Let's take another look at that line we just added.

Notice that we set the enter transition here.

So what does enter mean?

Let's see what other kinds of transitions we can set.

That's type getWindow.set.

And I'm just going start typing transition because it's going to show me.

There's a bunch of different ones we've got.

Enter.

Exit.

Reenter, and return.

Okay, so what do all of these mean?

When we start the album detail activity with a scene transition activity option.

The album detail activity will run the enter transition.

At the same time the album list activity will run its exit transition.

So if we want to customize how the album list goes away, we can set it there for

the exit transition.

Then when the user hits the back button a different pair of transitions

will be played.

The album detail activity will run its return transition.

And then the album list activity will run its re-enter transition.

To be honest, I've been confused by these four transitions for

quite a while until I drew the diagram you've just seen.

Now pause this video, and try to redraw the diagram yourself.

You'll have a much better time working with these transitions afterwards.

To put our theories into practice, let's customize some of the other transitions.

So let's set the return transitions.

So set return transition.

And we'll set it to a new fade transition.

And now, let's go to album list activity.

And we'll set it's exit transition to explode.

So here we have here we have inite transitions.

This is a different name from our starter files.

Let's just refactor this, I'm going to right click, refactor, rename.

We call this set up transitions to be consistent with what we have in our other

class.

Remember that old Boy Scout rule, always leave the campground, or

code cleaner than you found it.

Let's delete this re-enter transition.

We're not going to worry about that right now,

and will set the exit transition to a new explodes transition.

Haven't set to no like it was before it just means that no

transition will be used.

All right so guess what's going to happen here.

Let's run and see.

Okay and as you might expect.

The transitions look different now.

You can set the four types of transitions to any of the built in transitions or

use your own transition classes.

You can also set these to know which means no animation at all.

Also to save your effort and really tries its best to set proper defaults.

That's why we only needed to add one line in the first example.

Once we set the enter transition,

the system will use its reverse is the return transition.

Same story for exit and reenter transitions.