java - speak failed:not bound to tts engine -

issue : speak failed:not bound tts engine

i implementing texttospeech functionality. getting exception speak failed: not bound tts engine. implementing async task it. async task reading mail. , want convert mail body speech.

package com.example.trynot;  import android.os.bundle; import android.app.activity; import android.view.menu; import java.util.locale;  import com.example.trynot.mainactivity.readmailsample;  import android.app.activity; import android.os.bundle; import android.speech.tts.texttospeech; import android.util.log; import android.view.view; import android.widget.button; import android.widget.edittext; public class notify extends activity implements texttospeech.oninitlistener { /** called when activity first created. */   public texttospeech tts = new texttospeech(mainactivity.c, notify.this);   public notify()  {      system.out.println("inside constructor");      speakout();  }  @override public void ondestroy() { // don't forget shutdown tts! if (tts != null) {     tts.stop();     tts.shutdown(); } super.ondestroy(); }  @override public void oninit(int status) { system.out.println("inside init"); if (status == texttospeech.success) {      int result = tts.setlanguage(locale.us);     tts.speak(mainactivity.readmailsample.command, texttospeech.queue_flush, null);     if (result == texttospeech.lang_missing_data             || result == texttospeech.lang_not_supported) {         log.e("tts", "this language not supported");     } else {          speakout();     }  } else {     log.e("tts", "initilization failed!"); }  }  private void speakout() {     system.out.println("inside speak out"); tts.speak(mainactivity.readmailsample.command, texttospeech.queue_flush, null); }   } 

you should move instatiation of tts engine instance oncreate, line:

public texttospeech tts = new texttospeech(mainactivity.c, notify.this); 

change to:

public texttospeech tts; 

and add inside oncreate:

    tts = new texttospeech(mainactivity.c, notify.this); 

and - whats important - not use constructor in activity derived classes:

 public notify()  {      system.out.println("inside constructor");      speakout();  } 

should oncreate:

 @override  protected void oncreate (bundle savedinstancestate)  {      super.oncreate(savedinstancestate);      //speakout(); // here tts not yet initialized, call in oninit on success      //tts = new texttospeech(mainactivity.c, notify.this); // whats mainactivity.c?      tts = new texttospeech(this, this);  }