As when changing the brightness with setBrightness, it is additionally stored in the shared preferences.

So I think it's necessary to do the same for setThemeData

In main.dart I have this:

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return new DynamicTheme(
      defaultBrightness: Brightness.light,
      data: (brightness) => new ThemeData(
        primarySwatch: Colors.pink,
        primaryColorBrightness: Brightness.dark,
        accentColor: Colors.lightBlue
      ),
      themedWidgetBuilder: (context, theme) {
        return new MaterialApp(
          title: 'Top Tens',
          theme: theme,
          home: new LandingPage(title: 'TOP TENS'),
        );
      }
    );


    
  }
}

and on a screen later on in the app I call this method:

 _setTheme() {
    DynamicTheme.of(context).setBrightness(Brightness.dark);
}

but nothing happens, and there is no error thrown. Any ideas what I may have done wrong?

Change this at dynamic_theme.dart:

static DynamicThemeState of(BuildContext context) {
    return context.ancestorStateOfType(const TypeMatcher<DynamicThemeState>());
}

To this:

static DynamicThemeState of(BuildContext context) {
    return context.findAncestorStateOfType<State<DynamicTheme>>();
}

The shared-preferences plugin is currently only available for mobile. You could make this library usable for Desktop if you ask if the plugin is accessable before asking for shared preferences.

[ERROR:c:\b\s\w\ir\cache\builder\src\flutter\lib\ui\ui_dart_state.cc(157)] Unhandled Exception: MissingPluginException(No implementation found for method getAll on channel plugins.flutter.io/shared_preferences)
#0      DynamicThemeState.loadBrightness (package:dynamic_theme/dynamic_theme.dart:84:37)
<asynchronous suspension>
#1      DynamicThemeState.initState (package:dynamic_theme/dynamic_theme.dart:46:5)
#2      StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:4640:58)
#3      ComponentElement.mount (package:flutter/src/widgets/framework.dart:4476:5)
#4      Element.inflateWidget (package:flutter/src/widgets/framework.dart:3446:14)
#5      Element.updateChild (package:flutter/src/widgets/framework.dart:3214:18)
#6      RenderObjectToWidgetElement._rebuild (package:flutter/src/widgets/binding.dart:1142:16)
#7      RenderObjectToWidgetElement.mount (package:flutter/src/widgets/binding.dart:1113:5)
#8      RenderObjectToWidgetAdapter.attachToRenderTree.<anonymous closure> (package:flutter/src/widgets/binding.dart:1055:17)
#9      BuildOwner.buildScope (package:flutter/src/widgets/framework.dart:2607:19)
#10     RenderObjectToWidgetAdapter.attachToRenderTree (package:flutter/src/widgets/binding.dart:1054:13)
#11     WidgetsBinding.attachRootWidget (package:flutter/src/widgets/binding.dart:935:7)
#12     WidgetsBinding.scheduleAttachRootWidget.<anonymous closure> (package:flutter/src/widgets/binding.dart:917:7)
#13     _rootRun (dart:async/zone.dart:1129:38)
#14     _CustomZone.run (dart:async/zone.dart:1026:19)
#15     _CustomZone.runGuarded (dart:async/zone.dart:928:7)
#16     _CustomZone.bindCallbackGuarded.<anonymous closure> (dart:async/zone.dart:968:23)
#17     _rootRun (dart:async/zone.dart:1133:13)
#18     _CustomZone.run (dart:async/zone.dart:1026:19)
#19     _CustomZone.bindCallback.<anonymous closure> (dart:async/zone.dart:952:23)
#20     Timer._createTimer.<anonymous closure> (dart:async-patch/timer_patch.dart:23:15)
#21     _Timer._runTimers (dart:isolate-patch/timer_impl.dart:398:19)
#22     _Timer._handleMessage (dart:isolate-patch/timer_impl.dart:429:5)
#23     _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:168:12)

Hi, First of all thanks so much for a great library. This saves my time quite a lot. please upgrade this library to a newest flutter version, including its dependency especially share_preference.

Thank you

After upgrading to the dev channel -- I can't use dynamic_theme due to a SDK compatibility error..??

Running "flutter packages get" in flutter_login... The current Dart SDK version is 2.1.0-dev.1.0.flutter-ccb16f7282.

Because flutter_login depends on dynamic_theme from git which requires SDK version <2.0.0, version solving failed. pub get failed (1)

-- Can this be resolved?

Cheers!

My MyApp class

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return new DynamicTheme(
      defaultBrightness: Brightness.light,
      data: (brightness) => new ThemeData(
        brightness: brightness,
      ),
      themedWidgetBuilder: (context, theme) {
        return new MaterialApp(
          title: 'Omnibus',
          theme: theme,
          home: new SplashScreen(
            title: 'Omnibus',
          ),
        );
      },
    );
  }
}

How I'm changing the theme:

new IconButton(
  icon: new Icon(Icons.palette),
  color: Color.fromARGB(255, 15, 84, 108),
  onPressed: (){
    DynamicTheme.of(context).setBrightness(Brightness.dark);    
    DynamicTheme.of(context).setThemeData(new ThemeData(
      primaryColor: Color.fromARGB(255, 15, 84, 108),
      accentColor: Colors.yellow,
    ));
  }
),

The brightness is being changed properly, however the primary color or the accent color are not.

