back_button_interceptor

The BackButtonInterceptor may be used to intercept the Android back-button, as an alternative to WillPopScope.

You may set a function to be called when the back button is tapped. This function may perform some useful work, and then, if it returns false, the default button process (usually popping a Route) will not be fired.

Note: Only one function may be defined at a time, and setting a function will remove the previous one. After you've finished you MUST remove the function by setting it to null, or calling the remove() method.

Usage

Import the package

First, add back_button_interceptor as a dependency in your pubspec.yaml

Then, import it:

import 'package:back_button_interceptor/back_button_interceptor.dart';

Example usage

@override
void initState() {
    super.initState();
    BackButtonInterceptor.set(() {
       print("BACK BUTTON!");
       return false;
       });
}

 @override
 void dispose() {
    BackButtonInterceptor.remove();
    super.dispose();
 }

Don't forget to check the example tab.

See also:

Libraries

back_button_interceptor

Dart

dart:ui
Built-in types and core primitives for a Flutter application. [...]

Core

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