Can I change the Android startActivity() transition animation?

Question

I am starting an activity and would rather have a alpha fade-in for startActivity(), and a fade-out for the finish(). How can I go about this in th

Answer 1

I wanted to use the styles.xml solution, but it did not work for me with activities. Turns out that instead of using android:windowEnterAnimation and android:windowExitAnimation, I need to use the activity animations like this:

Also, for some reason this only worked from Android 8 and above. I added the following code to my BaseActivity, to fix it for the API levels below:

override fun finish() {
    super.finish()
    setAnimationsFix()
}

/**
 * The activityCloseExitAnimation and activityCloseEnterAnimation properties do not work correctly when applied from the theme.
 * So in this fix, we retrieve them from the theme, and apply them.
 * @suppress Incorrect warning: https://stackoverflow.com/a/36263900/1395437
 */
@SuppressLint("ResourceType")
private fun setAnimationsFix() {
    // Retrieve the animations set in the theme applied to this activity in the manifest..
    var activityStyle = theme.obtainStyledAttributes(intArrayOf(attr.windowAnimationStyle))
    val windowAnimationStyleResId = activityStyle.getResourceId(0, 0)
    activityStyle.recycle()
    // Now retrieve the resource ids of the actual animations used in the animation style pointed to by
    // the window animation resource id.
    activityStyle = theme.obtainStyledAttributes(windowAnimationStyleResId, intArrayOf(activityCloseEnterAnimation, activityCloseExitAnimation))
    val activityCloseEnterAnimation = activityStyle.getResourceId(0, 0)
    val activityCloseExitAnimation = activityStyle.getResourceId(1, 0)
    activityStyle.recycle()
    overridePendingTransition(activityCloseEnterAnimation, activityCloseExitAnimation);
}