc..

python-pandas and databases like mysql

For Postgres users

import psycopg2
import pandas as pd

conn = psycopg2.connect("database='datawarehouse' user='user1' host='localhost' password='uberdba'")

customers = 'select * from customers'

customers_df = pd.read_sql(customers,conn)

customers_df

How to get relative path from absolute path

The function that uses URI returned "almost" relative path. It included directory that directly contains the file which relative path I wanted to get.

Some time ago I wrote a simple function that returns relative path of folder or file, and even if it's on another drive, it includes the drive letter as well.

Please take a look:

    public static string GetRelativePath(string BasePath, string AbsolutePath)
    {
        char Separator = Path.DirectorySeparatorChar;
        if (string.IsNullOrWhiteSpace(BasePath)) BasePath = Directory.GetCurrentDirectory();
        var ReturnPath = "";
        var CommonPart = "";
        var BasePathFolders = BasePath.Split(Separator);
        var AbsolutePathFolders = AbsolutePath.Split(Separator);
        var i = 0;
        while (i < BasePathFolders.Length & i < AbsolutePathFolders.Length)
        {
            if (BasePathFolders[i].ToLower() == AbsolutePathFolders[i].ToLower())
            {
                CommonPart += BasePathFolders[i] + Separator;
            }
            else
            {
                break;
            }
            i += 1;
        }
        if (CommonPart.Length > 0)
        {
            var parents = BasePath.Substring(CommonPart.Length - 1).Split(Separator);
            foreach (var ParentDir in parents)
            {
                if (!string.IsNullOrEmpty(ParentDir))
                    ReturnPath += ".." + Separator;
            }
        }
        ReturnPath += AbsolutePath.Substring(CommonPart.Length);
        return ReturnPath;
    }

IntelliJ and Tomcat.. Howto..?

Which version of IntelliJ are you using? Note that since last year, IntelliJ exists in two versions:

  • Ultimate Edition, which is the complete IDE
  • Community Edition, which is free but does not support JavaEE developments.

(see differences here)

In case you are using the Community Edition, you will not be able to manage a Tomcat installation.

In case you are using the Ultimate Edition, you can have a look at:

delete a column with awk or sed

If you're open to a Perl solution...

perl -ane 'print "$F[0] $F[1]\n"' file

These command-line options are used:

  • -n loop around every line of the input file, do not automatically print every line

  • -a autosplit mode – split input lines into the @F array. Defaults to splitting on whitespace

  • -e execute the following perl code

How to use goto statement correctly

The Java keyword list specifies the goto keyword, but it is marked as "not used".

This was probably done in case it were to be added to a later version of Java.

If goto weren't on the list, and it were added to the language later on, existing code that used the word goto as an identifier (variable name, method name, etcetera) would break. But because goto is a keyword, such code will not even compile in the present, and it remains possible to make it actually do something later on, without breaking existing code.

How do I combine two dataframes?

If you want to update/replace the values of first dataframe df1 with the values of second dataframe df2. you can do it by following steps —

Step 1: Set index of the first dataframe (df1)

df1.set_index('id')

Step 2: Set index of the second dataframe (df2)

df2.set_index('id')

and finally update the dataframe using the following snippet —

df1.update(df2)

Uncaught ReferenceError: jQuery is not defined

you need to put it after wp_head(); Because that loads your jQuery and you need to load jQuery first and then your js

How do I use Spring Boot to serve static content located in Dropbox folder?

FWIW, I didn't have any success with the spring.resources.static-locations recommended above; what worked for me was setting spring.thymeleaf.prefix:

report.location=file:/Users/bill/report/html/
spring.thymeleaf.prefix=${report.location}

R command for setting working directory to source file location in Rstudio

dirname(rstudioapi::getActiveDocumentContext()$path)

works for me but if you don't want to use rstudioapi and you are not in a proyect, you can use the symbol ~ in your path. The symbol ~ refers to the default RStudio working directory (at least on Windows).

RStudio options

If your RStudio working directory is "D:/Documents", setwd("~/proyect1") is the same as setwd("D:/Documents/proyect1").

Once you set that, you can navigate to a subdirectory: read.csv("DATA/mydata.csv"). Is the same as read.csv("D:/Documents/proyect1/DATA/mydata.csv").

If you want to navigate to a parent folder, you can use "../". For example: read.csv("../olddata/DATA/mydata.csv") which is the same as read.csv("D:/Documents/oldata/DATA/mydata.csv")

This is the best way for me to code scripts, no matter what computer you are using.

Error while waiting for device: Time out after 300seconds waiting for emulator to come online

Sadly none of the solutions worked for me! I solved my problem by uninstalling existing APK from my phone and it all started working perfectly!

This started happening after I've updated android studio to latest version.

Size of Matrix OpenCV

cv:Mat mat;
int rows = mat.rows;
int cols = mat.cols;

cv::Size s = mat.size();
rows = s.height;
cols = s.width;

Also note that stride >= cols; this means that actual size of the row can be greater than element size x cols. This is different from the issue of continuous Mat and is related to data alignment.

Write variable to a file in Ansible

Unless you are writing very small files, you should probably use templates.

