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Some Of The Best Answers From Latest Asked Questions

How to format DateTime in Flutter , How to get current time in flutter?

Here's my simple solution. That does not require any dependency.

However, the date will be in string format. If you want the time then change the substring values

print(new DateTime.now()
            .toString()
            .substring(0,10)
     );   // 2020-06-10

Flutter : Vertically center column

You control how a row or column aligns its children using the mainAxisAlignment and crossAxisAlignment properties. For a row, the main axis runs horizontally and the cross axis runs vertically. For a column, the main axis runs vertically and the cross axis runs horizontally.

 mainAxisAlignment: MainAxisAlignment.center,
 crossAxisAlignment: CrossAxisAlignment.center,

Angular 6: saving data to local storage

First you should understand how localStorage works. you are doing wrong way to set/get values in local storage. Please read this for more information : How to Use Local Storage with JavaScript

How to change package name in flutter?

Change App Package Name easily using change_app_package_name package

just add the above package in dev dependencies

dev_dependencies:
  flutter_test:
    sdk: flutter
  change_app_package_name: ^0.1.2

and run the following command, replace "com.new.package.name" with your new package name

flutter pub run change_app_package_name:main com.new.package.name

Package Link on Pub Dev

screenshot of Package

Rounded Corners Image in Flutter

Using ClipRRect you need to hardcode BorderRadius, so if you need complete circular stuff, use ClipOval instead.

ClipOval(
  child: Image.network(
    "image_url",
    height: 100,
    width: 100,
    fit: BoxFit.cover,
  ),
),

Best way to "push" into C# array

C# is a little different in this respect with JavaScript. Because of the strict checks, you define the size of the array and you are supposed to know everything about the array such as its bounds, where the last item was put and what items are unused. You are supposed to copy all the elements of the array into a new, bigger one, if you want to resize it.

So, if you use a raw array, there's no other way other than to maintain the last empty, available index assign items to the array at this index, like you're already doing.

However, if you'd like to have the runtime maintain this information and completely abstract away the array, but still use an array underneath, then C# provides a class named ArrayList that provides this abstraction.

The ArrayList abstracts a loosely typed array of Objects. See the source here.

It takes care of all the issues like resizing the array, maintaining the last index that is available, etc. However, it abstracts / encapsulates this information from you. All you use is the ArrayList.

To push an item of any type into the underlying array at the end of the underlying array, call the Add method on the ArrayList like so:

/* you may or may not define a size using a constructor overload */
var arrayList = new ArrayList(); 

arrayList.Add("Foo");

EDIT: A note about type restriction

Like every programming language and runtime does, C# categorizes heap objects from those that will not go on the heap and will only stay on the function's argument stack. C# notes this distinction by the name Value types vs. Reference types. All things whose value goes on the stack are called Value types, and those that will go on the heap are called Reference types. This is loosely similar to JavaScript's distinction between objects and literals.

You can put anything into an ArrayList in C#, whether the thing is a value type or a reference type. This makes it closest to the JavaScript array in terms of typelessness, although neither of the three -- the JavaScript array, the JavaScript language and the C# ArrayList -- are actually type-less.

So, you could put a number literal, a string literal, an object of a class you made up, a boolean, a float, a double, a struct, just about anything you wanted into an ArrayList.

That is because the ArrayList internally maintains and stores all that you put into it, into an array of Objects, as you will have noted in my original answer and the linked source code.

And when you put something that isn't an object, C# creates a new object of type Object, stores the value of the thing you put into the ArrayList into this new Object type object. This process is called boxing and isn't very much unlike the JavaScript boxing mechanism.

For e.g. in JavaScript, while you could use a numeric literal to invoke a function on the Number object, you couldn't add something to the number literal's prototype.

// Valid javascript
var s = 4.toString();

// Invalid JavaScript code
4.prototype.square = () => 4 * 4;
var square = 4.square();

Just like JavaScript boxes the numeric literal 4 in the call to the toString method, C# boxes all things that are not objects into an Object type when putting them into an ArrayList.

var arrayList = new ArrayList();

arrayList.Add(4); // The value 4 is boxed into a `new Object()` first and then that new object is inserted as the last element in the `ArrayList`.

This involves a certain penalty, as it does in the case of JavaScript as well.

In C#, you can avoid this penalty as C# provides a strongly typed version of the ArrayList, known as the List<T>. So it follows that you cannot put anything into a List<T>; just T types.

However, I assume from your question's text that you already knew that C# had generic structures for strongly typed items. And your question was to have a JavaScript like data structure exhibiting the semantics of typelessness and elasticity, like the JavaScript Array object. In this case, the ArrayList comes closest.

It is also clear from your question that your interest was academic and not to use the structure in a production application.

So, I assume that for a production application, you would already know that a generic / strongly typed data structure (List<T> for example) is better performing than its non-typed one (ArrayList for example).

Problems after upgrading to Xcode 10: Build input file cannot be found

open the right navigation pane where your project files exist OR JSUT click on cmd + 1 Then search for "Recovered References" Folder open it all red files (delete them) then everything will work so fine .

How to reload current page?

I found a better way than reload the page. instead i will reload the data that just got updated. this way faster n better

Command CompileSwift failed with a nonzero exit code in Xcode 10

I had this issue and changing the Compilation Mode setting for the project from Incremental to Whole Module fixed it for me.

enter image description here

Jenkins pipeline how to change to another folder

The dir wrapper can wrap, any other step, and it all works inside a steps block, for example:

steps {
    sh "pwd"
    dir('your-sub-directory') {
      sh "pwd"
    }
    sh "pwd"
} 

PHP with MySQL 8.0+ error: The server requested authentication method unknown to the client

i've try a lot of ways, but only this work for me

thanks for workaround

check your .env

MYSQL_VERSION=latest

then type this command

$ docker-compose exec mysql bash
$ mysql -u root -p 

(login as root)

ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'root';
ALTER USER 'root'@'%' IDENTIFIED WITH mysql_native_password BY 'root';
ALTER USER 'default'@'%' IDENTIFIED WITH mysql_native_password BY 'secret';

then go to phpmyadmin and login as :

  • host -> mysql
  • user -> root
  • password -> root

hope it help

Center content vertically on Vuetify

Still surprised that no one proposed the shortest solution with align-center justify-center to center content vertically and horizontally. Check this CodeSandbox and code below:

<v-container fluid fill-height>
  <v-layout align-center justify-center>
    <v-flex>
      <!-- Some HTML elements... -->
    </v-flex>
  </v-layout>
</v-container>

I can't install pyaudio on Windows? How to solve "error: Microsoft Visual C++ 14.0 is required."?

The problem is pyaudio does not have wheels for python 3.7 just try some lower version like 3.6 then install pyaudio

It works

OpenJDK8 for windows

Go to this link

Download version tar.gz for windows and just extract files to the folder by your needs. On the left pane, you can select which version of openjdk to download

Tutorial: unzip as expected. You need to set system variable PATH to include your directory with openjdk so you can type java -version in console.

JDK vs OpenJDK

GoogleMaps API KEY for testing

Updated Answer

As of June11, 2018 it is now mandatory to have a billing account to get API key. You can still make keyless calls to the Maps JavaScript API and Street View Static API which will return low-resolution maps that can be used for development. Enabling billing still gives you $200 free credit monthly for your projects.

This answer is no longer valid

As long as you're using a testing API key it is free to register and use. But when you move your app to commercial level you have to pay for it. When you enable billing, google gives you $200 credit free each month that means if your app's map usage is low you can still use it for free even after the billing enabled, if it exceeds the credit limit now you have to pay for it.

