use the following command

    flutter --version

## Flutter

* **Version:**

    ```
    flutter --version
    ```

*  **SDK location:**

    ```
    where flutter
    ```

* **Detailed information:**

    ```
    flutter doctor -v
    ```

* **Upgrade**
  

    ```
    flutter upgrade
    ```

- **Change channel** to, say `beta`

    ```
    flutter channel beta
    flutter upgrade
    ```

---

## Dart

* **Version:**

    ```dart
    dart --version
    ```

* **SDK location:**

    ```
    where dart
    ```




As others have said use

    flutter doctor

or 

    flutter --version

If that is not working you need to make sure that the `flutter/bin` directory is in your path:

    echo $PATH

If it isn&#39;t see [this link][1] to add it.


  [1]: https://flutter.dev/docs/get-started/install/macos#update-your-path

## Flutter
Open the terminal, simply write

```
flutter --version
```
To see full overview and related other necessary things

```
flutter doctor
```
To see the installation path
```
echo $PATH
```
## Dart
To see the dart language version

```
dart --version
```

To get the current version of the Flutter SDK, including its framework, engine, and tools:

    flutter --version

Also you can find it by

    flutter doctor

To view all commands that flutter supports:

 

    flutter --help --verbose

Simply navigate to flutter sdk folder and open the file `version`

    flutter/version 



If you want to check your flutter version:

    flutter --version

If you want to upgrade the flutter version:

    flutter upgrade


How can the `useEffect` hook (or any other hook for that matter) be used to replicate `componentWillUnmount`?


In a traditional class component I would do something like this:

```jsx
class Effect extends React.PureComponent {
    componentDidMount() { console.log(&quot;MOUNT&quot;, this.props); }
    componentWillUnmount() { console.log(&quot;UNMOUNT&quot;, this.props); }
    render() { return null; }
}
```

With the `useEffect` hook:

```jsx
function Effect(props) {
  React.useEffect(() =&gt; {
    console.log(&quot;MOUNT&quot;, props);

    return () =&gt; console.log(&quot;UNMOUNT&quot;, props)
  }, []);

  return null;
}
```
(Full example: https://codesandbox.io/s/2oo7zqzx1n)

This does not work, since the &quot;cleanup&quot; function returned in `useEffect` captures the props as they were during mount and not state of the props during unmount.

How could I get the latest version of the props in `useEffect` clean up *without* running the function body (or cleanup) on every prop change?


A similar [question][1] does not address the part of having access to the latest props.

The [react docs][2] state:

&gt; If you want to run an effect and clean it up only once (on mount and unmount), you can pass an empty array ([]) as a second argument. This tells React that your effect doesn’t depend on any values from props or state, so it never needs to re-run.


In this case however I depend on the props... but only for the cleanup part...


  [1]: https://stackoverflow.com/questions/55020041/react-hooks-useeffect-cleanup-for-only-componentwillunmount
  [2]: https://reactjs.org/docs/hooks-effect.html

componentWillUnmount with React useEffect hook

I was experimenting with the new Hook feature in React. Considering I have the following two components (using React Hooks) - 

    const HookComponent = () =&gt; {
      const [username, setUsername] = useState(&#39;Abrar&#39;);
      const [count, setState] = useState();
      const handleChange = (e) =&gt; {
        setUsername(e.target.value);
      }
    
      return (
        &lt;div&gt;
          &lt;input name=&quot;userName&quot; value={username} onChange={handleChange}/&gt;
          &lt;p&gt;{username}&lt;/p&gt;
          &lt;p&gt;From HookComponent: {count}&lt;/p&gt;
        &lt;/div&gt;
      )
    }
    
    
    const HookComponent2 = () =&gt; {
      const [count, setCount] = useState(999);
      return (
        &lt;div&gt;
          &lt;p&gt;You clicked {count} times&lt;/p&gt;
          &lt;button onClick={() =&gt; setCount(count + 1)}&gt;
            Click me
          &lt;/button&gt;
        &lt;/div&gt;
      );
    }

Hooks claim to solve the problem of sharing stateful logic between components but I found that the states between `HookComponent` and `HookComponent2` are not sharable. For example the change of `count` in `HookComponent2` does not render a change in the `HookComponent`. 

Is it possible to share states between components using the `useState()` hook?

Is it possible to share states between components using the useState() hook in React?

How do I find the version of Flutter I have installed on my computer?

How to check the installed version of Flutter?

<p>How do I find the version of Flutter I have installed on my computer?</p>


I wrote an iteration on list of letters and put inside cards on screen using &quot;map&quot; class.

