Android change background image with fade in/out animation

You can use relativeLayout, and add one layer of background view which set both height and width match_parent. All other UI element should put on top of this view. In your code. Define fadeOut and fadeIn animation. Find that background view by id, then do this:

 xxxBackground.startAnimation(fadeOut);
 xxxBackground.setBackgroundResource(R.drawable.your_random_pic);
 xxxBackground.startAnimation(fadeIn);

You can use some interpolator to tune the performance.

You need to call these codes.

First, you have to make two xml files for fade in & out animation like this.

fade_in.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
<alpha
        android:fromAlpha="0.0"
        android:toAlpha="1.0"
        android:fillAfter="true"
        android:duration="2000"
        />
</set>

fade_out.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
<alpha
        android:fromAlpha="1.0"
        android:toAlpha="0.0"
        android:fillAfter="true"
        android:duration="2000"
        />
</set>

Second, you have to run animation of imageView like below and also you have to set AnimationListener to change fadeout when fadein finish.

Animation fadeOut = AnimationUtils.loadAnimation(YourActivity.this, R.anim.fade_out);
imageView.startAnimation(fadeOut);

fadeOut.setAnimationListener(new Animation.AnimationListener() {
      @Override
      public void onAnimationStart(Animation animation) {
      }
      @Override
      public void onAnimationEnd(Animation animation) {
          Animation fadeIn = AnimationUtils.loadAnimation(YourActivity.this, R.anim.fade_in);
          imageView.startAnimation(fadeIn);
      }
      @Override
      public void onAnimationRepeat(Animation animation) {
      }
});

For fade in animation , create new folder named 'anim' in your res folder and inside it, create 'fade_in.xml' with following code

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android" >

    <alpha
        android:duration="@android:integer/config_mediumAnimTime"
        android:fromAlpha="0.0"
        android:interpolator="@android:anim/decelerate_interpolator"
        android:toAlpha="1.0" />

</set>

now to run this animation on your imageview, use following code in your activity

Animation anim = AnimationUtils.loadAnimation(YourActivity.this, R.anim.fade_in);
imageView.setAnimation(anim);
anim.start();

for fadeout animation, just swap values of android:fromAlpha and android:toAlpha

Hope this helps.