Question

I have a widget which starts an activity when it is clicked. I’d like to have some kind of fancy animation to display this activity, rather than the standard scroll-from-right of Android. I’m having problems setting it, though. This is what I have:

slide_top_to_bottom.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android" android:interpolator="@android:anim/accelerate_interpolator">
    <translate android:fromYDelta="-100%" android:toXDelta="0" android:duration="100" />
    <alpha android:fromAlpha="0.0" android:toAlpha="1.0" android:duration="50" />
</set>

…which is referenced in anim.xml

<?xml version="1.0" encoding="utf-8"?>
<layoutAnimation xmlns:android="http://schemas.android.com/apk/res/android"
        android:delay="50%"
        android:animation="@anim/slide_top_to_bottom" />

But then where do I reference it from? I’ve tried both the base element of the activity I want to slide in, and the activitiy’s entry in the manifest, both times with

android:layoutAnimation="@+anim/anim"

I might be doing this all wrong. Any help is much appreciated!

Answer 1

You can create a custom Theme with a reference to your own animation and apply it to your Activity in your manifest file.
I was successful in applying a custom animation for a floating window using the following style definition. You might be able to do something similar if you set the parent of your style to be “@android:style/Animation.Activity”

Look at the following files for further details on what you can override.

https://github.com/android/platform_frameworks_base/blob/master/core/res/res/values/styles.xml
https://github.com/android/platform_frameworks_base/blob/master/core/res/res/values/themes.xml

Here’s my a portion of my styles.xml and manifest.xml

styles.xml

<style name="MyTheme" parent="@android:style/Theme.Panel">
    <item name="android:windowNoTitle">true</item>
    <item name="android:backgroundDimEnabled">true</item>
    <item name="android:windowAnimationStyle">@style/MyAnimation.Window</item>
</style>

<!-- Animations --> 
<style name="MyAnimation" /> 

<!-- Animations for a non-full-screen window or activity. --> 
<style name="MyAnimation.Window" parent="@android:style/Animation.Dialog"> 
    <item name="android:windowEnterAnimation">@anim/grow_from_middle</item>
    <item name="android:windowExitAnimation">@anim/shrink_to_middle</item>
</style> 

Manifest.xml

    <activity
        android:name="com.me.activity.MyActivity"
        android:label="@string/display_name"
        android:theme="@style/MyTheme">
    </activity>