我正在
尝试调用虚方法＆＃39; void android.support.v7.app.MediaRouteActionProvider.setRouteSelector（android.support.v7.media.MediaRouteSelector）＆＃39; 在空对象引用上
当我想要为我的应用程序包含演员支持时，我已经在一个单独的项目中创建了所有内容现在我只想将所有内容传输到我的应用程序而且我得到了这个例外。我无法看到我在哪里制作错误。 这是我的代码：
......
private MediaRouter mMediaRouter;
private MediaRouteSelector mMediaRouteSelector;
private MediaRouter.Callback mMediaRouterCallback;
private CastDevice mSelectedDevice;
private GoogleApiClient mApiClient;
private Cast.Listener mCastListener;
private GoogleApiClient.ConnectionCallbacks mConnectionCallbacks;
private ConnectionFailedListener mConnectionFailedListener;
private HelloWorldChannel mHelloWorldChannel;
private boolean mApplicationStarted;
private boolean mWaitingForReconnect;
private String mSessionId;
@Override
protected void onCreate(Bundle savedInstanceState) {
//for transaltion
SharedPreferences LengPref = getSharedPreferences("language",
MODE_PRIVATE);
String langStr = LengPref.getString("lang", "");
String languageToLoad = langStr;
Locale locale = new Locale(languageToLoad);
Locale.setDefault(locale);
Configuration config = new Configuration();
config.locale = locale;
getBaseContext().getResources().updateConfiguration(config, null);
// for transaltion
super.onCreate(savedInstanceState);
// Configure Cast device discovery
mMediaRouter = MediaRouter.getInstance(getApplicationContext());
mMediaRouteSelector = new MediaRouteSelector.Builder()
.addControlCategory(CastMediaControlIntent.categoryForCast(getResources()
.getString(R.string.app_id))).build();
mMediaRouterCallback = new MyMediaRouterCallback();
.....
}
private class MyMediaRouterCallback extends MediaRouter.Callback {
@Override
public void onRouteSelected(MediaRouter router, MediaRouter.RouteInfo info) {
//Log.d(TAG, "onRouteSelected");
// Handle the user route selection.
mSelectedDevice = CastDevice.getFromBundle(info.getExtras());
launchReceiver();
}
@Override
public void onRouteUnselected(MediaRouter router, MediaRouter.RouteInfo info) {
//Log.d(TAG, "onRouteUnselected: info=" + info);
teardown(false);
mSelectedDevice = null;
}
}
.......
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu items for use in the action bar
MenuInflater inflater = getMenuInflater();
//getMenuInflater().inflate(R.menu.main, menu);
if (workoutTypeFinal == 0) {
inflater.inflate(R.menu.workout_menu, menu);
} else if (workoutTypeFinal == 2 || workoutTypeFinal == 3) {
inflater.inflate(R.menu.workout_menu, menu);
} else {
//ovo je ako je next next tip
inflater.inflate(R.menu.workout_menu_2, menu);
}
MenuItem mediaRouteMenuItem = menu.findItem(R.id.media_route_menu_item);
MediaRouteActionProvider mediaRouteActionProvider
= (MediaRouteActionProvider) MenuItemCompat
.getActionProvider(mediaRouteMenuItem);
// Set the MediaRouteActionProvider selector for device discovery.
mediaRouteActionProvider.setRouteSelector(mMediaRouteSelector);
mOptionsMenu = menu;
return super.onCreateOptionsMenu(menu);
}
.....
