xref: /developers/build/prebuilts/gradle/ElevationBasic

Android ElevationBasic Sample
===================================

This sample demonstrates ways to move a view in the z-axis using
`setTranslationZ()`. This method was introduced in API Level 21 ('Lollipop').

Introduction
------------

This sample uses two shapes, a circle and a square, and it demonstrates two
alternative ways to move a view in the z-axis. The first shape, the circle,
has a fixed elevation, which is defined in XML. The second view, the square,
changes its elevation using [setTranslationZ()][1] when a user touches it:

    shape2.setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View view, MotionEvent motionEvent) {
            int action = motionEvent.getActionMasked();
            /* Raise view on ACTION_DOWN and lower it on ACTION_UP. */
            switch (action) {
                case MotionEvent.ACTION_DOWN:
                    Log.d(TAG, "ACTION_DOWN on view.");
                    view.setTranslationZ(120);
                    break;
                case MotionEvent.ACTION_UP:
                    Log.d(TAG, "ACTION_UP on view.");
                    view.setTranslationZ(0);
                    break;
                default:
                    return false;
            }
            return true;
        }
    });

The elevation reverts back once the touch is removed.

[1]: https://developer.android.com/training/material/shadows-clipping.html#Elevation

Pre-requisites
--------------

- Android SDK v21
- Android Build Tools v21.1.1
- Android Support Repository

Screenshots
-------------

<img src="screenshots/fixed.png" height="400" alt="Screenshot"/> <img src="screenshots/raised.png" height="400" alt="Screenshot"/> 

Getting Started
---------------

This sample uses the Gradle build system. To build this project, use the
"gradlew build" command or use "Import Project" in Android Studio.

Support
-------

- Google+ Community: https://plus.google.com/communities/105153134372062985968
- Stack Overflow: http://stackoverflow.com/questions/tagged/android

If you've found an error in this sample, please file an issue:
https://github.com/googlesamples/android-ElevationBasic

Patches are encouraged, and may be submitted by forking this project and
submitting a pull request through GitHub. Please see CONTRIBUTING.md for more details.

License
-------

Copyright 2014 The Android Open Source Project, Inc.

Licensed to the Apache Software Foundation (ASF) under one or more contributor
license agreements.  See the NOTICE file distributed with this work for
additional information regarding copyright ownership.  The ASF licenses this
file to you 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.