Android call TTS in BroadcastReceiver
I need to call TTS service within subclass of BroadcastReceiver. When I am implement 开发者_StackOverflow社区that class from OnInitListener, it gave run-time error.
Is there any other-way to implement TTS within BroadcastReceiver?
Thank You,
Sorry Code:
public class TextApp extends BroadcastReceiver implements OnInitListener {
private TextToSpeech tts;
private String message = "Hello";
@Override
public void onReceive(Context context, Intent intent) {
tts = new TextToSpeech(context, this);
message = "Hello TTS";
}
@Override
public void onInit(int status) {
if (status == TextToSpeech.SUCCESS)
{
tts.speak(message, TextToSpeech.QUEUE_FLUSH, null);
}
}
}
Your code didn't work on :
tts = new TextToSpeech(context, this);
Context on BroadcastReceiver is a "restricted context". It means you cannot start service on context in BroadcastReceiver. Because TTS is a service, so it doesn't call anyting.
The Best Solutions is you start another intent on BroadcastReceiver with activity that call the service.
public void onReceive(Context context, Intent intent) {
....
Intent speechIntent = new Intent();
speechIntent.setClass(context, ReadTheMessage.class);
speechIntent.putExtra("MESSAGE", message.getMessageBody().toString());
speechIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);
context.startActivity(speechIntent);
....
}
And then on the activity you call the TTS service with parameter from extras
public class ReadTheMessage extends Activity implements OnInitListener,OnUtteranceCompletedListener {
private TextToSpeech tts = null;
private String msg = "";
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Intent startingIntent = this.getIntent();
msg = startingIntent.getStringExtra("MESSAGE");
tts = new TextToSpeech(this,this);
}
@Override
protected void onDestroy() {
super.onDestroy();
if (tts!=null) {
tts.shutdown();
}
}
// OnInitListener impl
public void onInit(int status) {
tts.speak(msg, TextToSpeech.QUEUE_FLUSH, null);
}
// OnUtteranceCompletedListener impl
public void onUtteranceCompleted(String utteranceId) {
tts.shutdown();
tts = null;
finish();
}
}
You can try using either JobIntentService (Post Android-O) or IntentService to invoke TTS from Broadcast receiver. It has less overhead than launching an activity for the sake of giving TTS a correct context. Note that you cannot give a broadcast receiver's context to TTS.
Here is my code snippet where I acheived same thing using JobIntentService.
Inside your custom Broadcast receiver's onReceive() invoke your custom JobIntentService like this:
Intent speechIntent = new Intent();
speechIntent.putExtra("MESSAGE", "Bluetooth is on.");
MySpeakService.enqueueWork(context, speechIntent);
And MySpeakService.java is this:
import android.content.Context;
import android.content.Intent;
import android.speech.tts.TextToSpeech;
import android.support.annotation.NonNull;
import android.support.v4.app.JobIntentService;
public class MySpeakService extends JobIntentService {
private TextToSpeech mySpeakTextToSpeech = null;
private boolean isSafeToDestroy = false;
public static void enqueueWork(Context context, Intent intent) {
enqueueWork(context, MySpeakService.class, 1, intent);
}
@Override
protected void onHandleWork(@NonNull Intent intent) {
String message = intent.getStringExtra("MESSAGE");
mySpeakTextToSpeech = new TextToSpeech(getApplicationContext(), new TextToSpeech.OnInitListener() {
@Override
public void onInit(int status) {
mySpeakTextToSpeech.speak(message, TextToSpeech.QUEUE_ADD, null, null);
while (mySpeakTextToSpeech.isSpeaking()) {
}
isSafeToDestroy = true;
}
});
}
@Override
public void onDestroy() {
if (isSafeToDestroy) {
if (mySpeakTextToSpeech != null) {
mySpeakTextToSpeech.shutdown();
}
super.onDestroy();
}
}
}
Al Zil answer is not totally correct. Android TTS is a bounded service. Broadcast receivers truly has a limited context but they can't bind themselves to any service. However, they can START a service. Starting the tts from activity is ok, but if you don't need UI you can also initialize it from a service. Look at this answer to see how it's done
Good luck.
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