try this:
public boolean onOptionsItemSelected(MenuItem item) {
TextView lblDateTime = (TextView) findViewById(R.id.lblDateTime);
lblDateTime.setText(item.getItemId());
boolean result = false;
switch (item.getItemId()) {
case R.id.mnabout:
lblDateTime.setText("About selected");
result = true;
break;
case R.id.mnexit:
if(mediaplayer!=null && mediaplayer.isplaying()){
mediaplayer.stop();
}
result = true;
this.finish();
break;
default:
result = super.onOptionsItemSelected(item);
break;
}
return result;
}