Implementar doble pulsación atrás para salir de la App en Android

Método para integrar un sistema de pulsación doble para salir de la App en Android. Para ello deberemos sobrescribir el evento de llamada onBackPresed()

class MainActivity : AppCompatActivity() {
 
    var lastClickTime: Long = 0
 
...
override fun onBackPressed() {
    if (lastClickTime.plus(2000L) > System.currentTimeMillis()) {
        super.onBackPressed()
    } else {
        Toast.makeText(this, getText(R.string.press_again_exit), Toast.LENGTH_SHORT).show()
        lastClickTime = System.currentTimeMillis()
    }
}

Si se usa el componente Navigation de componentes de arquitectura de Android

private var firstClickTime: Long = 0L
...
override fun onBackPressed() {
        if ((navController.graph.startDestination == navController.currentDestination?.id) && (!shouldBeExit())) {
            toast(R.string.double_back_pressed)
        } else super.onBackPressed()

    }

    private fun shouldBeExit(milSeconds: Long = 2000L): Boolean {
        return if (firstClickTime + milSeconds < System.currentTimeMillis()) {
            firstClickTime = System.currentTimeMillis()
            false
        } else true

    }

	@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();
	}
	}

view raw doubleBackPressed_drawableMenu.java hosted with ❤ by GitHub

Anuncio publicitario