A Complete Guide to Customizing Android Activity Transition Animations

Introduction

Android activities often use default transition animations when started or finished. However, developers may wish to customize these animations for better user experience. This article explores two primary methods to change the startActivity() and finish() transition animations, focusing on alpha fade effects.

Method 1: Using Animation and XML

This method involves defining fade animations in XML and applying them programmatically. It provides fine-grained control over the animation properties.

First, create fadein.xml for fade-in animation:

<set xmlns:android="http://schemas.android.com/apk/res/android" 
     android:fillAfter="true">
     <alpha android:fromAlpha="1.0" 
            android:toAlpha="0.0"
            android:duration="500"/> // Time in milliseconds
</set>

Similarly, fadeout.xml for fade-out:

<set xmlns:android="http://schemas.android.com/apk/res/android"
           android:fillAfter="true">
  <alpha android:fromAlpha="0.0"
         android:toAlpha="1.0"
         android:duration="500"/>
</set>

In the Activity class, implement methods to run these animations. For finishing an activity:

private void finishTask() {
    if(condition){
        finish();
        runFadeInAnimation();
    }
}

private void runFadeInAnimation() {
    Animation a = AnimationUtils.loadAnimation(this, R.anim.fadein);
    a.reset();
    LinearLayout ll = (LinearLayout) findViewById(R.id.yourviewhere);
    ll.clearAnimation();
    ll.startAnimation(a);   
}

In the new Activity, run fade-out animation in onCreate() to create a seamless transition.

Method 2: Using overridePendingTransition()

As an alternative, starting from API level 5, you can use overridePendingTransition() immediately after startActivity() or finish(). This method allows specifying explicit transition animations.

startActivity(intent);
overridePendingTransition(R.anim.hold, R.anim.fade_in);

finish();
overridePendingTransition(R.anim.hold, R.anim.fade_out);

This approach is simpler but may have limitations in complex scenarios.

Comparison and Recommendations

Method 1 offers more flexibility and control, suitable for custom animations. Method 2 is straightforward for basic transitions. Developers should choose based on their requirements and API compatibility.

Conclusion

Customizing Android activity transition animations enhances app aesthetics. By leveraging XML animations and programmatic control or using overridePendingTransition(), developers can implement smooth fade effects. Always test animations across devices to ensure consistency.