How to open a link in new tab using angular?

Use window.open(). It's pretty straightforward !

In your component.html file-

<a (click)="goToLink("www.example.com")">page link</a>

In your component.ts file-

goToLink(url: string){
    window.open(url, "_blank");
}

Support for the experimental syntax 'classProperties' isn't currently enabled

Moving the state inside the constructor function worked for me:

...
class MyComponent extends Component {
  constructor(man) {
    super(man)
    this.state = {}
  }
}
...

Good Luck...

How can I add shadow to the widget in flutter?

Use Material with shadowColor inside Container like this:

Container(
  decoration: BoxDecoration(
      borderRadius: BorderRadius.only(
          bottomLeft: Radius.circular(10),
          bottomRight: Radius.circular(10)),
      boxShadow: [
        BoxShadow(
            color: Color(0xffA22447).withOpacity(.05),
            offset: Offset(0, 0),
            blurRadius: 20,
            spreadRadius: 3)
      ]),
  child: Material(
    borderRadius: BorderRadius.only(
        bottomLeft: Radius.circular(10),
        bottomRight: Radius.circular(10)),
    elevation: 5,
    shadowColor: Color(0xffA22447).withOpacity(.05),
    color: Color(0xFFF7F7F7),
    child: SizedBox(
      height: MediaQuery.of(context).size.height / 3,
    ),
  ),
)

System has not been booted with systemd as init system (PID 1). Can't operate

I had this problem running WSL 2

the solution was the command

 $ sudo dockerd

if after that you still have a problem with permission, run the command:

 $ sudo usermod -aG docker your-user

DeprecationWarning: Buffer() is deprecated due to security and usability issues when I move my script to another server

The use of the deprecated new Buffer() constructor (i.E. as used by Yarn) can cause deprecation warnings. Therefore one should NOT use the deprecated/unsafe Buffer constructor.

According to the deprecation warning new Buffer() should be replaced with one of:

  • Buffer.alloc()
  • Buffer.allocUnsafe() or
  • Buffer.from()

Another option in order to avoid this issue would be using the safe-buffer package instead.

You can also try (when using yarn..):

yarn global add yarn

as mentioned here: Link

Another suggestion from the comments (thx to gkiely): self-update

Note: self-update is not available. See policies for enforcing versions within a project

In order to update your version of Yarn, run

curl --compressed -o- -L https://yarnpkg.com/install.sh | bash

Starting ssh-agent on Windows 10 fails: "unable to start ssh-agent service, error :1058"

Yeah, as others have suggested, this error seems to mean that ssh-agent is installed but its service (on windows) hasn't been started.

You can check this by running in Windows PowerShell:

> Get-Service ssh-agent

And then check the output of status is not running.

Status   Name               DisplayName
------   ----               -----------
Stopped  ssh-agent          OpenSSH Authentication Agent

Then check that the service has been disabled by running

> Get-Service ssh-agent | Select StartType

StartType
---------
Disabled

I suggest setting the service to start manually. This means that as soon as you run ssh-agent, it'll start the service. You can do this through the Services GUI or you can run the command in admin mode:

 > Get-Service -Name ssh-agent | Set-Service -StartupType Manual

Alternatively, you can set it through the GUI if you prefer.

services.msc showing the properties of the OpenSSH Agent

Getting all documents from one collection in Firestore

if you want include Id

async getMarkers() {
  const events = await firebase.firestore().collection('events')
  events.get().then((querySnapshot) => {
      const tempDoc = querySnapshot.docs.map((doc) => {
        return { id: doc.id, ...doc.data() }
      })
      console.log(tempDoc)
    })
}

Same way with array

async getMarkers() {
  const events = await firebase.firestore().collection('events')
  events.get().then((querySnapshot) => {
      const tempDoc = []
      querySnapshot.forEach((doc) => {
         tempDoc.push({ id: doc.id, ...doc.data() })
      })
      console.log(tempDoc)
   })
 }

Flutter - The method was called on null

Because of your initialization wrong.

Don't do like this,

MethodName _methodName;

Do like this,

MethodName _methodName = MethodName();

Can I use library that used android support with Androidx projects.

I added below two lines in gradle.properties file

android.useAndroidX=true
android.enableJetifier=true

then I got the following error

error: package android.support.v7.app does not exist
import android.support.v7.app.AlertDialog;
                         ^
                         

I have removed the imports and added below line

import static android.app.AlertDialog.*;

And the classes which are extended from AppCompactActivity, added the below line. (For these errors you just need to press alt+enter in android studio which will import the correct library for you. Like this you can resolve all the errors)

import androidx.appcompat.app.AppCompatActivity;

In your xml file if you have used any

<android.support.v7.widget.Toolbar 

replace it with androidx.appcompat.widget.Toolbar

then in your java code

import androidx.appcompat.widget.Toolbar;

Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'

in my experience. I was using jsp for web. at that time I use mysql 5 and mysql connecter jar 8. So due to the version problem I face this kind of problem. I solve by replace the mysql connector jar file the exact version mysql.

ERROR Error: Uncaught (in promise), Cannot match any routes. URL Segment

As the error says your router link should match the existing routes configured

It should be just routerLink="/about"

How to convert string to boolean in typescript Angular 4

Define extension: String+Extension.ts

interface String {
  toBoolean(): boolean
}

String.prototype.toBoolean = function (): boolean {
  switch (this) {
    case 'true':
    case '1':
    case 'on':
    case 'yes':
      return true
    default:
      return false
  }
}

And import in any file where you want to use it '@/path/to/String+Extension'

What is the Record type in typescript?

  1. Can someone give a simple definition of what Record is?

A Record<K, T> is an object type whose property keys are K and whose property values are T. That is, keyof Record<K, T> is equivalent to K, and Record<K, T>[K] is (basically) equivalent to T.

  1. Is Record<K,T> merely a way of saying "all properties on this object will have type T"? Probably not all objects, since K has some purpose...

As you note, K has a purpose... to limit the property keys to particular values. If you want to accept all possible string-valued keys, you could do something like Record<string, T>, but the idiomatic way of doing that is to use an index signature like { [k: string]: T }.

  1. Does the K generic forbid additional keys on the object that are not K, or does it allow them and just indicate that their properties are not transformed to T?

It doesn't exactly "forbid" additional keys: after all, a value is generally allowed to have properties not explicitly mentioned in its type... but it wouldn't recognize that such properties exist:

declare const x: Record<"a", string>;
x.b; // error, Property 'b' does not exist on type 'Record<"a", string>'

and it would treat them as excess properties which are sometimes rejected:

declare function acceptR(x: Record<"a", string>): void;
acceptR({a: "hey", b: "you"}); // error, Object literal may only specify known properties

and sometimes accepted:

const y = {a: "hey", b: "you"};
acceptR(y); // okay
  1. With the given example:

    type ThreeStringProps = Record<'prop1' | 'prop2' | 'prop3', string>
    

    Is it exactly the same as this?:

    type ThreeStringProps = {prop1: string, prop2: string, prop3: string}
    

Yes!

Hope that helps. Good luck!

