How do I get the back button to close Activity without going back to the previous one (finish the app)?

Question

Activity login is MAIN and is used to log in to firebase.
If the user is already logged in goes straight to Activity from the main menu.

I wanted that, in the Activity of the main menu, when the user clicked the back button did not return to the Activity login and yes that the application ended.

Answer 1

In Activity login, right after the line you have startActivity() place finish();. This will close the Activity login by making sure that clicking the back does not return to it and the application is closed.

Anything like that:

Intent intent = new Intent(MainActivity.this, Main2Activity.class);
startActivity(intent);
finish();

The same can be achieved by Intent flags:

Intent intent = new Intent(MainActivity.this, Main2Activity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);

However, since there is only one Activity in the Stack, it is best to use the first method.

Answer 2

Have you ever tried to clear the back stack of Activities?

On the Internet that you do transition from login screen to other screen, add the flag: Intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

I hope it works!