tests/InstrumentClusterRendererSample/res/anim/icon_switcher_out.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- Copyright (C) 2016 The Android Open Source Project

     Licensed under the Apache License, Version 2.0 (the "License");
     you may not use this file except in compliance with the License.
     You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

     Unless required by applicable law or agreed to in writing, software
     distributed under the License is distributed on an "AS IS" BASIS,
     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     See the License for the specific language governing permissions and
     limitations under the License.
-->

<set>
    <!-- We hide this image only when a new one if fully visible, otherwise we may
         be in the state when we have 2 images semi-transparent, and even combined together they
         will look like semi-transparent it looks ugly when we have something underneath, e.g.
         when phone is answered.
      -->
    <alpha xmlns:android="http://schemas.android.com/apk/res/android"
           android:interpolator="@android:interpolator/linear"
           android:fromAlpha="1.0"
           android:toAlpha="0"
           android:startOffset="@android:integer/config_longAnimTime"
           android:duration="@android:integer/config_longAnimTime"/>
</set>