android保存一张图片sendBroadcast代码_Android开发教程_开发教程

android保存图片后加了以下代码就可以了

sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE,Uri
                            .parse("file://" + _file)));

那么这个sendBroadcast到底是做什么的呢？广播，相当于iOS中NSNotificationCenter的postNotificationName。不过比iOS更加强大，iOS中只是app内适用，在android中发送一条广播其他app都可以收到，然后进行相应的处理。

发送广播比较

android

Intent it = new Intent("someNotification");
it.putExtra("some argv", "abcd");
sendBroadcast(it);

iOS

[[NSNotificationCenter defaultCenter] postNotificationName:AFNetworkingTaskDidCompleteNotification object:task userInfo:userInfo];

接收广播比较

android

private BroadcastReceiver br = new BroadcastReceiver() {

    @Override
    public void onReceive(Context context, Intent intent) {
      String someargv = intent.getStringExtra("some argv");
    }
  };
IntentFilter ifilter = new IntentFilter("someNotification");
registerReceiver(br, ifilter);

iOS

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(networkRequestDidFinish:) name:AFNetworkingTaskDidCompleteNotification object:nil];
- (void)networkRequestDidFinish:(NSNotification *)notification {
  NSDictionary * userDic = [notification userInfo];
    //some code
}

取消接收广播比较

android

registerReceiver(br, ifilter);

iOS

[[NSNotificationCenter defaultCenter] removeObserver:self];

总结

附app效果图

(责任编辑：好模板)