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<topic_end>
<topic_start>
Where do I store my image files?
Xamarin.Forms has no platform independent way of storing images,
you had to place images in the iOS xcasset folder,
or on Android in the various drawable folders.While Android and iOS treat resources and assets as distinct items,
Flutter apps have only assets.
All resources that would live in the
Resources/drawable-* folders on Android,
are placed in an assets’ folder for Flutter.Flutter follows a simple density-based format like iOS.
Assets might be 1.0x, 2.0x, 3.0x, or any other multiplier.
Flutter doesn’t have dps but there are logical pixels,
which are basically the same as device-independent pixels.
Flutter’s devicePixelRatio expresses the ratio
of physical pixels in a single logical pixel.The equivalent to Android’s density buckets are:Assets are located in any arbitrary folder—
Flutter has no predefined folder structure.
You declare the assets (with location)
in the pubspec.yaml file, and Flutter picks them up.To add a new image asset called my_icon.png to our Flutter project,
for example, and deciding that it should live in a folder we
arbitrarily called images, you would put the base image (1.0x)
in the images folder, and all the other variants in sub-folders
called with the appropriate ratio multiplier:Next, you’ll need to declare these images in your pubspec.yaml file:You can directly access your images in an Image.asset widget:
<code_start>@override
Widget build(BuildContext context) {
return Image.asset('images/my_icon.png');
}<code_end>
or using AssetImage:
<code_start>@override
Widget build(BuildContext context) {
return const Image(
image: AssetImage('images/my_image.png'),
);
}<code_end>
More detailed information can be found in Adding assets and images.<topic_end>
<topic_start>
Where do I store strings? How do I handle localization?
Unlike .NET which has resx files,
Flutter doesn’t currently have a dedicated system for handling strings.
At the moment, the best practice is to declare your copy text
in a class as static fields and access them from there. For example:
<code_start>class Strings {
static const String welcomeMessage = 'Welcome To Flutter';
}<code_end>
You can access your strings as such:
<code_start>Text(Strings.welcomeMessage);<code_end>
By default, Flutter only supports US English for its strings.
If you need to add support for other languages,
include the flutter_localizations package.
You might also need to add Dart’s intl
package to use i10n machinery, such as date/time formatting.To use the flutter_localizations package,
specify the localizationsDelegates and
supportedLocales on the app widget:
<code_start>import 'package:flutter_localizations/flutter_localizations.dart';
class MyWidget extends StatelessWidget {
const MyWidget({super.key});
@override
Widget build(BuildContext context) {
return const MaterialApp(
localizationsDelegates: <LocalizationsDelegate<dynamic>>[
// Add app-specific localization delegate[s] here
GlobalMaterialLocalizations.delegate,
GlobalWidgetsLocalizations.delegate,
],
supportedLocales: <Locale>[
Locale('en', 'US'), // English
Locale('he', 'IL'), // Hebrew
// ... other locales the app supports
],
);
}
}<code_end>
The delegates contain the actual localized values,
while the supportedLocales defines which locales the app supports.
The above example uses a MaterialApp,
so it has both a GlobalWidgetsLocalizations
for the base widgets localized values,
and a MaterialWidgetsLocalizations for the Material widgets localizations.
If you use WidgetsApp for your app, you don’t need the latter.
Note that these two delegates contain “default” values,
but you’ll need to provide one or more delegates
for your own app’s localizable copy,
if you want those to be localized too.When initialized, the WidgetsApp (or MaterialApp)
creates a Localizations widget for you,
with the delegates you specify.
The current locale for the device is always accessible
from the Localizations widget from the current context
(in the form of a Locale object), or using the Window.locale.To access localized resources, use the Localizations.of() method
to access a specific localizations class that is provided by a given delegate.
Use the intl_translation package to extract translatable copy
to arb files for translating, and importing them back into the app
for using them with intl.For further details on internationalization and localization in Flutter,
see the internationalization guide, which has sample code
with and without the intl package.<topic_end>
<topic_start>
Where is my project file?
In Xamarin.Forms you will have a csproj file.
The closest equivalent in Flutter is pubspec.yaml,
which contains package dependencies and various project details.
Similar to .NET Standard,
files within the same directory are considered part of the project.<topic_end>