Android: sistema doble pulsación para salir

Readme.md

Pulsar dos veces atrás para salir

Método para integrar un sistema de pulsación doble para salir de la app en Android. Para ello debermos sobrescrivir el evento de llamanda onBackPresed()

  private long firstClickTime;
  ...
  @Override
  public void onBackPressed() {
    if (firstClickTime + Constants.TIME_INTERVAL > System.currentTimeMillis()) {
        super.onBackPressed();
        return;
    } else {
        Toast.makeText(this, getString(R.string.double_back_pressed), Toast.LENGTH_SHORT).show();
    }
    firstClickTime = System.currentTimeMillis();

Si la app tiene un drawableMenu

  @Override
  public void onBackPressed() {
      DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
      if (drawer.isDrawerOpen(GravityCompat.START)) {
          drawer.closeDrawer(GravityCompat.START);
      } else {

          if (firstClickTime + Constants.TIME_INTERVAL > System.currentTimeMillis()) {
              super.onBackPressed();
              return;
          } else {
              Toast.makeText(this, getString(R.string.double_back_pressed), Toast.LENGTH_SHORT).show();
          }
          firstClickTime = System.currentTimeMillis();

      }
  }