Flutter- wrapping text

Use Expanded

 Expanded(
            child: new Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: <Widget>[
                new Text(_name, style: Theme.of(context).textTheme.subhead),
                new Container(
                  margin: const EdgeInsets.only(top: 5.0),
                  child: new Text(text),
                ),
              ],
            ),

Iterating over arrays in Python 3

You can use

    nditer

Here I calculated no. of positive and negative coefficients in a logistic regression:

b=sentiment_model.coef_
pos_coef=0
neg_coef=0
for i in np.nditer(b):
    if i>0:
    pos_coef=pos_coef+1
    else:
    neg_coef=neg_coef+1
print("no. of positive coefficients is : {}".format(pos_coef))
print("no. of negative coefficients is : {}".format(neg_coef))

Output:

no. of positive coefficients is : 85035
no. of negative coefficients is : 36199

Could not install packages due to an EnvironmentError: [WinError 5] Access is denied:

This is how I solved this issue.

downgrade to python 3.6.x 64bit. I installed3.6.8 64bit.

install virtualenv by pip install virtualenv

upgrade pip to the latest version, for me it’s 19.3

go to the folder you want to create a virtual environment and type virtualenv ENV after created the virtual environment, go to the subfolder \PATH\ENV\Script and execute activate.bat. Now you will be in the virtual environment.

pip install rasa The problem is tensorflow 15 requires 64 bit python with no more than 3.6

How to allow all Network connection types HTTP and HTTPS in Android (9) Pie?

Easy Way

Add usesCleartextTraffic to AndroidManifest.xml

<application
...
android:usesCleartextTraffic="true"
...>

Indicates whether the app intends to use cleartext network traffic, such as cleartext HTTP. The default value for apps that target API level 27 or lower is "true". Apps that target API level 28 or higher default to "false".

Flutter plugin not installed error;. When running flutter doctor

When you execute the flutter doctor command it checks your environment and displays a report to the terminal window. In your case it seems that you did not install the dart and flutter plugin to be able to use them in Android Studio.

To install a plugin, click on Files>Settings>Plugins>install jetbrain plugins

The plugins will add new functionalities to android studio related to flutter. Example it will add the flutter inspector, outliner.

The SDK that you added to the path, will be needed when creating a new flutter project.

enter image description here

How do I install opencv using pip?

  1. Open anaconda command prompt and type in below command.

    conda install -c conda-forge opencv

  2. Once the 'Solving environment' is done. It will ask to download dependencies. Type 'y'.

  3. It will install all the dependencies and then you are ready to code.

Android Material and appcompat Manifest merger failed

change your build.gradle dependencies into

 implementation 'com.android.support:appcompat-v7:28.0.0-alpha3'

or

 implementation 'com.android.support:appcompat-v7:28.0.0-alpha1'

How to scroll page in flutter

you can scroll any part of content in two ways ...

  1. you can use the list view directly
  2. or SingleChildScrollView

most of the time i use List view directly when ever there is a keybord intraction in that specific screen so that the content dont get overlap by the keyboard and more over scrolls to top ....

this trick will be helpful many a times....

Find the smallest positive integer that does not occur in a given sequence

The below C++ solution obtained a 100% score. The theoretical complexity of the code is. Time Complexity : O(N) amortized due to hash set and Auxiliary Space complexity of O(N) due to use of hash for lookup in O(1) time.

#include<iostream>
#include<string>
#include<vector>
#include<climits>
#include<cmath>
#include<unordered_set>

using namespace std;

int solution(vector<int>& A)
{
  if(!A.size())
    return(1);

  unordered_set<int> hashSet;
  int maxItem=INT_MIN;
  for(const auto& item : A)
  {
    hashSet.insert(item);
    if(maxItem<item)
      maxItem=item;
  }

  if(maxItem<1)
    return(1);

  for(int i=1;i<=maxItem;++i)
  {
    if(hashSet.find(i)==hashSet.end())
      return(i);
  }
  return(maxItem+1);
}

Select Specific Columns from Spark DataFrame

If you want to split you dataframe into two different ones, do two selects on it with the different columns you want.

 val sourceDf = spark.read.csv(...)
 val df1 = sourceDF.select("first column", "second column", "third column")
 val df2 = sourceDF.select("first column", "second column", "third column")

Note that this of course means that the sourceDf would be evaluated twice, so if it can fit into distributed memory and you use most of the columns across both dataframes it might be a good idea to cache it. It it has many extra columns that you don't need, then you can do a select on it first to select on the columns you will need so it would store all that extra data in memory.

Angular: How to download a file from HttpClient?

I ended up here when searching for ”rxjs download file using post”.

This was my final product. It uses the file name and type given in the server response.

import { ajax, AjaxResponse } from 'rxjs/ajax';
import { map } from 'rxjs/operators';

downloadPost(url: string, data: any) {
    return ajax({
        url: url,
        method: 'POST',
        responseType: 'blob',
        body: data,
        headers: {
            'Content-Type': 'application/json',
            'Accept': 'text/plain, */*',
            'Cache-Control': 'no-cache',
        }
    }).pipe(
        map(handleDownloadSuccess),
    );
}


handleDownloadSuccess(response: AjaxResponse) {
    const downloadLink = document.createElement('a');
    downloadLink.href = window.URL.createObjectURL(response.response);

    const disposition = response.xhr.getResponseHeader('Content-Disposition');
    if (disposition) {
        const filenameRegex = /filename[^;=\n]*=((['"]).*?\2|[^;\n]*)/;
        const matches = filenameRegex.exec(disposition);
        if (matches != null && matches[1]) {
            const filename = matches[1].replace(/['"]/g, '');
            downloadLink.setAttribute('download', filename);
        }
    }

    document.body.appendChild(downloadLink);
    downloadLink.click();
    document.body.removeChild(downloadLink);
}

Waiting for another flutter command to release the startup lock

This occurs when any other flutter command is running in background. To solve this you can run for mac

killall -9 dart

and for windows open task manager. Then in processes tab, search for dart process and kill all of them. Hope this helps you.

Has been blocked by CORS policy: Response to preflight request doesn’t pass access control check

Angular and Django Rest Framework.

I encountered similar error while making post request to my DRF api. It happened that all I was missing was trailing slash for endpoint.

Xcode 10.2.1 Command PhaseScriptExecution failed with a nonzero exit code

Another reason for the error might be is that Xcode is running a script during the run phase.

If this is the case, you have 2 options:

  1. Delete the script (makes sense if the script is NOT important)

  2. Modify/update the scripts location path (Xcode might not be able to locate the script)

Run Phase Script

In my case, the script was important, so I modified/updated its location.

Originally, the script location path was written like this:

$SRCROOT/scripts/clean-assets.sh

Because the scripts path contained spaces (I moved the project to a new directory), I changed the path to this:

"$SRCROOT"/scripts/clean-assets.sh

By adding quotes to SRCROOT, changing it to "$SRCROOT", the error will go away.

FATAL ERROR: Ineffective mark-compacts near heap limit Allocation failed - JavaScript heap out of memory in ionic 3

For me, the issue was having an extra node_modules folder that I renamed to node_modules_old and running an npm install to generate a fresh node_modules. Somehow the build must have still been picking up the node_modules_old folder, so I moved node_modules_old out of the directory to fix the issue.

How can I force component to re-render with hooks in React?

This will render depending components 3 times (arrays with equal elements aren't equal):

const [msg, setMsg] = useState([""])

setMsg(["test"])
setMsg(["test"])
setMsg(["test"])

What is the meaning of "Failed building wheel for X" in pip install?

I got the same message when I tried to install pip install django-imagekit. So I ran pip install wheel (I had python 2.7) and then I reran pip install django-imagekit and it worked. Thanks

No Creators, like default construct, exist): cannot deserialize from Object value (no delegate- or property-based Creator

Encountered the same error in below Usecase.

I tried to hit the Rest(Put mapping) end point using sprint boot(2.0.0 Snapshot Version) without having default constructor in respective bean.