In the code you can see that I made a row, and using &quot;map&quot; printed all the userBoard on cards to the screen. I want to add some logic inside so I need to get the id of the element (for taping event).
Is there a way that I can do that?

Actually, I want to get a specific index of element over userBoard.

Code: 

```
Widget build(BuildContext context) {
    return Row(
      mainAxisAlignment: MainAxisAlignment.spaceEvenly,
      children: &lt;Widget&gt;[
            Row(
              children: userBoard
                  .map((element) =&gt; Stack(children: &lt;Widget&gt;[
                        Align(
                          alignment: Alignment(0, -0.6),
                          child: GestureDetector(
                            onTap: (() {
                              setState(() {
                                // print(&quot;element=${element.toString()}&quot;);
                                // print(&quot;element=${userBoard[element]}&quot;);
                              });
                            }),
                            child: SizedBox(
                              width: 40,
                              height: 60,
                              child: Card(
                                  shape: RoundedRectangleBorder(
                                    borderRadius: BorderRadius.circular(5.0),
                                  ),
                                  child: Center(
                                    child: Text(element,
                                        style: TextStyle(fontSize: 30)),
                                  )),
                            ),
                          ),
                        )
                      ]))
                  .toList(),
            )
          ],
        ),
}
```

[**Picture** - each card is &quot;element&quot; of the map. I want to get the indexes for the function onTap.][1]




  [1]: https://i.stack.imgur.com/2rzap.png

Get iteration index from List.map()

I&#39;m able to do something like the following in TypeScript

```
class Foo {
  private constructor () {}
}
```

so this `constructor` is accessible only from inside the class itself.

How to achieve the same functionality in Dart?

Is it possible to have a private constructor in dart?

I want to understand the difference between `extends`, `implements` and `with`. When do I use each keyword?

&quot;extends&quot; versus &quot;implements&quot; versus &quot;with&quot;

I have to create a Card like this:

[![enter image description here][1]][1]

I had written below code to achieve the desired UI, but it didn&#39;t work as expected.

```dart
Card(
  elevation: 5,
  shape: RoundedRectangleBorder(
    borderRadius: BorderRadius.only(
      bottomRight: Radius.circular(10),
      topRight: Radius.circular(10)),
    side: BorderSide(width: 5, color: Colors.green)),
  child: ListTile(),
)
```

The code above produced this:

[![enter image description here][2]][2]

Whereas using the code below: 

```dart
Card(
  elevation: 5,
  shape: Border(right: BorderSide(color: Colors.red, width: 5)),
  child: ListTile(),
)
```

generated this output:

[![enter image description here][3]][3]

How can I create the required UI in flutter?


  [1]: https://i.stack.imgur.com/NBfnJ.png
  [2]: https://i.stack.imgur.com/Gub8q.png
  [3]: https://i.stack.imgur.com/hBp1D.png

Rounded corner Card Widget with right border in flutter

I am making an application using flutter framework .
During this I came across with the keywords in Dart `async` and `async*`.
Can anybody tell me what&#39;s the difference between them?

What&#39;s the difference between async and async* in Dart?

I just wanted to test something out real quick. So I ran a docker container and I wanted to check which version I was running:

    $ docker run -it ubuntu    
    root@471bdb08b11a:/# lsb_release -a
    bash: lsb_release: command not found
    root@471bdb08b11a:/# 

So I tried installing it (as [suggested here][1]):

    root@471bdb08b11a:/# apt install lsb_release
    Reading package lists... Done
    Building dependency tree       
    Reading state information... Done
    E: Unable to locate package lsb_release
    root@471bdb08b11a:/# 

Anybody any idea why this isn&#39;t working?

  [1]: http://www.andryhacks.com/bash-lsb_release-command-not-found/

lsb_release: command not found in latest Ubuntu Docker container

I created a conda environment with Python version 3.8, but it doesn&#39;t support matplotlib... So I am looking for something like this to change the Python version: `conda env my_env update to python=3.6`. Is this possible or do I need to recreate the environment?

I have miniconda installed.

How to change Python version of existing conda virtual environment?