@Override
protected void onStop() {
mMediaRouter.removeCallback(mMediaRouterCallback);
super.onStop();
if (hasTimer == true) {
timer5.cancel();
timer2.cancel();
}
if (workoutTypeFinal == 0) {
//inflater.inflate(R.menu.workout_menu, menu);
if (isTimer1 == true) {
timer1.cancel();
//timer5.cancel();
//mp.stop();
} else if (isTimer2 == true) {
timer2.cancel();
timer5.cancel();
if (isMusic == true) {
mp.stop();
} else {
}
} else if (isTimer3 == true) {
timer3.cancel();
timer5.cancel();
mp.stop();
} else if (isTimer4 == true) {
timer4.cancel();
timer5.cancel();
mp.stop();
}
} else if (workoutTypeFinal == 2) {
//inflater.inflate(R.menu.workout_menu, menu);
} else {
//ovo je ako je next next tip
//inflater.inflate(R.menu.workout_menu_2, menu);
}
}
@Override
protected void onPause() {
super.onPause();
//pausedVoid=false;
if (workoutTypeFinal == 0) {
if (pausedVoid == true) {
} else {
pauseTime();
}
} else if (workoutTypeFinal == 2) {
if (pausedVoid == true) {
} else {
pauseTime();
}
//asd
} else {
//ovo je ako je next next tip
}
}
@Override
protected void onDestroy() {
teardown(true);
super.onDestroy();
if (hasTimer == true) {
timer5.cancel();
timer2.cancel();
}
if (workoutTypeFinal == 0) {
//inflater.inflate(R.menu.workout_menu, menu);
if (isTimer1 == true) {
timer1.cancel();
//timer5.cancel();
//mp.stop();
} else if (isTimer2 == true) {
timer2.cancel();
timer5.cancel();
if (isMusic == true) {
mp.stop();
} else {
}
} else if (isTimer3 == true) {
timer3.cancel();
timer5.cancel();
mp.stop();
} else if (isTimer4 == true) {
timer4.cancel();
timer5.cancel();
mp.stop();
}
} else if (workoutTypeFinal == 2) {
//inflater.inflate(R.menu.workout_menu, menu);
if (isTimer1 == true) {
timer1.cancel();
//timer5.cancel();
//mp.stop();
} else if (isTimer2 == true) {
timer2.cancel();
timer5.cancel();
if (isMusic == true) {
mp.stop();
} else {
}
} else if (isTimer3 == true) {
timer3.cancel();
timer5.cancel();
mp.stop();
} else if (isTimer4 == true) {
timer4.cancel();
timer5.cancel();
mp.stop();
}
} else {
//ovo je ako je next next tip
}
}
@Override
protected void onResume() {
super.onResume();
}
........
@Override
protected void onStart() {
super.onStart();
// Start media router discovery
mMediaRouter.addCallback(mMediaRouteSelector, mMediaRouterCallback,
MediaRouter.CALLBACK_FLAG_REQUEST_DISCOVERY);
}
//Chromecast
/**
* Start the receiver app
*/
private void launchReceiver() {
try {
mCastListener = new Cast.Listener() {
@Override
public void onApplicationDisconnected(int errorCode) {
Log.d(TAG, "application has stopped");
teardown(true);
}
};
// Connect to Google Play services
mConnectionCallbacks = new ConnectionCallbacks();
mConnectionFailedListener = new ConnectionFailedListener();
Cast.CastOptions.Builder apiOptionsBuilder = Cast.CastOptions
.builder(mSelectedDevice, mCastListener);
mApiClient = new GoogleApiClient.Builder(this)
.addApi(Cast.API, apiOptionsBuilder.build())
.addConnectionCallbacks(mConnectionCallbacks)
.addOnConnectionFailedListener(mConnectionFailedListener)
.build();
mApiClient.connect();
} catch (Exception e) {
Log.e(TAG, "Failed launchReceiver", e);
}
}
/**
* Google Play services callbacks
*/
private class ConnectionCallbacks implements GoogleApiClient.ConnectionCallbacks {
@Override
public void onConnected(Bundle connectionHint) {
Log.d(TAG, "onConnected");
if (mApiClient == null) {
// We got disconnected while this runnable was pending
// execution.
