When I call setState in StatefulWidget, other widgets refresh too-CodePudding

The Goal

Use setState without redraw other widgets

What I Did

I'm using youtube_player_flutter to show YouTube video.

            String id;
            YoutubePlayerController _youtubeController =
                YoutubePlayerController(
              initialVideoId: id,
              flags: YoutubePlayerFlags(....);


            //Then call this:
                          YoutubePlayer(
                            controller: _youtubeController,
                            showVideoProgressIndicator: true,
                          ),

In same StatefulWidget I have a Text, Button and YoutubePlayer.

String str = "abc";

//in Column or Row
Text(str),
ElevatedButton(child: Text("Push"), onPressed: () { setState((){ str = "ABC" });}),
YoutubePlayer(
 controller: _youtubeController,
 showVideoProgressIndicator: true,
),

The Problem

When I call setState, YoutubePlayer is refreshed. This means Youtube video is loaded again, and progress is initialized.

I can't define YoutubePlayer as const because initialVideoId is indefinite.

flutter doctor

[√] Flutter (Channel beta, 2.6.0-5.2.pre, on Microsoft Windows [Version 10.0.22000.282], locale ja-JP)
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[√] Android toolchain - develop for Android devices (Android SDK version 29.0.3)
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    • Platform android-30, build-tools 29.0.3
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    • Java version OpenJDK Runtime Environment (build 11.0.8 10-b944.6842174)
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    • Java version OpenJDK Runtime Environment (build 11.0.8 10-b944.6842174)

[√] VS Code (version 1.61.2)
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[√] Connected device (3 available)
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• No issues found!

CodePudding user response：

setState refresh widget itself and it child widgets. So, if you put widget which you want to refresh on level beneath YouTube player, it won't refresh that player

CodePudding user response：

Well, setState does exactly that, it redraws all the page. If you want to redraw only one widget, you have to use streams/state management. This is why using setState is not a good practice, the cost/benefit is too high. Try to use MobX, GetX, RxDart, Cubit for state management.