从Android平台向Flutter发送位图

// 将位图转换为字节数组
Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.image);
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream);
byte[] byteArray = stream.toByteArray();

// 通过MethodChannel将字节数组传递给Flutter端
MethodChannel methodChannel = new MethodChannel(getFlutterView(), "image_channel");
methodChannel.invokeMethod("sendImage", byteArray);

// 注册MethodChannel，接收Android端传递的字节数组
MethodChannel methodChannel = MethodChannel('image_channel');
methodChannel.setMethodCallHandler((call) async {
  if (call.method == 'sendImage') {
    List<int> byteArray = call.arguments;
    // 将字节数组转换为Flutter的Image对象
    Image image = Image.memory(byteArray);
    // 使用Image对象进行显示或处理
  }
});

// 或者使用BasicMessageChannel
BasicMessageChannel('image_channel', StandardMessageCodec())
  .setMessageHandler((message) async {
    List<int> byteArray = message;
    // 将字节数组转换为Flutter的Image对象
    Image image = Image.memory(byteArray);
    // 使用Image对象进行显示或处理
  });