return;
}
try {
if (mWaitingForReconnect) {
mWaitingForReconnect = false;
// Check if the receiver app is still running
if ((connectionHint != null)
&& connectionHint.getBoolean(Cast.EXTRA_APP_NO_LONGER_RUNNING)) {
Log.d(TAG, "App is no longer running");
teardown(true);
} else {
// Re-create the custom message channel
try {
Cast.CastApi.setMessageReceivedCallbacks(
mApiClient,
mHelloWorldChannel.get_messageBus_round(),
mHelloWorldChannel);
Cast.CastApi.setMessageReceivedCallbacks(
mApiClient,
mHelloWorldChannel.get_messageBus_current_text(),
mHelloWorldChannel);
Cast.CastApi.setMessageReceivedCallbacks(
mApiClient,
mHelloWorldChannel.get_messageBus_current_exercise(),
mHelloWorldChannel);
Cast.CastApi.setMessageReceivedCallbacks(
mApiClient,
mHelloWorldChannel.get_messageBus_current_time(),
mHelloWorldChannel);
} catch (IOException e) {
Log.e(TAG, "Exception while creating channel", e);
}
}
} else {
// Launch the receiver app
Cast.CastApi.launchApplication(mApiClient, getString(R.string.app_id), false)
.setResultCallback(
new ResultCallback<Cast.ApplicationConnectionResult>() {
@Override
public void onResult(
Cast.ApplicationConnectionResult result) {
Status status = result.getStatus();
Log.d(TAG,
"ApplicationConnectionResultCallback.onResult:"
+ status.getStatusCode());
if (status.isSuccess()) {
ApplicationMetadata applicationMetadata = result
.getApplicationMetadata();
mSessionId = result.getSessionId();
String applicationStatus = result
.getApplicationStatus();
boolean wasLaunched = result.getWasLaunched();
Log.d(TAG, "application name: "
+ applicationMetadata.getName()
+ ", status: " + applicationStatus
+ ", sessionId: " + mSessionId
+ ", wasLaunched: " + wasLaunched);
mApplicationStarted = true;
// Create the custom message
// channel
mHelloWorldChannel = new HelloWorldChannel();
try {
Cast.CastApi.setMessageReceivedCallbacks(
mApiClient,
mHelloWorldChannel.get_messageBus_round(),
mHelloWorldChannel);
Cast.CastApi.setMessageReceivedCallbacks(
mApiClient,
mHelloWorldChannel.get_messageBus_current_text(),
mHelloWorldChannel);
Cast.CastApi.setMessageReceivedCallbacks(
mApiClient,
mHelloWorldChannel.get_messageBus_current_exercise(),
mHelloWorldChannel);
Cast.CastApi.setMessageReceivedCallbacks(
mApiClient,
mHelloWorldChannel.get_messageBus_current_time(),
mHelloWorldChannel);
} catch (IOException e) {
Log.e(TAG, "Exception while creating channel",
e);
}
// set the initial instructions
// on the receiver
//Salje Talk to me text
//sendMessage(getString(R.string.instructions),0);
} else {
Log.e(TAG, "application could not launch");
teardown(true);
}
}
});
}
} catch (Exception e) {
Log.e(TAG, "Failed to launch application", e);
}
}
@Override
public void onConnectionSuspended(int cause) {
Log.d(TAG, "onConnectionSuspended");
mWaitingForReconnect = true;
}
}
/**
* Google Play services callbacks
*/
private class ConnectionFailedListener implements
GoogleApiClient.OnConnectionFailedListener {
@Override
public void onConnectionFailed(ConnectionResult result) {
Log.e(TAG, "onConnectionFailed ");
teardown(false);
}
}
/**
* Tear down the connection to the receiver
*/
private void teardown(boolean selectDefaultRoute) {
Log.d(TAG, "teardown");
if (mApiClient != null) {
if (mApplicationStarted) {
if (mApiClient.isConnected() || mApiClient.isConnecting()) {
try {
Cast.CastApi.stopApplication(mApiClient, mSessionId);
