Android ontouchevent example. The ID for a pointer at a...

  • Android ontouchevent example. The ID for a pointer at a particular index in the list of current pointers Android: onTouchEvent for textView Asked 15 years, 4 months ago Modified 8 years, 10 months ago Viewed 13k times Learn Android - Responding to Touch Events Many custom views need to accept user interaction in the form of touch events. Do you see why every new call to onTouchEvent remakes them each time, and initializes them to zero? Instead, declare them as variables up at the top of your class definition. How do I register the activity as the ontouchEvent listener to the main content view. View. android. I need to do some action on single touch also. xml file and refer to the following code. onTouchEvent () ViewGroup. Keep track of pointers Use the pointer's index and ID to keep track of the individual pointers positions within a MotionEvent. A ScrollView intercepts MotionEvent to check if it should scroll the view before passing them to the child. There are numerous resources out there (articles and videos) that explain pretty thoroughly the mechanisms of Android’s touch event system… Here’s a quick example of how to get the length of time that a series of touch events has taken, again by editing onTouchEvent(): public boolean onTouchEvent(MotionEvent e) { Well organized and easy to understand Web building tutorials with lots of examples of how to use HTML, CSS, JavaScript, SQL, Python, PHP, Bootstrap, Java, XML and more. You can use GestureDetector and ScaleGestureDetector together when you want a view to recognize additional gestures. there is a setContentView () which takes a layout id. Android provides a variety of APIs to help you create and detect gestures. Handling click and touch events in Android Handling click and touch events in Android In Android, there are several ways to handle click and touch events. MotionEvent) in View. In the case where you just touch somewhere on the screen, nobody is interested in the event, so it flows all the way down to your code. In the View. This tutorial covers setting up the project, implementing GestureDetector, and handling different gestures. in my app, i want two things to happen. Note that select Kotlin as the programming language. The main ones are ACTION_DOWN: This is triggered once when your finger first touches the view. Do I override the parent's onTouchEvent or the child's onTouchEvent? Do I make an OnTouchListener and add the gesture detector there? The documentation shows an example for how to add a gesture detector to the activity itself but it is not clear how to add it to a view. The documentation also recommends overriding performClick() instead if you only intend to handle click gestures. */ ImageView itan2; @Override Handling multitouch in a surface public class CustomSurfaceView extends SurfaceView { @Override public boolean onTouchEvent(MotionEvent e) { super. Each pointer, in turn, is referenced by an index value and assigned an ID. After many experiments with onTouchEvent and onTouch, I found that onTouch works everywhere you want (whether it is in activity or view) as long as you have declared the interface and put the Liste The Android documentation recommends calling super. You can use GestureDetector in conjunction with the onTouchEvent() method described above. You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. This lesson describes how to track movement in touch events. For example, an event with ACTION_MOVE can indicate a movement for all pointers down at that moment. If I touch the container and I move the finger, I want to move the view to follow my finger. The onTouchEvent() are called down-top (from child to parent) until one of them consum it and the cycle finishs. action){ MotionEvent. For scaling, Android provides ScaleGestureDetector. Android Event Listeners If I swipe on a Button I want onInterceptTouchEvent to Intercept the call to the Button 's onTouchEvent and perform a swipe action. g. To provide quality support for touch-based user interfaces, touch events offer the ability to interpret finger (or stylus) activity on touch screens or trackpads. To create a new project in Android Studio please refer to How to Create/Start a New Project in Android Studio. Visual examples of how touch events flow through the Android view hierarchy. ) You can extend PointerInputScope with a function that takes three lambda parameters and routes the events to the intended one. As previously discussed 文章浏览阅读3. , the number of pointers, the X/Y coordinates and size and pressure of each pointer. How to override performClick in Kotlin to avoid warning? next. 37 I was struggling with adding a gesture detector to a subview in my project. This repository contains a sample application demonstrating many of the techniques for doing custom touch event handling discussed in "Mastering the Android Touch System". The index of a pointer is its position within this array. May 20, 2024 · In order to make your OpenGL ES application respond to touch events, you must implement the onTouchEvent() method in your GLSurfaceView class. Refer to the following related resources: Setup a touch listener In order to make your OpenGL ES application respond to touch events, you must implement the onTouchEvent() method in your GLSurfaceView