我想发现一个Chromecast设备并调节音量。
import com.google.cast.CastContext;
Context applicationContext = …; CastContext castContext = new
CastContext(applicationContext);
< android.support.v7.app.MediaRouteButton
android:id="@+id/media_route_button"
android:mediaRouteTypes="user"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="visible" />
import com.google.cast.CastContext;
import com.google.cast.CastDevice;
import com.google.cast.MediaRouteAdapter;
import com.google.cast.MediaRouteHelper;
import com.google.cast.MediaRouteStateChangeListener;
import android.support.v4.app.FragmentActivity;
import android.support.v7.app.MediaRouteButton;
import android.support.v7.media.MediaRouteSelector;
import android.support.v7.media.MediaRouter;
import android.support.v7.media.MediaRouter.RouteInfo;
public class MyCastActivity extends FragmentActivity implements MediaRouteAdapter {
private MediaRouteButton mMediaRouteButton;
private MediaRouter mMediaRouter;
private MediaRouteSelector mMediaRouteSelector;
private MediaRouter.Callback mMediaRouterCallback;
private CastDevice mSelectedDevice;
private MediaRouteStateChangeListener mRouteStateListener;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.my_cast_activity);
mMediaRouteButton = (MediaRouteButton) findViewById(R.id.media_route_button);
CastContext
。
mCastContext = new CastContext(getApplicationContext());
通过调用MediaRouteHelper.registerMinimalMediaRouteProvider
()方法,传递实现MediaRouteAdapter
接口的对象来注册MinimalCastMediaRouteProvider
。
MediaRouteHelper.registerMinimalMediaRouteProvider(mCastContext, this);
mMediaRouter = MediaRouter.getInstance(getApplicationContext());
MediaRouteHelper.buildMediaRouteSelector()
构建一个MediaRouteSelector
。此方法有两种形式:第一种不带参数,第二种带有接收器应用程序名称和/或消息协议列表。后者用于执行与SDK的ApplicationSupportFilterListener
相同的设备过滤。mMediaRouteSelector = MediaRouteHelper.buildMediaRouteSelector( MediaRouteHelper.CATEGORY_CAST);
mMediaRouteButton.setRouteSelector(mMediaRouteSelector);
MediaRouter.Callback
并将其添加到MediaRouter
中,
通过向MediaRouter
传递CALLBACK_FLAG_REQUEST_DISCOVERY
来启动发现。
当用户在GUI选取器中选择或取消选择路由时,该回调接口上相应的方法将被调用。在
mMediaRouterCallback = new MyMediaRouterCallback(); } @Override protected void onStart() { super.onStart(); mMediaRouter.addCallback(mMediaRouteSelector, mMediaRouterCallback, MediaRouter.CALLBACK_FLAG_REQUEST_DISCOVERY); } @Override protected void onStop() { mMediaRouter.removeCallback(mMediaRouterCallback); super.onStop(); } @Override protected void onDestroy() { MediaRouteHelper.unregisterMediaRouteProvider(mCastContext); mCastContext.dispose(); super.onDestroy(); }
MediaRouter.Callback
的onRouteSelected()
回调中,调用MediaRouteHelper.requestCastDeviceForRoute()
函数,获取所选择媒体路线的CastDevice对象,以及需要在路线音量或连接状态更改时通知的MediaRouteStateChangeListener
。
private class MyMediaRouterCallback extends MediaRouter.Callback { @Override public void onRouteSelected(MediaRouter router, RouteInfo route) { MediaRouteHelper.requestCastDeviceForRoute(route); } @Override public void onRouteUnselected(MediaRouter router, RouteInfo route) { mSelectedDevice = null; mRouteStateListener = null; } } // MediaRouteAdapter implementation @Override public void onDeviceAvailable(CastDevice device, MediaRouteStateChangeListener listener) { mSelectedDevice = device; mRouteStateListener = listener; } @Override public void onSetVolume(double volume) { // Handle volume change. } @Override public void onUpdateVolume(double delta) { // Handle volume change. }
}