if (mHelloWorldChannel != null) {
Cast.CastApi.removeMessageReceivedCallbacks(
mApiClient,
mHelloWorldChannel.get_messageBus_round());
Cast.CastApi.removeMessageReceivedCallbacks(
mApiClient,
mHelloWorldChannel.get_messageBus_current_text());
Cast.CastApi.removeMessageReceivedCallbacks(
mApiClient,
mHelloWorldChannel.get_messageBus_current_exercise());
Cast.CastApi.removeMessageReceivedCallbacks(
mApiClient,
mHelloWorldChannel.get_messageBus_current_time());
mHelloWorldChannel = null;
}
} catch (IOException e) {
Log.e(TAG, "Exception while removing channel", e);
}
mApiClient.disconnect();
}
mApplicationStarted = false;
}
mApiClient = null;
}
if (selectDefaultRoute) {
mMediaRouter.selectRoute(mMediaRouter.getDefaultRoute());
}
mSelectedDevice = null;
mWaitingForReconnect = false;
mSessionId = null;
}
/**
* Send a text message to the receiver
*/
private void sendMessage(String message,int case_) {
if (mApiClient != null && mHelloWorldChannel != null) {
try {
//Salje stranici message od text speacha
if(case_ == 0){
Cast.CastApi.sendMessage(mApiClient, mHelloWorldChannel.get_messageBus_round(), message).setResultCallback(
new ResultCallback<Status>() {
@Override
public void onResult(Status result) {
if (!result.isSuccess()) {
Log.e(TAG, "Sending message failed");
}
}
});
}else if(case_ == 1){
Cast.CastApi.sendMessage(mApiClient, mHelloWorldChannel.get_messageBus_current_text(), message).setResultCallback(
new ResultCallback<Status>() {
@Override
public void onResult(Status result) {
if (!result.isSuccess()) {
Log.e(TAG, "Sending message failed");
}
}
});
}else if(case_ == 2){
Cast.CastApi.sendMessage(mApiClient, mHelloWorldChannel.get_messageBus_current_exercise(), message).setResultCallback(
new ResultCallback<Status>() {
@Override
public void onResult(Status result) {
if (!result.isSuccess()) {
Log.e(TAG, "Sending message failed");
}
}
});
}else if(case_ == 3){
Cast.CastApi.sendMessage(mApiClient, mHelloWorldChannel.get_messageBus_current_time(), message).setResultCallback(
new ResultCallback<Status>() {
@Override
public void onResult(Status result) {
if (!result.isSuccess()) {
Log.e(TAG, "Sending message failed");
}
}
});
}
} catch (Exception e) {
Log.e(TAG, "Exception while sending message", e);
}
} else {
//Toast.makeText(MainActivity.this, message, Toast.LENGTH_SHORT).show();
}
}
/**
* Custom message channel
*/
class HelloWorldChannel implements Cast.MessageReceivedCallback {
/**
* @return custom namespace
*/
public String get_messageBus_round(){
return getString(R.string.messageBus_round);
}
public String get_messageBus_current_text(){
return getString(R.string.messageBus_current_text);
}
public String get_messageBus_current_exercise(){
return getString(R.string.messageBus_current_exercise);
}
public String get_messageBus_current_time(){
return getString(R.string.messageBus_current_time);
}
/*
* Receive message from the receiver app
*/
@Override
public void onMessageReceived(CastDevice castDevice, String namespace,
String message) {
Log.d(TAG, "onMessageReceived: " + message);
}
}
}
答案 0 :(得分：1)
问题出在菜单中，这是菜单的样子：
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
tools:context="com.example.casthelloworld.MainActivity" >
<item
android:id="@+id/media_route_menu_item"
android:title="@string/media_route_menu_title"
app:actionProviderClass="android.support.v7.app.MediaRouteActionProvider"
app:showAsAction="always"/>
</menu>