But with latest Spring Boot versions(2.4.1 Version) the same piece of code is working without error.

so the bean default constructor is no longer needed in latest version of Spring Boot

What is useState() in React?

useState is one of the hooks available in React v16.8.0. It basically lets you turn your otherwise non-stateful/functional components to one that can have its own state.

At the very basic level, it's used this way:

const [isLoading, setLoading] = useState(true);

This then lets you call setLoading passing a boolean value. It's a cool way of having "stateful" functional component.

Set the space between Elements in Row Flutter

Removing Space-:

new Row(
            mainAxisAlignment: MainAxisAlignment.center,
            children: <Widget>[
              GestureDetector(
                child: new Text('Don\'t have an account?',
                    style: new TextStyle(color: Color(0xFF2E3233))),
                onTap: () {},
              ),
              GestureDetector(
                onTap: (){},
                  child: new Text(
                'Register.',
                style: new TextStyle(
                    color: Color(0xFF84A2AF), fontWeight: FontWeight.bold),
              ))
            ],
          ),

OR

GestureDetector(
            onTap: (){},
            child: new Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: <Widget>[
                new Text('Don\'t have an account?',
                    style: new TextStyle(color: Color(0xFF2E3233))),
                new Text(
                  'Register.',
                  style: new TextStyle(
                  color: Color(0xFF84A2AF), fontWeight: FontWeight.bold),
                )
              ],
            ),
          ),

A fatal error occurred while creating a TLS client credential. The internal error state is 10013

I found this here: https://port135.com/schannel-the-internal-error-state-is-10013-solved/

"Correct file permissions Correct the permissions on the c:\ProgramData\Microsoft\Crypto\RSA\MachineKeys folder:

Everyone Access: Special Applies to 'This folder only' Network Service Access: Read & Execute Applies to 'This folder, subfolders and files' Administrators Access: Full Control Applies to 'This folder, subfolder and files' System Access: Full control Applies to 'This folder, subfolder and Files' IUSR Access: Full Control Applies to 'This folder, subfolder and files' The internal error state is 10013 After these changes, restart the server. The 10013 errors should disappear."

How to call loading function with React useEffect only once

we developed a module on GitHub that has hooks for fetching data so you can use it like this for your purpose:

import { useFetching } from "react-concurrent";

const app = () => {
  const { data, isLoading, error , refetch } = useFetching(() =>
    fetch("http://example.com"),
  );
};

You can fork that out, but any PRs are welcome. https://github.com/hosseinmd/react-concurrent#react-concurrent

Angular CLI Error: The serve command requires to be run in an Angular project, but a project definition could not be found

Solved. I was getting same issue on ubuntu 18.04.01 LTS. No above options worked as I was using NVM (Node Version manager.) Solution is
before creating project,use command
nvm use 10
(my node version was 10.15.0, so I used "nvm use 10")
It will show you output-
Now using node v10.15.0 (npm v6.4.1)
Versions will vary as per individual systems. then create new project.

Selenium: WebDriverException:Chrome failed to start: crashed as google-chrome is no longer running so ChromeDriver is assuming that Chrome has crashed

I encountered the exact problem running on docker container (in build environment). After ssh into the container, I tried running the test manually and still encountered

(unknown error: DevToolsActivePort file doesn't exist)
     (The process started from chrome location /usr/bin/google-chrome-stable is 
      no longer running, so ChromeDriver is assuming that Chrome has crashed.)

When I tried running chrome locally /usr/bin/google-chrome-stable, error message

Running as root without --no-sandbox is not supported

I checked my ChromeOptions and it was missing --no-sandbox, which is why it couldn't spawn chrome.

capabilities = Selenium::WebDriver::Remote::Capabilities.chrome(
  chromeOptions: { args: %w(headless --no-sandbox disable-gpu window-size=1920,1080) }
)

must declare a named package eclipse because this compilation unit is associated to the named module

The "delete module-info.java at your Project Explorer tab" answer is the easiest and most straightforward answer, but

for those who would want a little more understanding or control of what's happening, the following alternate methods may be desirable;

  • make an ever so slightly more realistic application; com.YourCompany.etc or just com.HelloWorld (Project name: com.HelloWorld and class name: HelloWorld)

or

  • when creating the java project; when in the Create Java Project dialog, don't choose Finish but Next, and deselect Create module-info.java file

How to set width of mat-table column in angular?

Here's an alternative way of tackling the problem:

Instead of trying to "fix it in post" why don't you truncate the description before the table needs to try and fit it into its columns? I did it like this:

<ng-container matColumnDef="description">
   <th mat-header-cell *matHeaderCellDef> {{ 'Parts.description' | translate }} </th>
            <td mat-cell *matCellDef="let element">
                {{(element.description.length > 80) ? ((element.description).slice(0, 80) + '...') : element.description}}
   </td>
</ng-container>

So I first check if the array is bigger than a certain length, if Yes then truncate and add '...' otherwise pass the value as is. This enables us to still benefit from the auto-spacing the table does :)

enter image description here

expected assignment or function call: no-unused-expressions ReactJS

In my case I had curly braces where it should have been parentheses.

const Button = () => {
    <button>Hello world</button>
}

Where it should have been:

const Button = () => (
    <button>Hello world</button>
)

The reason for this, as explained in the MDN Docs is that an arrow function wrapped by () will return the value it wraps, so if I wanted to use curly braces I had to add the return keyword, like so:

const Button = () => {
    return <button>Hello world</button>
}

ImageMagick security policy 'PDF' blocking conversion

Well, I added

  <policy domain="coder" rights="read | write" pattern="PDF" />

just before </policymap> in /etc/ImageMagick-7/policy.xml and that makes it work again, but not sure about the security implications of that.

Could not install packages due to an EnvironmentError: [Errno 13]

This also happens to me when I try to install the opencv-python package:

installation attempt

I can fix it with command line

python3 -m pip install {name of package} --user

When I try to install the said package, the command becomes:

python3 -m pip install opencv-python --user

Resulting in this:

result

Flutter: RenderBox was not laid out

Reading answers here, it seems that the error "RenderBox was not laid out" is caused when somehow the ListView size is limitless and this can happen in different scenarios.

Just aiming to help who may have the same case as mine. In my case, I was getting this error because my ListView was inside a a column whose parent was a SingleChildScrollView. I remove this parent and it worked.

Here is my working code:

 List _todoList = ["AAA", "BBB"];

 ...

    body: Column(
      children: [
        Container(...),
        Expanded(
            child: ListView.builder(
                itemCount: _todoList.length,
                itemBuilder: (context, index) {
                  return ListTile(title: Text(_todoList[index]));
                }))
      ],
    ));

Here how it was when I was getting the "not laid out" error:

     List _todoList = ["AAA", "BBB"];

     ...


     body: SingleChildScrollView(child: Column(
      children: [
        Container(...),
        Expanded(
            child: ListView.builder(
                itemCount: _todoList.length,
                itemBuilder: (context, index) {
                  return ListTile(title: Text(_todoList[index]));
                }))
      ],
    )));

I hope this may be useful for someone.

Space between Column's children in Flutter

You can also use a helper function to add spacing after each child.

List<Widget> childrenWithSpacing({
  @required List<Widget> children,
  double spacing = 8,
}) {
  final space = Container(width: spacing, height: spacing);
  return children.expand((widget) => [widget, space]).toList();
}

So then, the returned list may be used as a children of a column

Column(
  children: childrenWithSpacing(
    spacing: 14,
    children: [
      Text('This becomes a text with an adjacent spacing'),
      if (true == true) Text('Also, makes it easy to add conditional widgets'),
    ],
  ),
);

I'm not sure though if it's wrong or have a performance penalty to run the children through a helper function for the same goal?

