Android

Question

我需要对 Chromecast 应用程序执行相同的操作 (com.google.android.apps.chromecast.app) "Mirror screen" 功能：

按应用要求 select chromecast 设备进行流式传输的自定义按钮，然后启动屏幕镜像到 selected chromecast 设备。

实际上，此功能并未在任何地方记录。我必须使用 Presentation class 吗？

阅读 Chromecast 应用程序的日志我发现了以下接收器应用程序 ID：

app id E8C28D3C
app name Backdrop

app id 674A0243
app name Screen Mirroring

我该怎么做？

这是我的代码：

    public class MainActivity extends ActionBarActivity
{

    private MediaRouter mMediaRouter;
    private MediaRouteSelector mMediaRouteSelector;
    private android.support.v7.media.MediaRouter.Callback mMediaRouterCallback;
    private CastDevice mSelectedDevice;
    private GoogleApiClient mApiClient;
    private Cast.Listener mCastClientListener;
    private ConnectionCallbacks mConnectionCallbacks;
    private ConnectionFailedListener mConnectionFailedListener;
    private boolean mWaitingForReconnect;
    private boolean mApplicationStarted;
    private String mSessionId;
    private DemoPresentation mPresentation;

    private final static String TAG = "CAST-APP";
    private String mAppID = "AE85BA70";
    private String mirroringAppID="674A0243";

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mMediaRouter = MediaRouter.getInstance(getApplicationContext());
        mMediaRouteSelector = new MediaRouteSelector.Builder()
                //.addControlCategory(MediaControlIntent.CATEGORY_LIVE_AUDIO)
                //.addControlCategory(MediaControlIntent.CATEGORY_LIVE_VIDEO)
                //.addControlCategory(MediaControlIntent.CATEGORY_REMOTE_PLAYBACK)
                //.addControlCategory(CastMediaControlIntent.categoryForCast(CastMediaControlIntent.DEFAULT_MEDIA_RECEIVER_APPLICATION_ID))
                .addControlCategory(CastMediaControlIntent.categoryForCast(mirroringAppID))
                .build();

        mMediaRouterCallback = new MyMediaRouterCallback();

        /*MediaRouteButton btn = (MediaRouteButton) findViewById(R.id.mediabutton);
        btn.setRouteSelector(mMediaRouteSelector);*/
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {

        super.onCreateOptionsMenu(menu);

        getMenuInflater().inflate(R.menu.menu_main, menu);

        MenuItem mediaRouteMenuItem = menu.findItem(R.id.media_route_menu_item);

        MediaRouteActionProvider mediaRouteActionProvider =
                (MediaRouteActionProvider) MenuItemCompat.getActionProvider(mediaRouteMenuItem);

        mediaRouteActionProvider.setRouteSelector(mMediaRouteSelector);

        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item)
    {
        int id = item.getItemId();
        return super.onOptionsItemSelected(item);
    }

    @Override
    protected void onResume() {
        super.onResume();
        mMediaRouter.addCallback(mMediaRouteSelector, mMediaRouterCallback,
                                 MediaRouter.CALLBACK_FLAG_REQUEST_DISCOVERY);
    }

    @Override
    protected void onPause() {
        if (isFinishing()) {
            mMediaRouter.removeCallback(mMediaRouterCallback);
        }
        super.onPause();
    }
/*
    @Override
    protected void onStart() {
        super.onStart();
        mMediaRouter.addCallback(mMediaRouteSelector, mMediaRouterCallback,
                                 MediaRouter.CALLBACK_FLAG_REQUEST_DISCOVERY);
    }

    @Override
    protected void onStop() {
        mMediaRouter.removeCallback(mMediaRouterCallback);
        super.onStop();
    }
*/

    private class MyMediaRouterCallback extends MediaRouter.Callback {

        @Override
        public void onRouteSelected(MediaRouter router, MediaRouter.RouteInfo info) {
            try
            {
                mSelectedDevice = CastDevice.getFromBundle(info.getExtras());
                String routeId = info.getId();

                mCastClientListener = new Cast.Listener()
                {
                    @Override
                    public void onApplicationStatusChanged()
                    {
                        if (mApiClient != null)
                        {
                            Log.d(TAG, "onApplicationStatusChanged: "
                                    + Cast.CastApi.getApplicationStatus(mApiClient));

                            //updatePresentation();

                        }
                    }

                    @Override
                    public void onVolumeChanged()
                    {
                        if (mApiClient != null)
                        {
                            Log.d(TAG, "onVolumeChanged: " + Cast.CastApi.getVolume(mApiClient));
                        }
                    }