Can someone please indicate what the latest version number of this library is, the one which supports null-safety? There are a couple posts in the "Issues" which allude to what is supposed to work but nothing definitive (A sampling of a working example from pub spec.yaml is always useful).

Two weeks ago my project compiled fine. Now I have spent 3 hours trying to resolve issues with this library and the shared_preferences library.

I have an app that itself is fairly new and has been written to support null safety. And as noted a couple weeks ago all was good. No issues.

Today I needed to make a small code change and I am now battling version hell on these two libraries for some unknown reason.

It would be very helpful if someone would document this library's latest version # I can use in the pubspec.yaml file and the version of shared_preferences this library needs for support purposes.

Thank you.....

=====

Note when I place the following in my pubspec.yaml

dependency_overrides: dynamic_theme: shared_preferences: 2.0.13

I get the following when I do a "pub get"

Warning: You are using these overridden dependencies: ! dynamic_theme 1.0.1 ! shared_preferences 2.0.13

A compile cycle gives me:

Error: Cannot run with sound null safety, because the following dependencies don't support null safety:

• package:dynamic_theme

I'm trying to migrate my apps to nullsafety since Flutter 2.0 is in the stable channel now. This package depends on shared_preferences 0.5.x, which prevents me from upgrading to version 2.0.x. The new version has a breaking change; "Setters no longer accept null to mean removing values. If you were previously using set*(key, null) for removing, use remove(key) instead.". Since this package doesn't remove values by passing null to a setter, it should be safe to upgrade. https://pub.dev/packages/shared_preferences/changelog

It's probably a good idea to make this a major version upgrade, to maintain compatability with projects that doesn't use shared_preferences 2.0.x. This woluld also open the possibility of adding other null-safety related upgrades down the line.

I also took the libery of fixing some deprecation warnings.

When building the example project, you'll get this massive warning:

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Warning
──────────────────────────────────────────────────────────────────────────────
Your Flutter application is created using an older version of the Android
embedding. It's being deprecated in favor of Android embedding v2. Follow the
steps at

https://flutter.dev/go/android-project-migration

to migrate your project.
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

So I migrated the example project to Android embedding v2 by following the steps in the guide.

I am using this library with switch button. However, I always get this error.

The getter 'brightness' was called on null. Receiver: null Tried calling: brightness

How can I solve this? P.S I am new to flutter and I still don't know what this error means. Please help me. Thanks in advanced.

Fix #63

• Changed version number to 2.0.0
• Migration to null-safety (Fix #62, Fix #60, Fix #59)
• Now use the ThemeMode instead of Brightness (Fix #49).
• ThemedWidgetBuilder themedWidgetBuilder takes now the following parameters: BuildContext, ThemeMode, ThemeData.
• data parameter is now optional and has the type ThemeDataWithThemeModeBuilder.
• defaultBrightness became defaultThemeMode and use by default ThemeMode.system.
• loadBrightnessOnStart became loadThemeOnStart.
• import package:dynamic_theme/dynamic_theme.dart for both DynamicTheme and BrightnessSwitcherDialog.

Hi @Norbert515,

First of all, thank you for your package, it helped me a lot for the first few Flutter projects I've made.

Your package seems to be unmaintained for a bit of time so I took the liberty of adapting your original work to make it fit my needs with the most recent releases of Flutter in one of my recent project. I've changed a bit the base behavior you've created to support ThemeMode instead of Brightness changes so the theme data can be updated with the light, dark or system values.

If you are interested I'd be glad to merge my modifications in your package, but note there is a few breaking changes (this is why I'm talking about a v2.0). You can already check out the code from my repository: https://github.com/TesteurManiak/ygo_collection_manager/blob/main/dynamic_theme/lib/src/dynamic_theme.dart

And here's a sample of how I'm using it in my project:

class MyApp extends StatefulWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  State<StatefulWidget> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  @override
  Widget build(BuildContext context) {
    return DynamicTheme(
      themedWidgetBuilder: (_, themeMode) {
        return MaterialApp(
          themeMode: themeMode,
          darkTheme: MyThemes.dark,
          theme: MyThemes.light,
          initialRoute: LoadingView.routeName,
          onGenerateRoute: generateRoute,
        );
      },
    );
  }
}

As you can see with the most recent version of Flutter you don't need to change the value of theme depending of the application Brightness anymore, it is the themeMode parameter that will define which of theme or darkTheme should be used.

So if you are interested I'd be glad to merge my code in your repo so everyone can beneficiate from it (also I could be helping solving the remaining opened issues).

Here's the issues that would be solved with this new code:

• #62
• #60
• #59
• #49

you can run your project with --no-sound-null-safety so now you add this line your main.dart file in top(first line) with comment..

//@dart=2.9 (the 'd' here is lower case)