WebView showing ERR_CLEARTEXT_NOT_PERMITTED although site is HTTPS

When you call "https://darkorbit.com/" your server figures that it's missing "www" so it redirects the call to "http://www.darkorbit.com/" and then to "https://www.darkorbit.com/", your WebView call is blocked at the first redirection as it's a "http" call. You can call "https://www.darkorbit.com/" instead and it will solve the issue.

OpenCV !_src.empty() in function 'cvtColor' error

If anyone is experiencing this same problem when reading a frame from a webcam [with code similar to "frame = cv2.VideoCapture(0)"] and work in Jupyter Notebook, you may try:

  1. ensure previously tried code is not running already and restart Jupyter Notebook kernel

  2. SEPARATE code "frame = cv2.VideoCapture(0)" in separate cell on place where it is [previous code put in cell above, code under put to cell down]

  3. then run all the code above cell where is "frame = cv2.VideoCapture(0)"

  4. then try run next cell with its only code "frame = cv2.VideoCapture(0)" - AND - till you will continue in executing other cells - ENSURE - that ASTERIX on the left side of this particular cell DISAPEAR and command order number appear instead - only then continue

  5. now you can try execute the rest of your code as your camera input should not be empty anymore :-)

  6. After end, ensure you close all your program and restart kernel to prepare it for another run

ConvergenceWarning: Liblinear failed to converge, increase the number of iterations

Explicitly specifying the max_iter resolves the warning as the default max_iter is 100. [For Logistic Regression].

 logreg = LogisticRegression(max_iter=1000)

pod has unbound PersistentVolumeClaims

You have to define a PersistentVolume providing disc space to be consumed by the PersistentVolumeClaim.

When using storageClass Kubernetes is going to enable "Dynamic Volume Provisioning" which is not working with the local file system.


To solve your issue:

  • Provide a PersistentVolume fulfilling the constraints of the claim (a size >= 100Mi)
  • Remove the storageClass-line from the PersistentVolumeClaim
  • Remove the StorageClass from your cluster

How do these pieces play together?

At creation of the deployment state-description it is usually known which kind (amount, speed, ...) of storage that application will need.
To make a deployment versatile you'd like to avoid a hard dependency on storage. Kubernetes' volume-abstraction allows you to provide and consume storage in a standardized way.

The PersistentVolumeClaim is used to provide a storage-constraint alongside the deployment of an application.

The PersistentVolume offers cluster-wide volume-instances ready to be consumed ("bound"). One PersistentVolume will be bound to one claim. But since multiple instances of that claim may be run on multiple nodes, that volume may be accessed by multiple nodes.

A PersistentVolume without StorageClass is considered to be static.

"Dynamic Volume Provisioning" alongside with a StorageClass allows the cluster to provision PersistentVolumes on demand. In order to make that work, the given storage provider must support provisioning - this allows the cluster to request the provisioning of a "new" PersistentVolume when an unsatisfied PersistentVolumeClaim pops up.


Example PersistentVolume

In order to find how to specify things you're best advised to take a look at the API for your Kubernetes version, so the following example is build from the API-Reference of K8S 1.17:

apiVersion: v1
kind: PersistentVolume
metadata:
  name: ckan-pv-home
  labels:
    type: local
spec:
  capacity:
    storage: 100Mi
  hostPath:
    path: "/mnt/data/ckan"

The PersistentVolumeSpec allows us to define multiple attributes. I chose a hostPath volume which maps a local directory as content for the volume. The capacity allows the resource scheduler to recognize this volume as applicable in terms of resource needs.


Additional Resources:

How to downgrade python from 3.7 to 3.6

create a virtual environment, install then switch to python 3.6.5

$ conda create -n tensorflow python=3.7
$ conda activate tensorflow
$ conda install python=3.6.5
$ pip install tensorflow

activate the environment when you would want to use tensorflow

Post request in Laravel - Error - 419 Sorry, your session/ 419 your page has expired

Before reading below make sure you have @csrf or {{ csrf_field() }} in your form like

<form method="post">
@csrf <!-- {{ csrf_field() }} -->
... rest of form ...
</form>

The Session Expired or 419 Page Expired error message in larvel comes up because somewhere your csrf token verification fails which means the App\Http\Middleware\VerifyCsrfToken::class middleware is already turned on. In the form the @csrf blade directive is already added, which should be fine as well.

Then the other area to check is the session. The csrf token verification is directly involved with your session, So you might want to check whether your session driver is working or not, such as an incorrectly configured Redis might cause an issue.

Maybe you can try switching your session driver/software from your .env file, the supported drivers are given below

Supported Session drivers in Laravel 5, Laravel 6 and Laravel 7 (Doc Link)

  • file - sessions are stored in storage/framework/sessions.
  • cookie - sessions are stored in secure, encrypted cookies.
  • database - sessions are stored in a relational database.
  • memcached / redis - sessions are stored in one of these fast, cache based stores.
  • array - sessions are stored in a PHP array and will not be persisted.

If your form works after switching the session driver, then something wrong is with that particular driver, try to fix the error from there.

Possible error-prone scenarios

  • Probably file-based sessions might not work because of the permission issues with the /storage directory (a quick googling will fetch you the solution), also remember putting 777 for the directory is never the solution.

  • In the case of the database driver, your DB connection might be wrong, or the sessions table might not exist or wrongly configured (the wrong configuration part was confirmed to be an issue as per the comment by @Junaid Qadir).

  • redis/memcached configuration is wrong or is being manipulated by some other piece of code in the system at the same time.

It might be a good idea to execute php artisan key:generate and generate a new app key which will, in turn, flush the session data.

Clear Browser Cache HARD, I found chrome and firefox being a culprit more than I can remember.

Read more about why application keys are important

How do I install Java on Mac OSX allowing version switching?

You can use asdf to install and switch between multiple java versions. It has plugins for other languages as well. You can install asdf with Homebrew

brew install asdf

When asdf is configured, install java plugin

asdf plugin-add java

Pick a version to install

asdf list-all java

For example to install and configure adoptopenjdk8

asdf install java adoptopenjdk-8.0.272+10
asdf global java adoptopenjdk-8.0.272+10

And finally if needed, configure JAVA_HOME for your shell. Just add to your shell init script such as ~/.zshrc in case of zsh:

. ~/.asdf/plugins/java/set-java-home.zsh

Git is not working after macOS Update (xcrun: error: invalid active developer path (/Library/Developer/CommandLineTools)

If you created a new Applications folder in an external drive and installed Xcode there:

sudo xcode-select --switch /Volumes/MyExternalStorageName/Applications/Xcode.app/Contents/Developer

How to install OpenJDK 11 on Windows?

AdoptOpenJDK is a new website hosted by the java community. You can find .msi installers for OpenJDK 8 through 14 there, which will perform all the things listed in the question (Unpacking, registry keys, PATH variable updating (and JAVA_HOME), uninstaller...).

Can't compile C program on a Mac after upgrade to Mojave

The problem is that Xcode, especially Xcode 10.x, has not installed everything, so ensure the command line tools are installed, type this in a terminal shell:

xcode-select --install

also start Xcode and ensure all the required installation is installed ( you should get prompted if it is not.) and since Xcode 10 does not install the full Mac OS SDK, run the installer at

/Library/Developer/CommandLineTools/Packages/macOS_SDK_headers_for_macOS_10.14.pkg

as this package is not installed by Xcode 10.

How to install JDK 11 under Ubuntu?

