我有一个MediaRouterandroid应用程序的问题，我遵循了android API指南MediaRouter但是当我运行应用程序时，工具栏上没有出现任何按钮。
public class MediaRouterPlaybackActivity extends AppCompatActivity {
private MediaRouteSelector mSelector;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.miracast);
Toolbar myToolbar = (Toolbar) findViewById(R.id.my_toolbar);
setSupportActionBar(myToolbar);
// Create a route selector for the type of routes your app supports.
mSelector = new MediaRouteSelector.Builder()
// These are the framework-supported intents
.addControlCategory(MediaControlIntent.CATEGORY_REMOTE_PLAYBACK)
.build();
}
@Override
public boolean onCreateOptionsMenu(Menu menu){
super.onCreateOptionsMenu(menu);
// Inflate the menu and configure the media router action provider.
getMenuInflater().inflate(R.menu.mediarouter, menu);
// Attach the MediaRouteSelector to the menu item
MenuItem mediaRouteMenuItem = menu.findItem(R.id.media_route_menu_item);
MediaRouteActionProvider mediaRouteActionProvider =
(MediaRouteActionProvider) MenuItemCompat.getActionProvider(
mediaRouteMenuItem);
// Attach the MediaRouteSelector that you built in onCreate()
mediaRouteActionProvider.setRouteSelector(mSelector);
// Return true to show the menu.
return true;
}
}
这是工具栏的代码：
<android.support.v7.widget.Toolbar
android:id="@+id/my_toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="#4696e5"
android:elevation="4dp"
android:theme="@style/ThemeOverlay.AppCompat.ActionBar"
app:popupTheme="@style/Theme.AppCompat"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="60dp" />