Android app login flow

Question

How can I ask the user for login without flicker my MainActivity?

I have two activities: LoginActivity and MainActivity. Let's start with my AndroidManifest.xml:

<activity 
    android:name=".app.MainActivity"
    android:logo="@drawable/logo_bw" >
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
</activity>

The MainActivity is responsible to check if the user is logged in:

@Override
protected void onResumeFragments() {
    super.onResumeFragments();
    if (isAuthenticated()) {
        showFragment(HOME, false);
    } else {
        startActivityForResult(new Intent(this, LoginActivity.class), LOGIN_REQUEST);
    }
}

This code flickers the MainActivity before showing the LoginActivity when the user is not logged in (eg. the first time using my app).

I think I have two options to manage this:

1) transform LoginActivity into LoginFragment and let MainActivity show the correct fragment (as in this example from facebook )

But I think fragments are miused at this facebook sample, because "A Fragment represents a behavior or a portion of user interface in an Activity." (see the documentation ) and the Login is not a portion of MainActivity user interface, has it's own lifecycle. Futhermore, I'm not considering login dialog.

2) create an "invisible" activity that redirects to the correct activity as suggested here

I didn`t understand what does "invisible activity" mean, because I tried out this solution and what happens is a flicker of the EntryActivity before showing the next activity. And it all begins again...

Answer 1

I ended up doing the suggestion 2 from my question. I created an EntryActivity with a blank layout that flickers quickly before showing the LoginActivity.