How to exit the android application on backpress?

Question

The situation could be like say, I\'ve 5 activities. Say Main activity, Activity 1, Activity 2, Activity 3 and Activity 4.

One can use the Activity 1,2,3 & 4 dir

Answer 1

It is a good code practice to write double back press to exit Main Activity.

boolean doubleBackToExitPressedOnce = false;

@Override
public void onBackPressed() {
if (doubleBackToExitPressedOnce) {
    super.onBackPressed();
    return;
}

this.doubleBackToExitPressedOnce = true;
Toast.makeText(this, "Please click BACK again to exit", Toast.LENGTH_SHORT).show();

new Handler().postDelayed(new Runnable() {

    @Override
    public void run() {
        doubleBackToExitPressedOnce=false;                       
    }
}, 2000);

}