Android: How to fill GridView programatically before starting transition?

Question

I have an MainActivity A, from which the user can select different items which are displayed in Activity B in a GridView. Between those Activities I have a Sliding-Transistion (Activity A slides out to the left, Activity B slides in from right)

My problem is, that if the animation starts, Activity B screen is not created complete (GridView items are added programmatically), so I see an empty screen sliding in from the right, which looks dump.

So my question: Is it possible to create/load Activity B before transition starts?

I attach some code, but all is pretty straight forward. Only the grid items consists of images with different states...

Activity A: start Intent (as usual)

 Intent intent = new Intent(this, SoundShareActivity.class);
 //...
 intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
 startActivity(intent);
 overridePendingTransition(anim.slide_in_from_right_to_left,
            anim.slide_out_to_left); 
 //anim defined in xml

Activity B: onCreate

 protected void onCreate(Bundle savedInstanceState) {
 //...
 mGridView = (GridView) findViewById(R.id.grid_view_sounds);
 mAdapter = new SoundAdapter(getApplicationContext(), THE_DATA);
 mGridView.setAdapter(mAdapter);
 mGridView.setOnItemClickListener( ... );
 mGridView.setLongClickable(true);
 mGridView.setOnItemLongClickListener(...);

Answer 1

1. Replace your activity to FragmentActivity
2. implement GridView and set the adapter in the fragment constructor/onCreateView functions
3. Replace Fragment with FragmentTransaction setCustomAnimations function.

very simple to implement

Answer 2

It is not possible using activities because you can't assign content to a View until it'll be inflated, which happens by setContentView() in Activity, usually in OnCreate(): so Activity has to be started first. But, since only one Activity instance could be active at one time, you can't do it while you are inside your first Activity.

Workaroud: use Fragments. You can have many instances of Fragments at one time, therefore, you can show to the user, for example, Fragment1 while loading Fragment2. ViewPager is often used in conjuction with fragments and it loads three pages by default, which means that while you see a page in ViewPager, previous and next pages and corresponding fragments are actually being loading or already loaded. You can use similar technique for your task.