如何使用Flutter在iOS和Android上共享图像？

  • Z时代
  • 2024-01-10
  • 分类：问答

我想使用iOS和Android中的标准共享对话框共享图像。下面的代码主要来自https://pub.dartlang.org/packages/share（我仅以此为起点）（仅下面的Dart和Objective-C）。当前仅共享文本。

我不确定如何将图像转换为Dart中的字节流并在iOS和Android中进行处理，而不是我不确定的最佳方法。

镖

static const _kShareChannel = const MethodChannel('example.test.com/share');
Future<Null> shareImage(Image image) {
  assert(image != null);
  return _kShareChannel.invokeMethod('shareImage', image);
}

物镜

static NSString *const PLATFORM_CHANNEL = @"example.test.com/share";
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    [GeneratedPluginRegistrant registerWithRegistry:self];
    FlutterViewController* controller = (FlutterViewController*)self.window.rootViewController;
    FlutterMethodChannel *shareChannel = [FlutterMethodChannel methodChannelWithName:PLATFORM_CHANNEL
                            binaryMessenger:controller];
    [shareChannel setMethodCallHandler:^(FlutterMethodCall *call, FlutterResult result) {
        if ([@"shareImage" isEqualToString:call.method]) {
            [self share:call.arguments withController:[UIApplication sharedApplication].keyWindow.rootViewController];
            result(nil);
        } else {
            result([FlutterError errorWithCode:@"UNKNOWN_METHOD"
                                       message:@"Unknown share method called"
                                       details:nil]);
        }
    }];
    return [super application:application didFinishLaunchingWithOptions:launchOptions];
}
- (void)share:(id)sharedItems withController:(UIViewController *)controller {
    UIActivityViewController *activityViewController = [[UIActivityViewController alloc] initWithActivityItems:@[ sharedItems ]
                                  applicationActivities:nil];
    [controller presentViewController:activityViewController animated:YES completion:nil];
}

回答：

以下内容可让您UIActivityViewController在iOS上使用文件（在此示例中为图像）发送邮件，并在Android上作为共享意向文件。

FileProvider概述（Android）

更新pubspec.yaml以引用您的图像（如果是本地的话）（在此示例中为image.jpg），并使用该path_provider插件来访问文件系统。https://pub.dartlang.org/packages/path_provider

主镖

import 'dart:io';
import 'dart:typed_data';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:path_provider/path_provider.dart';
void main() => runApp(new MyApp());
class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      title: 'Share Demo',
      theme: new ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: new MyHomePage(title: 'Share Demo Home Page'),
    );
  }
}
class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);
  final String title;
  @override
  _MyHomePageState createState() => new _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(
        title: new Text(widget.title),
      ),
      body: new Center(
        child: new Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
          ],
        ),
      ),
      floatingActionButton: new FloatingActionButton(
        onPressed: _shareImage,
        tooltip: 'Share',
        child: new Icon(Icons.share),
      ),
    );
  }
  _shareImage() async {
    try {
      final ByteData bytes = await rootBundle.load('assets/image.jpg');
      final Uint8List list = bytes.buffer.asUint8List();
      final tempDir = await getTemporaryDirectory();
      final file = await new File('${tempDir.path}/image.jpg').create();
      file.writeAsBytesSync(list);
      final channel = const MethodChannel('channel:me.albie.share/share');
      channel.invokeMethod('shareFile', 'image.jpg');
    } catch (e) {
      print('Share error: $e');
    }
  }
}

AppDelegate.m

#include "AppDelegate.h"
#include "GeneratedPluginRegistrant.h"
@implementation AppDelegate
static NSString *const SHARE_CHANNEL = @"channel:me.albie.share/share";
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    [GeneratedPluginRegistrant registerWithRegistry:self];
    FlutterViewController* controller = (FlutterViewController*)self.window.rootViewController;
    FlutterMethodChannel *shareChannel =
    [FlutterMethodChannel methodChannelWithName:SHARE_CHANNEL
                                binaryMessenger:controller];
    [shareChannel setMethodCallHandler:^(FlutterMethodCall *call, FlutterResult result) {
        if ([@"shareFile" isEqualToString:call.method]) {
            [self shareFile:call.arguments
             withController:[UIApplication sharedApplication].keyWindow.rootViewController];
        }
    }];
    return [super application:application didFinishLaunchingWithOptions:launchOptions];
}
- (void)shareFile:(id)sharedItems withController:(UIViewController *)controller {
    NSMutableString *filePath = [NSMutableString stringWithString:sharedItems];
    NSString *docsPath = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) objectAtIndex:0];
    NSString *imagePath = [docsPath stringByAppendingPathComponent:filePath];
    NSURL *imageUrl = [NSURL fileURLWithPath:imagePath];
    NSData *imageData = [NSData dataWithContentsOfURL:imageUrl];
    UIImage *shareImage = [UIImage imageWithData:imageData];
    UIActivityViewController *activityViewController =
    [[UIActivityViewController alloc] initWithActivityItems:@[ shareImage ]
                                      applicationActivities:nil];
    [controller presentViewController:activityViewController animated:YES completion:nil];
}
@end

MainActivity.java

package com.example.share;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import java.io.File;
import io.flutter.app.FlutterActivity;
import io.flutter.plugin.common.MethodCall;
import io.flutter.plugin.common.MethodChannel;
import io.flutter.plugins.GeneratedPluginRegistrant;
import android.support.v4.content.FileProvider;
public class MainActivity extends FlutterActivity {
    private static final String SHARE_CHANNEL = "channel:me.albie.share/share";
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        GeneratedPluginRegistrant.registerWith(this);
        new MethodChannel(this.getFlutterView(), SHARE_CHANNEL).setMethodCallHandler(new MethodChannel.MethodCallHandler() {
            public final void onMethodCall(MethodCall methodCall, MethodChannel.Result result) {
                if (methodCall.method.equals("shareFile")) {
                    shareFile((String) methodCall.arguments);
                }
            }
        });
    }
    private void shareFile(String path) {
        File imageFile = new File(this.getApplicationContext().getCacheDir(), path);
        Uri contentUri = FileProvider.getUriForFile(this, "me.albie.share", imageFile);
        Intent shareIntent = new Intent(Intent.ACTION_SEND);
        shareIntent.setType("image/jpg");
        shareIntent.putExtra(Intent.EXTRA_STREAM, contentUri);
        this.startActivity(Intent.createChooser(shareIntent, "Share image using"));
    }
}

AndroidManifest.xml

<provider
    android:name="android.support.v4.content.FileProvider"
    android:authorities="me.albie.share"
    android:exported="false"
    android:grantUriPermissions="true">
    <meta-data
        android:name="android.support.FILE_PROVIDER_PATHS"
        android:resource="@xml/file_paths" />
</provider>

xml / file_paths.xml

<?xml version="1.0" encoding="utf-8"?>
<paths>
    <cache-path name="images" path="/"/>
</paths>

build.gradle（应用程序）

dependencies {
    ...
    implementation 'com.android.support:support-v4:27.1.1'
}

以上是 如何使用Flutter在iOS和Android上共享图像？ 的全部内容， 来源链接： utcz.com/qa/405346.html

回到顶部