                    @Override
                    public void onApplicationDisconnected(int errorCode)
                    {
                        teardown();
                    }
                };

                mConnectionCallbacks = new ConnectionCallbacks();
                mConnectionFailedListener = new ConnectionFailedListener();

                Cast.CastOptions.Builder apiOptionsBuilder = Cast.CastOptions
                        .builder(mSelectedDevice, mCastClientListener);

                mApiClient = new GoogleApiClient.Builder(getApplication())
                        .addApi(Cast.API, apiOptionsBuilder.build())
                        .addConnectionCallbacks(mConnectionCallbacks)
                        .addOnConnectionFailedListener(mConnectionFailedListener)
                        .build();

                mApiClient.connect();

            } catch (Exception e) {
                Log.d(TAG, "onRouteSelected " + e.getMessage());
            }

        }

        @Override
        public void onRouteUnselected(MediaRouter router, MediaRouter.RouteInfo info) {
            Log.d(TAG, "onRouteUnselected: info=" + info);
            teardown();
            //updatePresentation();
            mSelectedDevice = null;
        }

        @Override
        public void onRoutePresentationDisplayChanged(MediaRouter router, MediaRouter.RouteInfo info) {

            //updatePresentation();
        }
    }

    private void showPresentation()
    {
        DisplayManager displayManager = (DisplayManager) getSystemService(Context.DISPLAY_SERVICE);
        Display[] presentationDisplays = displayManager.getDisplays();

        Log.d("showPresentation", "Displays: " + String.valueOf(presentationDisplays.length));

        if (presentationDisplays.length > 0) {

            Log.d("showPresentation", "Display : " + presentationDisplays[0].getName());

            Display display = presentationDisplays[0];
            mPresentation = new DemoPresentation(this, display);
            mPresentation.show();
        }



        //updatePresentation();
    }

    private class ConnectionCallbacks implements
            GoogleApiClient.ConnectionCallbacks {
        @Override
        public void onConnected(Bundle connectionHint) {
            if (mWaitingForReconnect) {
                mWaitingForReconnect = false;
                //reconnectChannels();
                if ((connectionHint != null)
                        && connectionHint
                        .getBoolean(Cast.EXTRA_APP_NO_LONGER_RUNNING)) {
                    Log.d(TAG, "App  is no longer running");
                    teardown();
                }
            } else {
                try {
                    Cast.CastApi.launchApplication(mApiClient, mirroringAppID, false)
                            .setResultCallback(
                                    new ResultCallback<Cast.ApplicationConnectionResult>() {
                                        @Override
                                        public void onResult(Cast.ApplicationConnectionResult result) {
                                            Status status = result.getStatus();
                                            if (status.isSuccess()) {
                                                ApplicationMetadata applicationMetadata =
                                                        result.getApplicationMetadata();
                                                mSessionId = result.getSessionId();
                                                String applicationStatus = result.getApplicationStatus();
                                                boolean wasLaunched = result.getWasLaunched();

                                                mApplicationStarted = true;

                                            } else {
                                                teardown();
                                            }
                                        }
                                    });

                } catch (Exception e) {
                    Log.e(TAG, "Failed to launch application", e);
                }
            }
        }

        @Override
        public void onConnectionSuspended(int cause) {
            mWaitingForReconnect = true;
        }
    }

    private class ConnectionFailedListener implements
            GoogleApiClient.OnConnectionFailedListener {
        @Override
        public void onConnectionFailed(ConnectionResult result) {
            teardown();
        }
    }

    private void teardown() {
        Log.d(TAG, "teardown");
        if (mApiClient != null) {
            if (mApplicationStarted) {
                if (mApiClient.isConnected()  || mApiClient.isConnecting()) {
                    try {
                        Cast.CastApi.stopApplication(mApiClient, mSessionId);

                    } catch (Exception e) {
                        Log.e(TAG, "Exception while removing channel", e);
                    }
                    mApiClient.disconnect();
                }
                mApplicationStarted = false;
            }
            mApiClient = null;
        }
        mSelectedDevice = null;
        mWaitingForReconnect = false;
        mSessionId = null;
    }
}

Answer 1

你不能从你自己的应用程序中做到这一点，目前没有可供开发人员从他们的应用程序中启动投射镜像的 API，它应该由用户手动完成；这在未来可能会改变，但这是当前状态。

Answer 2

看来你只要不设置任何自定义Presentation screen就默认进行镜像:

https://developer.android.com/reference/android/media/MediaRouter.html#ROUTE_TYPE_LIVE_VIDEO

Android - 通过自定义应用将屏幕投射到 chromecast

Android - cast screen to chromecast via custom app

streaming

chromecast