How to properly close login page?-CodePudding

For example, first activity of app is MainActiviy which is basically 2 text fields (login and password) with a button. Pressing a button tells the database these text fields' data so it can tell the program if the user is in database and password is correct.

What I'm used to is to create a bool flag field saved in SharedPreference so the program knows i already logged in my app recently so it can open my second activity, but it seems like wrong and weird solution.

So, how do I properly login into my app in theory?

CodePudding user response：

This is wrong:

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

You should use "startActivity" before "finish()"

Correctly:

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

CodePudding user response：

Mikkel, Your approach with storing data using shared preferences is perfect but I have some suggestions which can make this solution better and robust.

First of all, you should check the sharePreference value inside a splash screen. Which checks for the login flag and launch the LoginActivity if a user is not logged in and launch the HomeActivity if a user is logged in.
Second, I would suggest using Androidx DataStore, which is a better version of shared preference and it can be asynchronous API so you can use it safely on the UI thread.

Don't forget to close your main activity after user login using the below code.

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

If you need an example to handle this stuff better here is the github-sample which can be very helpful.