To install Openjdk 11 in Ubuntu, the following commands worked well.

sudo add-apt-repository ppa:openjdk-r/ppa
sudo apt-get update
sudo apt install openjdk-11-jdk

Java 11 package javax.xml.bind does not exist

According to the release-notes, Java 11 removed the Java EE modules:

java.xml.bind (JAXB) - REMOVED
  • Java 8 - OK
  • Java 9 - DEPRECATED
  • Java 10 - DEPRECATED
  • Java 11 - REMOVED

See JEP 320 for more info.

You can fix the issue by using alternate versions of the Java EE technologies. Simply add Maven dependencies that contain the classes you need:

<dependency>
  <groupId>javax.xml.bind</groupId>
  <artifactId>jaxb-api</artifactId>
  <version>2.3.0</version>
</dependency>
<dependency>
  <groupId>com.sun.xml.bind</groupId>
  <artifactId>jaxb-core</artifactId>
  <version>2.3.0</version>
</dependency>
<dependency>
  <groupId>com.sun.xml.bind</groupId>
  <artifactId>jaxb-impl</artifactId>
  <version>2.3.0</version>
</dependency>

Jakarta EE 8 update (Mar 2020)

Instead of using old JAXB modules you can fix the issue by using Jakarta XML Binding from Jakarta EE 8:

<dependency>
  <groupId>jakarta.xml.bind</groupId>
  <artifactId>jakarta.xml.bind-api</artifactId>
  <version>2.3.3</version>
</dependency>
<dependency>
  <groupId>com.sun.xml.bind</groupId>
  <artifactId>jaxb-impl</artifactId>
  <version>2.3.3</version>
  <scope>runtime</scope>
</dependency>

Jakarta EE 9 update (Nov 2020)

Use latest release of Eclipse Implementation of JAXB 3.0.0:

<dependency>
  <groupId>jakarta.xml.bind</groupId>
  <artifactId>jakarta.xml.bind-api</artifactId>
  <version>3.0.0</version>
</dependency>
<dependency>
  <groupId>com.sun.xml.bind</groupId>
  <artifactId>jaxb-impl</artifactId>
  <version>3.0.0</version>
  <scope>runtime</scope>
</dependency>

Note: Jakarta EE 9 adopts new API package namespace jakarta.xml.bind.*, so update import statements:

javax.xml.bind -> jakarta.xml.bind

How to change status bar color in Flutter?

Instead of the often suggested SystemChrome.setSystemUIOverlayStyle() which is a system wide service and does not reset on a different route, you can use an AnnotatedRegion<SystemUiOverlayStyle> which is a widget and only has effect for the widget that you wrap.

AnnotatedRegion<SystemUiOverlayStyle>(
   value: SystemUiOverlayStyle(
      statusBarColor: Colors.white,
  ),
  child: Scaffold(
      ...
  ),
)

WARNING: API 'variant.getJavaCompile()' is obsolete and has been replaced with 'variant.getJavaCompileProvider()'

Migrate your project to androidX.

dependencies are upgraded to androidX. so if you want to use androidX contents migrate your project to androidX.

With Android Studio 3.2 and higher, you can quickly migrate an existing project to use AndroidX by selecting Refactor > Migrate to AndroidX from the menu bar.

Downgrading dependencies may fix your problem this time - but not recommended

IntelliJ can't recognize JavaFX 11 with OpenJDK 11

As mentioned in the comments, the Starting Guide is the place to start with Java 11 and JavaFX 11.

The key to work as you did before Java 11 is to understand that:

  • JavaFX 11 is not part of the JDK anymore
  • You can get it in different flavors, either as an SDK or as regular dependencies (maven/gradle).
  • You will need to include it to the module path of your project, even if your project is not modular.

JavaFX project

If you create a regular JavaFX default project in IntelliJ (without Maven or Gradle) I'd suggest you download the SDK from here. Note that there are jmods as well, but for a non modular project the SDK is preferred.

These are the easy steps to run the default project:

  1. Create a JavaFX project
  2. Set JDK 11 (point to your local Java 11 version)
  3. Add the JavaFX 11 SDK as a library. The URL could be something like /Users/<user>/Downloads/javafx-sdk-11/lib/. Once you do this you will notice that the JavaFX classes are now recognized in the editor.

JavaFX 11 Project

  1. Before you run the default project, you just need to add these to the VM options:

    --module-path /Users/<user>/Downloads/javafx-sdk-11/lib --add-modules=javafx.controls,javafx.fxml

  2. Run

Maven

If you use Maven to build your project, follow these steps:

  1. Create a Maven project with JavaFX archetype
  2. Set JDK 11 (point to your local Java 11 version)
  3. Add the JavaFX 11 dependencies.

    <dependencies>
        <dependency>
            <groupId>org.openjfx</groupId>
            <artifactId>javafx-controls</artifactId>
            <version>11</version>
        </dependency>
        <dependency>
            <groupId>org.openjfx</groupId>
            <artifactId>javafx-fxml</artifactId>
            <version>11</version>
        </dependency>
    </dependencies>
    

Once you do this you will notice that the JavaFX classes are now recognized in the editor.

JavaFX 11 Maven project

You will notice that Maven manages the required dependencies for you: it will add javafx.base and javafx.graphics for javafx.controls, but most important, it will add the required classifier based on your platform. In my case, Mac.

This is why your jars org.openjfx:javafx-controls:11 are empty, because there are three possible classifiers (windows, linux and mac platforms), that contain all the classes and the native implementation.

In case you still want to go to your .m2 repo and take the dependencies from there manually, make sure you pick the right one (for instance .m2/repository/org/openjfx/javafx-controls/11/javafx-controls-11-mac.jar)

  1. Replace default maven plugins with those from here.

  2. Run mvn compile javafx:run, and it should work.

Similar works as well for Gradle projects, as explained in detail here.

EDIT

The mentioned Getting Started guide contains updated documentation and sample projects for IntelliJ:

Difference between OpenJDK and Adoptium/AdoptOpenJDK

Update: AdoptOpenJDK has changed its name to Adoptium, as part of its move to the Eclipse Foundation.


OpenJDK ? source code
Adoptium/AdoptOpenJDK ? builds

Difference between OpenJDK and AdoptOpenJDK

The first provides source-code, the other provides builds of that source-code.

Several vendors of Java & OpenJDK

Adoptium of the Eclipse Foundation, formerly known as AdoptOpenJDK, is only one of several vendors distributing implementations of the Java platform. These include:

  • Eclipse Foundation (Adoptium/AdoptOpenJDK)
  • Azul Systems
  • Oracle
  • Red Hat / IBM
  • BellSoft
  • SAP
  • Amazon AWS
  • … and more

See this flowchart of mine to help guide you in picking a vendor for an implementation of the Java platform. Click/tap to zoom.

Flowchart guiding you in choosing a vendor for a Java 11 implementation

Another resource: This comparison matrix by Azul Systems is useful, and seems true and fair to my mind.

Here is a list of considerations and motivations to consider in choosing a vendor and implementation.

Motivations in choosing a vendor for Java

Some vendors offer you a choice of JIT technologies.

Diagram showing history of HotSpot & JRockit merging, and OpenJ9 both available in AdoptOpenJDK

To understand more about this Java ecosystem, read Java Is Still Free

Objects are not valid as a React child. If you meant to render a collection of children, use an array instead

Just to add to the other options, I was trying to access a nested object within the main object through the dot method as in: this.state.arrayData.CompleteAdress.Location In this case Location is a nested object inside Complete address which is why i cant simply access it with the dot notation.

  • So if you're facing this same issue, try JSON.parse so that you access the nested object and then manipulate accordingly.

