} }; OnClickListener threeButtonListner = new OnClickListener() { public void onClick(View v) { ToneGenerator tg = new ToneGenerator( AudioManager.STREAM_SYSTEM, 100); tg.startTone(ToneGenerator.TONE_DTMF_3, 100); tg.release(); } }; OnClickListener fourButtonListner = new OnClickListener() { public void onClick(View v) { ToneGenerator tg = new ToneGenerator( AudioManager.STREAM_SYSTEM, 100); tg.startTone(ToneGenerator.TONE_DTMF_4, 100); tg.release();