我正在将我的应用程序从CastCompanionLibrary中移开，因为我需要支持更多流媒体设备，而且我的一些用户在使用Chromecast时遇到了问题。我删除了所有不必要的代码，并创建了一个应用程序，只是为了查看发现过程中发生了什么，并将其发送给其中一个用户，代码永远不会从媒体路由器获得任何回调。同时他们可以使用CastCompanionLibrary运行我的旧应用程序，它会发现Chromecast很好。
以下是我发送给用户的代码，它是一个自包含的类和布局：
public class MainActivity extends AppCompatActivity {
private static SimpleDateFormat TIME_ONLY = new SimpleDateFormat("HH:mm:ss.SSS");
private static Handler handler;
protected MediaRouter.Callback mMediaRouterCallback;
boolean isRunning = false;
private TextView logView;
private MediaRouter mMediaRouter;
private MediaRouteSelector mMediaRouteSelector;
private Timer removeRoutesTimer;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
logView = (TextView) findViewById(R.id.log);
Button sendLog = (Button)findViewById(R.id.send_log);
sendLog.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent send = new Intent(Intent.ACTION_SENDTO);
String uriText = "mailto:" + Uri.encode("myemail") +
"?subject=" + Uri.encode("Logs") +
"&body=" + Uri.encode(logView.getText().toString());
Uri uri = Uri.parse(uriText);
send.setData(uri);
startActivity(Intent.createChooser(send, "Send logs..."));
}
});
mMediaRouter = createMediaRouter(getApplicationContext());
mMediaRouterCallback = new MediaRouterCallback();
mMediaRouteSelector = new MediaRouteSelector.Builder()
.addControlCategory(CastMediaControlIntent.categoryForCast(
CastMediaControlIntent.DEFAULT_MEDIA_RECEIVER_APPLICATION_ID))
.build();
mMediaRouter.addCallback(mMediaRouteSelector, mMediaRouterCallback,
MediaRouter.CALLBACK_FLAG_REQUEST_DISCOVERY);
log("Discovery callback requested");
}
private void printRoutes() {
List<MediaRouter.RouteInfo> routes = mMediaRouter.getRoutes();
log("has routes " + routes.size() );
for(MediaRouter.RouteInfo info : routes){
log("has routes " + info.getName() +" - " + info.getDescription());
}
}
public static void runOnUI(Runnable runnable) {
if (handler == null) {
handler = new Handler(Looper.getMainLooper());
}
handler.post(runnable);
}
protected MediaRouter createMediaRouter(Context context) {
return MediaRouter.getInstance(context);
}
private void log(String start) {
Calendar cal = new GregorianCalendar();
String currentLog = logView.getText().toString();
logView.setText(currentLog + "\n" + TIME_ONLY.format(cal.getTime()) + " - " + start);
}
private class MediaRouterCallback extends MediaRouter.Callback {
@Override
public void onRouteAdded(MediaRouter router, MediaRouter.RouteInfo route) {
log("onRouteAdded - " + route.getName());
super.onRouteAdded(router, route);
}
@Override
public void onRouteChanged(MediaRouter router, MediaRouter.RouteInfo route) {
log("onRouteChanged - " + route.getName());
super.onRouteChanged(router, route);
}
@Override
public void onRoutePresentationDisplayChanged(MediaRouter router,
MediaRouter.RouteInfo route) {
log("onRoutePresentationDisplayChanged - [" + route.getName() + "] ["
+ route.getDescription() + "]");
super.onRoutePresentationDisplayChanged(router, route);
}
@Override
public void onRouteRemoved(final MediaRouter router, final MediaRouter.RouteInfo route) {
log("onRouteRemoved - " + route.getName());
super.onRouteRemoved(router, route);
}
@Override
public void onRouteVolumeChanged(MediaRouter router, final MediaRouter.RouteInfo route) {
super.onRouteVolumeChanged(router, route);
}
private void removeServices(final MediaRouter.RouteInfo route) {
log("removeServices - " + route.getName());
}
}
}
布局：
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity">
<Button
android:id="@+id/send_log"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:text="Send log"/>
<ScrollView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/send_log">
<TextView
android:id="@+id/log"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
</ScrollView>
</RelativeLayout>
以下是她寄给我的日志：
08:06:52.542 - Discovery callback requested
所以基本上没有调用回调方法。
这是我的网络中的日志，它工作正常（完全相同的apk）：
16:56:06.085 - Discovery callback requested
16:56:07.193 - onRouteAdded - Master bedroom
16:56:07.268 - onRouteAdded - Living room chromecast
16:56:07.274 - onRouteChanged - Master bedroom
16:56:07.332 - onRouteAdded - Gym
16:56:07.337 - onRouteChanged - Living room chromecast
16:56:07.341 - onRouteChanged - Master bedroom
16:56:07.405 - onRouteChanged - Gym
16:56:07.409 - onRouteChanged - Living room chromecast
16:56:07.413 - onRouteAdded - Basement east bedroom
16:56:07.417 - onRouteChanged - Master bedroom
16:56:07.517 - onRouteChanged - Gym
16:56:07.522 - onRouteChanged - Living room chromecast
16:56:07.526 - onRouteChanged - Basement east bedroom
16:56:07.530 - onRouteChanged - Master bedroom
正如您所看到的，发现Chromecast的代码非常简单，我看不出错误在哪里。据我所知，这些都是所需的所有行：
mMediaRouter = createMediaRouter(getApplicationContext());
mMediaRouterCallback = new MediaRouterCallback();
mMediaRouteSelector = new MediaRouteSelector.Builder()
.addControlCategory(CastMediaControlIntent.categoryForCast(
CastMediaControlIntent.DEFAULT_MEDIA_RECEIVER_APPLICATION_ID))
.build();
mMediaRouter.addCallback(mMediaRouteSelector, mMediaRouterCallback,
MediaRouter.CALLBACK_FLAG_REQUEST_DISCOVERY);
如果我将MediaRouter.CALLBACK_FLAG_REQUEST_DISCOVERY更改为MediaRouter.CALLBACK_FLAG_FORCE_DISCOVERY，我应该为此特定用户添加该功能，那么它可以正常工作。
那么我的发现代码有什么问题？
感谢。