Courtesy: GitHub

Android BasicMultitouch Sample

Sample demonstrates the use of MotionEvent properties to keep track of individual touches across multiple touch events.

Introduction

This is an example of keeping track of individual touches across multiple MotionEvents.

This sample uses a custom View (TouchDisplayView) that responds to touch events and draws a colored circle for each touch point. The view holds data related to a touch pointer, including its current position, pressure, and its past touch history.

The View draws graphics based on data associated with each touch event to a canvas. A large circle indicates the current position of a touch, while smaller trailing circles represent previous positions for that touch. The size of the large circle is scaled depending on the pressure of the user's touch.

Pre-requisites

  • Android SDK 26
  • Android Build Tools v26.0.1
  • Android Support Repository

Screenshots

Screenshot 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

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

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 2017 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.

compile "com.android.support:support-v4:26.1.0"

compile "com.android.support:gridlayout-v7:26.1.0"

compile "com.android.support:cardview-v7:26.1.0"

compile "com.android.support:appcompat-v7:26.1.0"

compileSdkVersion 26

minSdkVersion 8

targetSdkVersion 26

package com.example.android.basicmultitouch

versionCode 1

versionName 1.0

MainActivity

This is an example of keeping track of individual touches across multiple {@link android.view.MotionEvent}s.

This is illustrated by a View ({@link TouchDisplayView}) that responds to touch events and draws coloured circles for each pointer, stores the last positions of this pointer and draws them. This example shows the relationship between MotionEvent indices, pointer identifiers and actions. * @see android.view.MotionEvent