Xcode 10: A valid provisioning profile for this executable was not found

Finally, I figured out what's going on... almost take me 2 hours

My case is, my phone's date is not correct. I forgot I changed my phone's date. I guess that makes all of my provisioning profiles expired...

So if you've tried all of those answers but nothing works. Go to the SETTINGS, check your phone's date.

What is "not assignable to parameter of type never" error in typescript?

All you have to do is define your result as a string array, like the following:

const result : string[] = [];

Without defining the array type, it by default will be never. So when you tried to add a string to it, it was a type mismatch, and so it threw the error you saw.

Xcode 10, Command CodeSign failed with a nonzero exit code

I tried all of the above soloutions. none of them worked. I figured out that I had 2 keychains. Both of them had certificates and keys. I´ve deleted one keychain and removed all its key and certificates and just kept the "login" keychain. I´ve also removed everything from this keychain and then redownloaded the certificate from the apple developer page. After doing so everything was imported just into this ONE keychain. Cleaned Xcode, started. no problems!

Receiving "Attempted import error:" in react app

import { combineReducers } from '../../store/reducers';

should be

import combineReducers from '../../store/reducers';

since it's a default export, and not a named export.

There's a good breakdown of the differences between the two here.

JS file gets a net::ERR_ABORTED 404 (Not Found)

As mentionned in comments: you need a way to send your static files to the client. This can be achieved with a reverse proxy like Nginx, or simply using express.static().

Put all your "static" (css, js, images) files in a folder dedicated to it, different from where you put your "views" (html files in your case). I'll call it static for the example. Once it's done, add this line in your server code:

app.use("/static", express.static('./static/'));

This will effectively serve every file in your "static" folder via the /static route.

Querying your index.js file in the client thus becomes:

<script src="static/index.js"></script>

React Hooks useState() with Object

Thanks Philip this helped me - my use case was I had a form with lot of input fields so I maintained initial state as object and I was not able to update the object state.The above post helped me :)

const [projectGroupDetails, setProjectGroupDetails] = useState({
    "projectGroupId": "",
    "projectGroup": "DDD",
    "project-id": "",
    "appd-ui": "",
    "appd-node": ""    
});

const inputGroupChangeHandler = (event) => {
    setProjectGroupDetails((prevState) => ({
       ...prevState,
       [event.target.id]: event.target.value
    }));
}

<Input 
    id="projectGroupId" 
    labelText="Project Group Id" 
    value={projectGroupDetails.projectGroupId} 
    onChange={inputGroupChangeHandler} 
/>


Error: Java: invalid target release: 11 - IntelliJ IDEA

January 6th, 2021

This is what worked for me.

Go to File -> Project Structure and select the "Dependencies" tab on the right panel of the window. Then change the "Module SDK" using the drop-down like this. Then apply changes.

image 1

Requests (Caused by SSLError("Can't connect to HTTPS URL because the SSL module is not available.") Error in PyCharm requesting website

Don't know if this has been solved yet but I was getting similar problems with Anaconda python 3.7.3 and Idle on Windows 10. Fixed it by adding:

<path>\Anaconda3
<path>\Anaconda3\scripts
<path>\Anaconda3\Library\bin

to the PATH variable.

How to fix 'Unchecked runtime.lastError: The message port closed before a response was received' chrome issue?

Looks like the NoCoffee Vision Simulator extension for Chrome will also cause this error. Just adding it as a prospective cause for people looking in their own instance.

How to setup virtual environment for Python in VS Code?

There is a VSCode extension called "Python Auto Venv" that automatically detects and uses your virtual environment if there is one.

useState set method not reflecting change immediately

I just finished a rewrite with useReducer, following @kentcdobs article (ref below) which really gave me a solid result that suffers not one bit from these closure problems.

see: https://kentcdodds.com/blog/how-to-use-react-context-effectively

I condensed his readable boilerplate to my preferred level of DRYness -- reading his sandbox implementation will show you how it actually works.

Enjoy, I know I am !!

import React from 'react'

// ref: https://kentcdodds.com/blog/how-to-use-react-context-effectively

const ApplicationDispatch = React.createContext()
const ApplicationContext = React.createContext()

function stateReducer(state, action) {
  if (state.hasOwnProperty(action.type)) {
    return { ...state, [action.type]: state[action.type] = action.newValue };
  }
  throw new Error(`Unhandled action type: ${action.type}`);
}

const initialState = {
  keyCode: '',
  testCode: '',
  testMode: false,
  phoneNumber: '',
  resultCode: null,
  mobileInfo: '',
  configName: '',
  appConfig: {},
};

function DispatchProvider({ children }) {
  const [state, dispatch] = React.useReducer(stateReducer, initialState);
  return (
    <ApplicationDispatch.Provider value={dispatch}>
      <ApplicationContext.Provider value={state}>
        {children}
      </ApplicationContext.Provider>
    </ApplicationDispatch.Provider>
  )
}

function useDispatchable(stateName) {
  const context = React.useContext(ApplicationContext);
  const dispatch = React.useContext(ApplicationDispatch);
  return [context[stateName], newValue => dispatch({ type: stateName, newValue })];
}

function useKeyCode() { return useDispatchable('keyCode'); }
function useTestCode() { return useDispatchable('testCode'); }
function useTestMode() { return useDispatchable('testMode'); }
function usePhoneNumber() { return useDispatchable('phoneNumber'); }
function useResultCode() { return useDispatchable('resultCode'); }
function useMobileInfo() { return useDispatchable('mobileInfo'); }
function useConfigName() { return useDispatchable('configName'); }
function useAppConfig() { return useDispatchable('appConfig'); }

export {
  DispatchProvider,
  useKeyCode,
  useTestCode,
  useTestMode,
  usePhoneNumber,
  useResultCode,
  useMobileInfo,
  useConfigName,
  useAppConfig,
}

with a usage similar to this:

import { useHistory } from "react-router-dom";

// https://react-bootstrap.github.io/components/alerts
import { Container, Row } from 'react-bootstrap';

import { useAppConfig, useKeyCode, usePhoneNumber } from '../../ApplicationDispatchProvider';

import { ControlSet } from '../../components/control-set';
import { keypadClass } from '../../utils/style-utils';
import { MaskedEntry } from '../../components/masked-entry';
import { Messaging } from '../../components/messaging';
import { SimpleKeypad, HandleKeyPress, ALT_ID } from '../../components/simple-keypad';

export const AltIdPage = () => {
  const history = useHistory();
  const [keyCode, setKeyCode] = useKeyCode();
  const [phoneNumber, setPhoneNumber] = usePhoneNumber();
  const [appConfig, setAppConfig] = useAppConfig();

  const keyPressed = btn => {
    const maxLen = appConfig.phoneNumberEntry.entryLen;
    const newValue = HandleKeyPress(btn, phoneNumber).slice(0, maxLen);
    setPhoneNumber(newValue);
  }

  const doSubmit = () => {
    history.push('s');
  }

  const disableBtns = phoneNumber.length < appConfig.phoneNumberEntry.entryLen;

  return (
    <Container fluid className="text-center">
      <Row>
        <Messaging {...{ msgColors: appConfig.pageColors, msgLines: appConfig.entryMsgs.altIdMsgs }} />
      </Row>
      <Row>
        <MaskedEntry {...{ ...appConfig.phoneNumberEntry, entryColors: appConfig.pageColors, entryLine: phoneNumber }} />
      </Row>
      <Row>
        <SimpleKeypad {...{ keyboardName: ALT_ID, themeName: appConfig.keyTheme, keyPressed, styleClass: keypadClass }} />
      </Row>
      <Row>
        <ControlSet {...{ btnColors: appConfig.buttonColors, disabled: disableBtns, btns: [{ text: 'Submit', click: doSubmit }] }} />
      </Row>
    </Container>
  );
};

AltIdPage.propTypes = {};

Now everything persists smoothly everywhere across all my pages

Nice!

