you can use SuperToast for showing toast to user
of other way you can show a dialog box non cancelable and put it in a thread in 30 sec dismiss it but you must handle views and context and this is so hard job
you can try this code maybe work for you :
private Toast mToastToShow;
public void showToast(View view) {
// Set the toast and duration
int toastDurationInMilliSeconds = 10000;
mToastToShow = Toast.makeText(this, "Hello world, I am a toast.",
Toast.LENGTH_LONG);
// Set the countdown to display the toast
CountDownTimer toastCountDown;
toastCountDown = new CountDownTimer(toastDurationInMilliSeconds,
1000 /*Tick duration*/) {
public void onTick(long millisUntilFinished) {
mToastToShow.show();
}
public void onFinish() {
mToastToShow.cancel();
}
};
// Show the toast and starts the countdown
mToastToShow.show();
toastCountDown.start();
}