![]() The event’s type is provided by MotionEvent.getActionMasked(). Some of the information you’ll use for multi-touch events includes the event’s type, pointer id, pointer index and coordinates. When dealing with multi-touch gestures, you may have more than a single pointer touching a View, the system provides information about each of the pointers and tracks them during a gesture, from the moment the first pointer touches the View until the last pointer is lifted off the View. Work of art 1 Tracking Multi-Touch Gestures The drawing follows the user’s finger (pointer). The following sample tracks single touch events on a View and allows the user to draw on it. The coordinates are decimals when the device has sub-pixel precision, and are otherwise integers.Ī set of consecutive events between ACTION_DOWN and ACTION_UP represent a gesture, for example, a scroll gesture starts with the user’s finger touching the screen ( ACTION_DOWN), it then moves up the screen ( ACTION_MOVE), before finally stopping and being lifted off the screen ( ACTION_UP). ![]() The coordinates are relative to the View and not the whole screen, meaning that a touch event at the upper left corner of the View will have the coordinates (0, 0). The event’s coordinates are represented by a pair of x and y coordinates where the touch event occurred. It returns an integer whose value can be one of the following: ACTION_DOWN, ACTION_UP, ACTION_MOVE and ACTION_CANCEL, which signal that a new touch gesture has started, finished, moved or been cancelled respectively. The event’s type is available through MotionEvent.getAction(). When dealing with single touch gestures, handle each event using its type and coordinates. To track touch events occurring on a View, set its OnTouchListener. #Android multitouch android#When the Android device’s screen supports multi-touch, the system can track and report information about all the pointers as they interact with the View. ![]() Therefor, a touch event may be the result of 1 or multiple pointers. The term “pointer” is used to refer to the finger or object (e.g. This allows you to track the user’s touch interactions with the View, and potentially detect gestures. Touch gesturesĪs a user touches a View, the system sends signals to the View with information about each touch event, including its nature and where exactly it occurred. Along the way, you’ll see how these concepts are used to build a simple drawing app. This article goes through the basics of touch gestures in Android, including single touch gestures, multi-touch gestures and some out-of-the-box common gestures Android supports. Following motion guidelines and supporting common touch gestures goes a long way toward providing an intuitive experience to your users. Pointers.press(in.pX, in.pY) įor(int p = 0 p - ( users interact with apps in many ways, a major one is through touch. Private static final int MAX_POINTERS = 10 Maybe a new set of eyes can help me tell what's wrong? Thanks for any help! Because it is a pipeline system, I have the events encapsulated in the InputObject which is somewhat similar to Robert Greene's. ![]() #Android multitouch code#Here's my current code in my thread which receives the input events from Android. Is this just an issue with how I am reacting to the events? Should I handle POINTER_DOWN and DOWN separately? Or should I detect which pointers are moving after the "UP" action to see which ones really are down despite what Android says? I had a single touch movement system before and none of these problems happened. When the pointer comes down on the area (which right now is just simply the lower left region), Android will send multiple "UP" and "DOWN" actions even though the pointer remains down the whole time. This also happens with button presses like the shooting button. Because my code believes the pointer is up, the game doesn't respond to it. When recording the pointer actions in LogCat, oftentimes Android will send an "UP" action when the pointer remains down, or just before a number of "MOVE" actions by the pointer. This seems like it should work well in practice, but in game it behaves very erratic. Each pointer's state is kept in a Pointer class, which is just a simple encapsulation of whether it is down, and it's coordinates. ![]() Right now, the code has a simple system that records which pointer ID is currently doing which action (right now just shooting and moving). It makes use of Robert Greene's Input Pipeline, modified for use with multitouch. After a lot of tinkering, I think I've finally come up with a good multitouch handling system for my android game. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |