Question

从这些例子来看,这是直截了当的。也许你可以向我表明我错了。我可以不参加从当地机构广播的活动。

我的活动1

startService(new Intent(Activity1.this, Service1.class));

活动1随后开始活动2:

startActivity(new Intent(Activity1.this, Activity2.class));

服务1是一个地方机构,负责倾听下载:

protected final BroadcastReceiver service2DownloadBroadcastReceiver = new BroadcastReceiver()
{
    public void onReceive(final Context context, final Intent intent)
    {
        ...
        broadcastDownloadFinished(Uri.fromFile(downloadedFile));

广播接收器1 然后播放自己的信息:

protected Intent broadcastDownloadFinished(final Uri uri)
{
    final Intent intent = new Intent(ACTION_DOWNLOAD_FINISHED).setData(checkNotNull(uri));
    sendBroadcast(intent);

活动2当时处于地下,聆听了行动...... DOWNLOAD -FINISHED 意向,利用自己的广播接收器:

private final BroadcastReceiver activity2DownloadBroadcastReceiver = new BroadcastReceiver()
{
    public void onReceive(final Context context, final Intent intent)
    {
        Log.i(Activity2.class.getSimpleName(), "Received download event: " + intent.getAction() + " " + intent.getData());

活动2当然登记接收人:

protected void onResume()
{
    super.onResume();
    final IntentFilter downloadIntentFilter = new IntentFilter();
    downloadIntentFilter.addAction(ACTION_DOWNLOAD_FINISHED);
    registerReceiver(activity2DownloadBroadcastReceiver, downloadIntentFilter);

如果有的话,ACTION_DOWNLOAD_FINISHED 是com.example.intent.action. DOWNLOAD_FINISHED"。

服务1在接收器收到下载主管活动,显然播放了自己的习俗活动,但活动2似乎从未收到。我有什么错误? 是否在加工过程中播放意图是个问题? (我不认为如此——那是不合时宜的,正确吗?)

Update: 为了保证在接受广播的中间不会出现发送广播的问题,我修改了我的广播法,以便在主线上进行三秒广播:

    Log.i(getClass().getSimpleName(), "...ready to broadcast");     
    final Intent intent = new Intent(ACTION_DOWNLOAD_FINISHED).setData(checkNotNull(uri));
    mainThreadHandler.postDelayed(new Runnable()
    {
        public void run()
        {
            Log.i(getClass().getSimpleName(), "...broadcasting");
            sendBroadcast(intent);
            Log.i(getClass().getSimpleName(), "...broadcasted");                
        }
    }, 3000);
    Log.i(getClass().getSimpleName(), "...scheduled to broadcast");

如预期,该日志说:

...ready to broadcast
...scheduled to broadcast
...broadcasting
...broadcasted

但这项活动没有收到任何资料。请提供帮助。

Answer 1

Eureka! 我发现这句话! 问题是,我提供了我广播意向中的一份数据。甲型混凝土配对规则几乎变得复杂。如果你提供URI数据,那么你的意图过滤器必须指明一个相应的MMIS类型。

遗憾的是,尽管安乐文文件说,数据类型可以从数据URI中推断出来,但显然安乐团知道,file http://.../example.jpg 是一种形象。因此,这项工作没有:

intentFilter.addDataType("image/*");

然而,我不能具体指明一种类型,而是可以确定一个我接受的计划:

intentFilter.addDataScheme("file");

工作! 将我的广播限制在<代码>上: URIs,但随着时间的推移,它一直在运行。

Note that apparently I could manually specify the MIME type in the intent when I broadcast it, but that s too much trouble for now, as I m downloading images from Picasa so I already know that they are images (and don t care the specific MIME type). And if it gets too much trouble, I could ditch the whole setData() thing altogether and set an extra---but of course I want to do things the Right Way.

Answer 2

你是否把你的接受者列入你的活动?

<receiver
  android:name=".YourReceiver">
  <intent-filter>
    <action
      android:name="intent_name"></action>
  </intent-filter>
</receiver>

友情链接