After uploading a Flutter app to App Store Connect, I got the following email warning:

&gt; Dear Developer,
&gt; 
&gt; We identified one or more issues with a recent delivery for your app,
&gt; &quot;[APP NAME]&quot;. Your delivery was successful, but you may wish to correct
&gt; the following issues in your next delivery:
&gt; 
&gt; **Missing Push Notification Entitlement** - Your app appears to register with the Apple Push Notification service, but the app
&gt; signature&#39;s entitlements do not include the &quot;aps-environment&quot;
&gt; entitlement. If your app uses the Apple Push Notification service,
&gt; make sure your App ID is enabled for Push Notification in the
&gt; Provisioning Portal, and resubmit after signing your app with a
&gt; Distribution provisioning profile that includes the &quot;aps-environment&quot;
&gt; entitlement. Xcode does not automatically copy the aps-environment
&gt; entitlement from provisioning profiles at build time. This behavior is
&gt; intentional. To use this entitlement, either enable Push Notifications
&gt; in the project editor&#39;s Capabilities pane, or manually add the
&gt; entitlement to your entitlements file. For more information, see
&gt; https://developer.apple.com/library/content/documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/HandlingRemoteNotifications.html#//apple_ref/doc/uid/TP40008194-CH6-SW1.
&gt; 
&gt; After you’ve corrected the issues, you can use Xcode or Application
&gt; Loader to upload a new binary to App Store Connect.
&gt; 
&gt; Best regards,
&gt; 
&gt; The App Store Team

I don&#39;t use push notifications in my app? Why am I getting this warning? And how do I remove the &quot;aps-environment&quot; entitlement, wherever and whatever that is?

**Note:** This App Store issue has appeared multiple times on SO, sometimes because people needed to add push notifications (see [this][1] and [this][2]) and sometimes because they didn&#39;t (see [this][3] and [this][4]). This appears to be Flutter related in my case, though, so I am adding a new question.


  [1]: https://stackoverflow.com/questions/14807129/missing-push-notification-entitlement
  [2]: https://stackoverflow.com/questions/27945557/missing-push-notification-entitlement-warning
  [3]: https://stackoverflow.com/questions/32261604/missing-push-notification-entitlement-ios-app-submission-i-dont-use-it
  [4]: https://stackoverflow.com/questions/32127500/how-to-remove-push-notification-api/32128846#32128846

Flutter iOS app submission issue warning: Missing Push Notification Entitlement

I need to know whether Flutter will render the iOS Cupertino style on iOS and Material on Android with a single codebase. I want to know this before starting to develop my app with Flutter. 

If it&#39;s not, how would I manage the two different UI in a single code? I can&#39;t possibly use if/else everywhere over the code.

Does Flutter automatically display Cupertino UI in iOS and Material in Android with a single codebase?

      Widget build(context) {
        return Row(
          mainAxisSize: MainAxisSize.min,
          children: [
            Container(
              width: 300,
              padding: EdgeInsets.all(10),
              decoration: BoxDecoration(
                color: color ?? Colors.blue,
                borderRadius: BorderRadius.circular(10)
              ),
              child: msg
            )
          ],  
        );
      }

This is build method of my widget and It renders this UI depending on what I pass as `msg` paramter

1. Loading text
[![enter image description here][1]][1]
2. Some very long text
[![enter image description here][2]][2]

Now the issue I am facing is that I am not able to wrap the text inside this container/blue box without setting it&#39;s width but If I set width of container/blue box then it will always stay that wide no matter how short the text is.

Now is there a way to set maxWidth (like let&#39;s say 500) of container/blue box? So that the blue box will become as wide as required for small text like &quot;Loading&quot; and for long text it will expand till it reaches width of 500 units and then will wrap the text ?

**Required output for long text:**

For small text like loading I dont want any change in UI but for long text I want it to look like this.
[![enter image description here][3]][3]

  [1]: https://i.stack.imgur.com/JggN2.png
  [2]: https://i.stack.imgur.com/Pu2Yp.png
  [3]: https://i.stack.imgur.com/yH6hw.png

Limit max width of Container in Flutter

I had developing app using Android, now I use Flutter, but I want to find the property of Text that is same to `android:includeFontPadding` and `android:lineSpacingExtra`?

Content Type	Original Author	Original Content on Stackoverflow
Question	user8637708	View Question on Stackoverflow
Solution 1 - Dart	Sami Kanafani	View Answer on Stackoverflow
Solution 2 - Dart	CopsOnRoad	View Answer on Stackoverflow
Solution 3 - Dart	Suragch	View Answer on Stackoverflow
Solution 4 - Dart	Mijanur Rahman	View Answer on Stackoverflow
Solution 5 - Dart	Paresh Mangukiya	View Answer on Stackoverflow
Solution 6 - Dart	Osama Remlawi	View Answer on Stackoverflow
Solution 7 - Dart	Tai-sung Wang	View Answer on Stackoverflow

How to check the installed version of Flutter?

Dart Problem Overview

Dart Solutions

Solution 1 - Dart

Solution 2 - Dart

Flutter

Dart

Solution 3 - Dart

Solution 4 - Dart

Flutter

Dart

Solution 5 - Dart

Solution 6 - Dart

Solution 7 - Dart

Is it possible to share states between components using the useState() hook in React?

componentWillUnmount with React useEffect hook

Attributions