How do i use asset image in flutter for setting wallpaper in android

Question

I am unable to find the solution of setting asset image as wallpaper in android, while i am doing everything right as documented in official flutter document ion, in below image Set As Wallpaper button uses Method channel and use native code in java activity but could not set this image as wallpaper from java activity. Please guide. This image loaded from local assets folder in flutter

Answer 1

You can use package https://pub.dev/packages/wallpaper_manager
You can set wallpaper in Home screen or Lock screen
wall paper can from a File or Asset

code snippet

Future<void> setWallpaperFromAsset() async {
    setState(() {
      _wallpaperAsset = "Loading";
    });
    String result;
    String assetPath = "assets/tmp1.jpg";
    // Platform messages may fail, so we use a try/catch PlatformException.
    try {
      result = await WallpaperManager.setWallpaperFromAsset(
          assetPath, WallpaperManager.HOME_SCREEN);
    } on PlatformException {
      result = 'Failed to get wallpaper.';
    }

    // If the widget was removed from the tree while the asynchronous platform
    // message was in flight, we want to discard the reply rather than calling
    // setState to update our non-existent appearance.
    if (!mounted) return;

    setState(() {
      _wallpaperAsset = result;
    });
  }

working demo

full code

import 'package:flutter/material.dart';
import 'dart:async';

import 'package:flutter/services.dart';
import 'package:flutter_cache_manager/flutter_cache_manager.dart';
import 'package:wallpaper_manager/wallpaper_manager.dart';

void main() => runApp(MyApp());

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  String _platformVersion = 'Unknown';
  String _wallpaperFile = 'Unknown';
  String _wallpaperAsset = 'Unknown';

  @override
  void initState() {
    super.initState();
  }

  // Platform messages are asynchronous, so we initialize in an async method.
  Future<void> initPlatformState() async {
    String platformVersion;
    // Platform messages may fail, so we use a try/catch PlatformException.
    try {
      platformVersion = await WallpaperManager.platformVersion;
    } on PlatformException {
      platformVersion = 'Failed to get platform version.';
    }

    // If the widget was removed from the tree while the asynchronous platform
    // message was in flight, we want to discard the reply rather than calling
    // setState to update our non-existent appearance.
    if (!mounted) return;

    setState(() {
      _platformVersion = platformVersion;
    });
  }

  // Platform messages are asynchronous, so we initialize in an async method.
  Future<void> setWallpaperFromFile() async {
    setState(() {
      _wallpaperFile = "Loading";
    });
    String result;
    var file = await DefaultCacheManager().getSingleFile(
        'https://images.unsplash.com/photo-1542435503-956c469947f6');
    // Platform messages may fail, so we use a try/catch PlatformException.
    try {
      result = await WallpaperManager.setWallpaperFromFile(
          file.path, WallpaperManager.HOME_SCREEN);
    } on PlatformException {
      result = 'Failed to get wallpaper.';
    }

    // If the widget was removed from the tree while the asynchronous platform
    // message was in flight, we want to discard the reply rather than calling
    // setState to update our non-existent appearance.
    if (!mounted) return;

    setState(() {
      _wallpaperFile = result;
    });
  }

  // Platform messages are asynchronous, so we initialize in an async method.
  Future<void> setWallpaperFromAsset() async {
    setState(() {
      _wallpaperAsset = "Loading";
    });
    String result;
    String assetPath = "assets/tmp1.jpg";
    // Platform messages may fail, so we use a try/catch PlatformException.
    try {
      result = await WallpaperManager.setWallpaperFromAsset(
          assetPath, WallpaperManager.HOME_SCREEN);
    } on PlatformException {
      result = 'Failed to get wallpaper.';
    }

    // If the widget was removed from the tree while the asynchronous platform
    // message was in flight, we want to discard the reply rather than calling
    // setState to update our non-existent appearance.
    if (!mounted) return;

    setState(() {
      _wallpaperAsset = result;
    });
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
          appBar: AppBar(
            title: const Text('Plugin example app'),
          ),
          body: Column(
            children: <Widget>[
              RaisedButton(
                child: Text("Platform Version"),
                onPressed: initPlatformState,
              ),
              Center(
                child: Text('Running on: $_platformVersion\n'),
              ),
              RaisedButton(
                child: Text("Set wallpaper from file"),
                onPressed: setWallpaperFromFile,
              ),
              Center(
                child: Text('Wallpaper status: $_wallpaperFile\n'),
              ),
              RaisedButton(
                child: Text("Set wallpaper from asset"),
                onPressed: setWallpaperFromAsset,
              ),
              Center(
                child: Text('Wallpaper status: $_wallpaperAsset\n'),
              ),
            ],
          )),
    );
  }
}