A mix of digital topics.
To expand the height of TextField to match the parents widgets height, the following code can be used:
Container(
height: 500.0,
child: TextField(
expands: true,
minLines: null,
maxLines: null,
...
),
),
The important thing is, that both minLines and maxLines need to be set to null.
To set the height of the Container to match it’s parent or even the complete screen, height can be set to double.infinity.
In my case, a simple app should automatically use the theme (light or dark) of the system to style the user interface. By default, this should work when using ThemeMode.system (see flutter documentation). But it didn’t.
The themes have been defined as follows:
return MaterialApp(
themeMode: ThemeMode.system,
theme: ThemeData( ... ),
darkTheme: ThemeData( ...),
...
);
In addition, the WidgetsBindingObserver callback didChangePlatformBrightness() was never called. It was defined as follows:
class MyHomePageState extends State<MyHomePage> with WidgetsBindingObserver
{
@override
void initState() {
super.initState();
WidgetsBinding.instance.addObserver(this);
}
@override
void dispose() {
WidgetsBinding.instance.removeObserver(this);
super.dispose();
}
@override
void didChangePlatformBrightness() {
print(WidgetsBinding.instance.window.platformBrightness);
// > should print Brightness.light / Brightness.dark when you switch
super.didChangePlatformBrightness();
}
}
After hours and days of searching, it turned out, that the following definition was set in info.plist of iOS:
<key>UIUserInterfaceStyle</key>
<string>Light</string>
Removing this line solved the issue. This setting sets the apps theme to Light, which results in a constant value even if the user changed the brightness to dark. Without this line, UIUserInterfaceStyle depends on the global setting.
After switching the flutter channel to beta and back to stable, my app did not compile anymore. The compilation stopped with the error:
fatal error: 'Flutter/Flutter.h' file not found
Multiple flutter clean and channel switches did not work in this case.
The following commands fixed this behavior:
rm ios/Flutter/Flutter.podspec
flutter clean
See: https://github.com/flutter/flutter/issues/70895#issuecomment-744734693
The full documentation for this is available on flutter.dev
When creating json_serializable classes the first time, you’ll get errors similar to what is shown in the image below.
These errors are entirely normal and are simply because the generated code for the model class does not exist yet. To resolve this, run the code generator that generates the serialization boilerplate.
There are two ways of running the code generator.
By running
flutter pub run build_runner build
in the project root, you generate JSON serialization code for your models whenever they are needed. This triggers a one-time build that goes through the source files, picks the relevant ones, and generates the necessary serialization code for them.
While this is convenient, it would be nice if you did not have to run the build manually every time you make changes in your model classes.
A watcher makes our source code generation process more convenient. It watches changes in our project files and automatically builds the necessary files when needed. Start the watcher by running
flutter pub run build_runner watch
in the project root.
It is safe to start the watcher once and leave it running in the background.
Source: https://flutter.dev/docs/development/data-and-backend/json#code-generation