class. view. onTouchEvent(MotionEvent) method ensure you call onTouchEvent(android. Handling Multiple Touches The chapter entitled An Android Event Handling Tutorial began exploring event handling within the narrow context of a single-touch event. onContextClick(MotionEvent) you must call onGenericMotionEvent(android. Handling standard events such as clicks, long clicks, key presses, etc are very basic and handled in other guides. i used OnTouchListener() for this and it works fine. Android framework places each If subclassing a view is not desired, then the same motion events can be tracked by adding an OnTouchListener to the view. You declared two floats (touchX and touchY) inside the onTouchEvent method. If listening for OnContextClickListener. OnTouchListener { view, motionEvent -> when (motionEvent. Android provides various ways to detect and respond to touch events, allowing developers to implement gestures like swiping, dragging, and pinching. If you need to write an Android onTouchEvent method inside a View class, here’s some example source code (boilerplate/skeleton code) that shows how to implement this method, including how to use the MotionEvent in the method, and how to get the x and y location of the touch event: Jul 23, 2025 · To check if there were touch movements in multiple views displayed on a screen in Android, we shall follow the following steps: Step 1: Create a New Project. OnTouchListener. The onInterceptTouchEvent() method Single and multi touch in Android. The event in this exmple are Action Down, Move and Action up. dispatchTouchEvent which will route the touch event to either OnTouchListener. In Android, the View class defines an overridable method named OnTouchEvent to process all the touch activity. All of us have already deal with android touch events with or without success! Gather data When a user places one or more fingers on the screen, this triggers the callback onTouchEvent() on the view that receives the touch events. setOnTouchListener(View. xml file Go to the activity_main. Android onTouch & GestureDetector for Dummies This article explains how to use GestureDetector in Android. I used the following code to detect the single finger touch and double finger touch. Build AI-powered Android apps with Gemini APIs and more. View. ACTION_DOWN and measure the time Explore the essentials of event handling in Android applications, including key concepts and practical examples to enhance user interaction. In an application when a button click event is detected, the Android framework will call the onClick () method of that particular view. Index: a MotionEvent stores pointer information in an array. As previously discussed, each touch in a multi-touch situation is considered by the Android framework to be a pointer. when i click the ImageButt In this article, I will elaborate on how touch events are dispatched and handled in the Android view tree. kt for the mapping to PointerEvent. Some of the gestures it supports include onDown(), onLongPress(), onFling(), and so on. This method returns true if the touch event has been handled by the view. Learn how to implement gesture recognition in Android apps with custom touch handling. Nov 11, 2025 · To react to touch events. In practice, most Android devices can respond to multiple consecutive touches (though it is important to note that the number of simultaneous touches that can be detected varies depending on the device). public class MprojectActivity extends Activity { /** Called when the activity is first created. The Android View also defines an event named Touch that allows an event handler to be attached to any View object. And if I simply click on a Button I do not want the onInterceptTouchEvent to be called. Although your app should not depend on touch gestures for basic behaviors (since… Follow this- 1 • 3 Android Tutorial for Beginners 2 • Playlist 3 • Playlist 4 • Playlist 5 • 4 Android Material Design Tutorial How to learn JAVA from slidenerd? Events represents a response to user's interaction with input controls, such as press of a button or touch of the screen. Overview Gesture recognition and handling touch events is an important part of developing user interactions. ACTION_MOVE: This is called every time your finger moves a little Learn how to build Android apps with advanced touch interactions using Kotlin. If I This class describes how to write apps that allow users to interact with an app via touch gestures. For each sequence of touch events—such as position, pressure, size, and addition of another finger—that is identified as a gesture, onTouchEvent() is fired several times. There are a number of actions you can filter out. when i touch and drag the ImageButton, it should move along with my finger. I'd like to do a simple control: a container with a view inside. onGenericMotionEvent(MotionEvent). The methods defined in your callback will be executed when the events occur. The MotionEvent class contains the touch related information, e. If onInterceptTouchEvent() returns true, the MotionEvent is intercepted, meaning it isn't passed onto the child but rather to the onTouchEvent() method of the parent. Select Kotlin as the programming language. Use touch to perform scaling As discussed in Detect common gestures, use GestureDetector to detect common gestures used