Example:

- name: copy upstart script
  template: 
    src: myCompany-service.conf.j2 
    dest: "/etc/init/myCompany-service.conf"

Multiline text in JLabel

You can use JTextArea and remove editing capabilities to get normal read-only multiline text.

JTextArea textArea = new JTextArea("line\nline\nline");
textArea.setEditable(false);

JTextArea

setEditable

What does the exclamation mark do before the function?

Its another way of writing IIFE (immediately-invoked function expression).

Its other way of writing -

(function( args ) {})()

same as

!function ( args ) {}();

Resizing an Image without losing any quality

Here is a forum thread that provides a C# image resizing code sample. You could use one of the GD library binders to do resampling in C#.

Apply Calibri (Body) font to text

There is no such font as “Calibri (Body)”. You probably saw this string in Microsoft Word font selection menu, but it’s not a font name (see e.g. the explanation Font: +body (in W07)).

So use just font-family: Calibri or, better, font-family: Calibri, sans-serif. (There is no adequate backup font for Calibri, but the odds are that when Calibri is not available, the browser’s default sans-serif font suits your design better than the browser’s default font, which is most often a serif font.)

HTTP Status 405 - Method Not Allowed Error for Rest API

You might be doing a PUT call for GET operation Please check once

Why does Java have an "unreachable statement" compiler error?

There is no definitive reason why unreachable statements must be not be allowed; other languages allow them without problems. For your specific need, this is the usual trick:

if (true) return;

It looks nonsensical, anyone who reads the code will guess that it must have been done deliberately, not a careless mistake of leaving the rest of statements unreachable.

Java has a little bit support for "conditional compilation"

http://java.sun.com/docs/books/jls/third_edition/html/statements.html#14.21

if (false) { x=3; }

does not result in a compile-time error. An optimizing compiler may realize that the statement x=3; will never be executed and may choose to omit the code for that statement from the generated class file, but the statement x=3; is not regarded as "unreachable" in the technical sense specified here.

The rationale for this differing treatment is to allow programmers to define "flag variables" such as:

static final boolean DEBUG = false;

and then write code such as:

if (DEBUG) { x=3; }

The idea is that it should be possible to change the value of DEBUG from false to true or from true to false and then compile the code correctly with no other changes to the program text.

How to remove line breaks from a file in Java?

You can use apache commons IOUtils to iterate through the line and append each line to StringBuilder. And don't forget to close the InputStream

StringBuilder sb = new StringBuilder();
FileInputStream fin=new FileInputStream("textfile.txt");
LineIterator lt=IOUtils.lineIterator(fin, "utf-8");
while(lt.hasNext())
{
  sb.append(lt.nextLine());
}
String text = sb.toString();
IOUtils.closeQuitely(fin);

How to merge every two lines into one from the command line?

There are more ways to kill a dog than hanging. [1]

awk '{key=$0; getline; print key ", " $0;}'

Put whatever delimiter you like inside the quotes.


References:

  1. Originally "Plenty of ways to skin the cat", reverted to an older, potentially originating expression that also has nothing to do with pets.

Attempt to present UIViewController on UIViewController whose view is not in the window hierarchy

I just had this issue too, but it had nothing to do with the timing. I was using a singleton to handle scenes, and I set it as the presenter. In other words "Self" wasn't hooked up to anything. I just made its inner "scene" the new presenter and voila, it worked. (Voila loses its touch after you learn its meaning, heh).

So yeah, it's not about "magically finding the right way", it's about understanding where your code stands and what it's doing. I'm happy Apple gave such a plain-English warning message, even with emotion to it. Kudos to the apple dev who did that!!

How to code a BAT file to always run as admin mode?

go get github.com/mattn/sudo

Then

sudo Example1Server.exe

Unexpected 'else' in "else" error

You need to rearrange your curly brackets. Your first statement is complete, so R interprets it as such and produces syntax errors on the other lines. Your code should look like:

if (dsnt<0.05) {
  wilcox.test(distance[result=='nt'],distance[result=='t'],alternative=c("two.sided"),paired=TRUE)
} else if (dst<0.05) {
  wilcox.test(distance[result=='nt'],distance[result=='t'],alternative=c("two.sided"),paired=TRUE)
} else {
  t.test(distance[result=='nt'],distance[result=='t'],alternative=c("two.sided"),paired=TRUE)       
} 

To put it more simply, if you have:

if(condition == TRUE) x <- TRUE
else x <- FALSE

Then R reads the first line and because it is complete, runs that in its entirety. When it gets to the next line, it goes "Else? Else what?" because it is a completely new statement. To have R interpret the else as part of the preceding if statement, you must have curly brackets to tell R that you aren't yet finished:

if(condition == TRUE) {x <- TRUE
 } else {x <- FALSE}

SQL: parse the first, middle and last name from a fullname field

Check this query in Athena for only one-space separated string (e.g. first name and middle name combination):

SELECT name, REVERSE( SUBSTR( REVERSE(name), 1, STRPOS(REVERSE(name), ' ') ) ) AS middle_name FROM name_table

If you expect to have two or more spaces, you can easily extend the above query.