Thanks Kent!

WARNING in budgets, maximum exceeded for initial

Open angular.json file and find budgets keyword.

It should look like:

    "budgets": [
       {
          "type": "initial",
          "maximumWarning": "2mb",
          "maximumError": "5mb"
       }
    ]

As you’ve probably guessed you can increase the maximumWarning value to prevent this warning, i.e.:

    "budgets": [
       {
          "type": "initial",
          "maximumWarning": "4mb", <===
          "maximumError": "5mb"
       }
    ]

What does budgets mean?

A performance budget is a group of limits to certain values that affect site performance, that may not be exceeded in the design and development of any web project.

In our case budget is the limit for bundle sizes.

See also:

Git fatal: protocol 'https' is not supported

I encountered the same problem after freshly installing git on Windows 10 and running it for the first time. Restarting the bash window solved the problem.

Can't perform a React state update on an unmounted component

The solution from @ford04 didn't worked to me and specially if you need to use the isMounted in multiple places (multiple useEffect for instance), it's recommended to useRef, as bellow:

  1. Essential packages
"dependencies": 
{
  "react": "17.0.1",
}
"devDependencies": { 
  "typescript": "4.1.5",
}

  1. My Hook Component
export const SubscriptionsView: React.FC = () => {
  const [data, setData] = useState<Subscription[]>();
  const isMounted = React.useRef(true);

  React.useEffect(() => {
    if (isMounted.current) {
      // fetch data
      // setData (fetch result)

      return () => {
        isMounted.current = false;
      };
    }
  }
});

UnhandledPromiseRejectionWarning: This error originated either by throwing inside of an async function without a catch block

I suggest removing the below code from getMails

 .catch(error => { throw error})

In your main function you should put await and related code in Try block and also add one catch block where you failure code.


you function gmaiLHelper.getEmails should return a promise which has reject and resolve in it.

Now while calling and using await put that in try catch block(remove the .catch) as below.

router.get("/emailfetch", authCheck, async (req, res) => {
  //listing messages in users mailbox 
try{
  let emailFetch = await gmaiLHelper.getEmails(req.user._doc.profile_id , '/messages', req.user.accessToken)
}
catch (error) { 
 // your catch block code goes here
})

How to make an AlertDialog in Flutter?

Another easy option to show Dialog is to use stacked_services package

 _dialogService.showDialog(
      title: "Title",
      description: "Dialog message Tex",
         );
     });

dyld: Library not loaded: /usr/local/opt/icu4c/lib/libicui18n.62.dylib error running php after installing node with brew on Mac

Seems like it is impossible to link icu4c using brew after latest OS X update. Which makes things more interesting. The only solution I found working for me:

  1. Download and compile icu4c 62.1 to /usr/local/icu4c/62.1
mkdir ~/sources
cd ~/sources
wget http://download.icu-project.org/files/icu4c/62.1/icu4c-62_1-src.tgz
tar xvzf icu4c-62_1-src.tgz
cd icu/source/

sudo mkdir /usr/local/icu4c/62.1
./configure --prefix=/usr/local/icu4c/62.1
make
sudo make install
  1. Link libs:
ln -s /usr/local/icu4c/62.1/lib/*.dylib /usr/local/include/
  1. Set DYLD_LIBRARY_PATH in ~/.bash_profile:
export DYLD_LIBRARY_PATH=/usr/local/include

React hooks useState Array

The accepted answer shows the correct way to setState but it does not lead to a well functioning select box.

import React, { useState } from "react"; 
import ReactDOM from "react-dom";

const initialValue = { id: 0,value: " --- Select a State ---" };

const options = [
    { id: 1, value: "Alabama" },
    { id: 2, value: "Georgia" },
    { id: 3, value: "Tennessee" }
];

const StateSelector = () => {   
   const [ selected, setSelected ] = useState(initialValue);  

     return (
       <div>
          <label>Select a State:</label>
          <select value={selected}>
            {selected === initialValue && 
                <option disabled value={initialValue}>{initialValue.value}</option>}
            {options.map((localState, index) => (
               <option key={localState.id} value={localState}>
                   {localState.value}
               </option>
             ))}
          </select>
        </div>
      ); 
};

const rootElement = document.getElementById("root");
ReactDOM.render(<StateSelector />, rootElement);

HTTP Error 500.30 - ANCM In-Process Start Failure

From ASP.NET Core 3.0+ and visual studio 19 version 16.3+ You will find section in project .csproj file are like below-

  <PropertyGroup>
    <TargetFramework>netcoreapp3.1</TargetFramework>
  </PropertyGroup>

There is no AspNetCoreHostingModel property there. You will find Hosting model selection in the properties of the project. Right-click the project name in the solution explorer. Click properties.

enter image description here

Click the Debug menu.

enter image description here

enter image description here

Scroll down to find the Hosting Model option.

enter image description here

Select Out of Process.

enter image description here

Save the project and run IIS Express.

UPDATE For Server Deployment:

When you publish your application in the server there is a web config file like below:

enter image description here

change value of 'hostingModel' from 'inprocess' to 'outofprocess' like below:

enter image description here

"Repository does not have a release file" error

I have been having this issue for a couple of weeks and finally decided to sit down and try and fix it. I have no interest in config file editing as I'm primarily a Windows user.

In a fit of "clickyness" I noticed that the ubuntu server location was set "for United kingdom". I switched this over to "Main Server" and hey presto... it all stared updating.

So, it seems like the regionalised server (for the UK at least) has a very limited support window so if you are an infrequent user it is likely it will not have a valid upgrade path from your current version to the latest.

Edit: I only just noticted the previous reply, after posting. 100% agree.

Can I set state inside a useEffect hook

useEffect can hook on a certain prop or state. so, the thing you need to do to avoid infinite loop hook is binding some variable or state to effect

For Example:

useEffect(myeffectCallback, [])

above effect will fire only once the component has rendered. this is similar to componentDidMount lifecycle

const [something, setSomething] = withState(0)
const [myState, setMyState] = withState(0)
useEffect(() => {
  setSomething(0)
}, myState)

above effect will fire only my state has changed this is similar to componentDidUpdate except not every changing state will fire it.

You can read more detail though this link

Android Gradle 5.0 Update:Cause: org.jetbrains.plugins.gradle.tooling.util

I solved this issue after changing the "Gradle Version" and "Android Plugin version".

You just goto "File>>Project Structure>>Project>>" and make changes here. I have worked a combination of versions from another working project of mine and added to the Project where I was getting this problem.

TypeScript and React - children type?

The general way to find any type is by example. The beauty of typescript is that you have access to all types, so long as you have the correct @types/ files.

To answer this myself I just thought of a component react uses that has the children prop. The first thing that came to mind? How about a <div />?

All you need to do is open vscode and create a new .tsx file in a react project with @types/react.

import React from 'react';

export default () => (
  <div children={'test'} />
);

Hovering over the children prop shows you the type. And what do you know -- Its type is ReactNode (no need for ReactNode[]).

enter image description here

Then if you click into the type definition it brings you straight to the definition of children coming from DOMAttributes interface.

// node_modules/@types/react/index.d.ts
interface DOMAttributes<T> {
  children?: ReactNode;
  ...
}

Note: This process should be used to find any unknown type! All of them are there just waiting for you to find them :)