by Android, such as scrolling, flinging, and touch and hold. you override the onTouchEvent() method. To make sure each view correctly receives the touch events intended for it, override the onInterceptTouchEvent() method. This guide is focused on handling other more specialized gestures such as: Swiping in For example, the simplest case is that of View. The code detects the double finger touch (when count==2). ACTION_DO Step 1: Create a New Project To create a new project in Android Studio, refer to How to Create/Start a New Project in Android Studio. ACTION_MOVE events and translate them to an angle of rotation for a shape. Learn the best practices for handling touch events in Android applications, including code examples and common pitfalls. The type of the touch activity is defined by enumeration members Down, PointerDown, Move, Up, and PointerUp. dispatchTouchEvent() is the first method in the activity and onTouchEvent() of activity is the last method of activity that receives touch events in the touch event flow. onClickListener event listener and implement the corresponding onClick () callback method. Your All-in-One Learning Portal: GeeksforGeeks is a comprehensive educational platform that empowers learners across domains-spanning computer science and programming, school education, upskilling, commerce, software tools, competitive exams, and more. Below is the code for the activity_main. onTouchEvent () But events only follow the chain until they are consumed (meaning somebody returns true from onTouchEvent() or a listener). The example implementation below shows how to listen for MotionEvent. You can get access to touch events by overriding onTouchEvent. onTouchEvent () Activity. onTouch if it's defined or to the extension method onTouchEvent. . For Example, if a button is to reply to a click event it must register to look at the . Feb 2, 2026 · Handling touch events in a ViewGroup takes special care because it's common for a ViewGroup to have children that are targets for different touch events than the ViewGroup itself. What kind of container (layout) shoul (See the Android platform implementation file PointerEvent. The current number of pointers can be obtained via a call to the getPointerCount () method of the current MotionEvent object. Master advanced touchscreen interactions for enhanced user experience. The article consists of 2 parts… I want to set the onTouchEvent for the view that covers the entire screen space of the activity. onTouchEvent() when overriding this in a custom view, since it does some state management. A new onTouchEvent() is triggered with an ACTION_MOVE event whenever the current touch contact position, pressure, or size changes. ACTION_DOWN, and a different long for a second motionEvent. 7k次。本文介绍了如何在Android应用中处理触摸屏事件，通过两种方法展示如何为视图设置触摸监听器，包括使用OnTouchListener接口和匿名内部类的方式，并解释了ACTION_DOWN、ACTION_UP等常见触摸事件。 In Android development, handling gestures, swipes, and touch events is a crucial aspect of creating interactive and responsive user interfaces. As described in Detect common gestures, all these events are recorded in the MotionEvent parameter of onTouchEvent(). onTouchEvent(e); if(e. I figure I would set a long for motionEvent. This tutorial describes how to use the touch API in Android applications. getPointerCount() > 2){ return false; // If we want to limit the amount of pointers, we return false // which disallows the pointer. I am trying to catch double-tap events using OnTouchListener. Intercept touch events in a View Group The onInterceptTouchEvent() method is called whenever a touch event is detected on the surface of a ViewGroup, including on the surface of its children. Detecting All Supported Gestures When you instantiate a GestureDetectorCompat object, one of the parameters it takes is a class that implements The following examples show how to use android. Learn how to override onTouchEvent for custom views in Android with step-by-step instructions and code examples. Here are some of the most common approaches: Using the OnClickListener interface: This is the most common way to handle click events in Android. Android Motion Event Detailed Explanation and Handling Views’ onTouchEvent What each action mask means, empty pointers array and few words about the JNI & native parts Hi there! In the Navigine … Gesture recognition and handling touch events is an important part of developing user interactions. 19 Here is a simple example on how to detect a simple on touch event, get coords and show a toast. Step 2: Working with the activity_main. xml file. MotionEvent). type. (example also taken from the documentation) I thought I could override the Activitys dispatchTouchEvent (MotionEvent ev) and call a custom touch event in my overlay, but this has the effect of not translating the input coords depending on the position of my view (for example all events will pass appear to be happening 20 or so px below the actual touch as the system bar is not taken into Android provides the GestureDetector class for detecting common gestures. This guide is focused on handling other more specialized gestures such as: Swiping in a direction Double tapping for zooming Pinch to zoom in or out Dragging and dropping I have an example which I collect from Internet. jlxb, hj39, 7y0xk, 9g27e, ah3y8, yx3l, yprg, ibpqz, sfvtdm, 3kzwf,