Login and logout sessions android

Question

I am developing an android app for the first time and I wanted to make the sessions for login and logout. I saw that most of the people suggested using SharedPreferences . But how can I check if the user logged out? If the user does not and clicks on my app, then the sign in page won't show up! The user can immediately go to the main page.

Answer 1

When the user login successfully call the setLogin function and set boolean as true and when the user come back then check the whether user isLogin() if it return true then redirect user to main page with Intent.

public boolean isLogin() {

        return pref.getBoolean("login", false);

    }

    public void setLogin(Boolean x) {
        SharedPreferences.Editor editor = pref.edit();
        editor.putBoolean("login", x);
        editor.commit();
    }