how to debug android studio ontouch android

HOW TO DEBUG ANDROID STUDIO ONTOUCH ANDROID HOW TO

įirst, we need to register a touch listener for the view we are intending to move on the screen. That was the basic setup - now let’s start the movement part.

HOW TO DEBUG ANDROID STUDIO ONTOUCH ANDROID HOW TO

Let’s see how to do this.įirst, create an XML with a view then inflate it in the Activity. These flags get reset by the framework once the gesture is ended or if a new is gesture started because the framework gives priority to parents to control touch events above children.Īs developers, at some point in time, we may need to move a view inside a layout. A child view can call requestDisallowIntercept() on the parent to block onInterceptTouchEvent() for the duration of the current gesture.

If there is a touch event that a child is handling and the gesture has changed to drag, then the parent using onInterceptTouchEvent() method halts the touch events on child and consumes by itself. In this case, the parent ViewGroup constantly keeps monitoring the touch events flow. The best example here is a ScrollView which contains children to interact. In other words, a containing layout can choose to steal the event from a touched view before the view even receives the event. This is because at any given point of time if the ViewGroup wants to take ownership of the current gesture by stopping the events flow, what the child view is consuming and start consuming by itself. ViewGroup has an additional method, onInterceptTouchEvent(), which constantly monitors all the touch events flowing through the ViewGroup to its child views. A pointer id remains valid until the pointer eventually goes up (indicated by ACTION_UP or ACTION_POINTER_UP) or when the gesture is canceled (indicated by ACTION_CANCEL). Each pointer has a unique id that is assigned when it first goes down (indicated by ACTION_DOWN or ACTION_UP). This cycle repeats several times during interaction. You will not receive any more points in it.Ī gesture is defined as being started with ACTION_DOWN and ending with ACTION_UP. This can be defined as the change that happens between the cycle ACTION_DOWN and ACTION_UP.ĪCTION_POINTER_DOWN: This is similar to ACTION_DOWN but it’s invoked while the secondary or additional object comes in contact with the screen in case of multi-touch support.ĪCTION_POINTER_UP: This is similar to ACTION_UP but is invoked when the secondary or additional object releases the contact with the screen in case of multi-touch support.ĪCTION_CANCEL: This event was triggered when initially one view is handling the touches while it’s being transferred to the other. When you take off your finger on the screen ACTION_UP, is triggered.ĪCTION_MOVE: This was the event that is invoked while the pointer is been dragging on the screen. When you put your finger on the screen ACTION_DOWN, is triggered.ĪCTION_UP: This is the point where the object or finger releases the contact with the screen. The Actions available areĪCTION_DOWN: This is the first point where the object or finger comes in contact with the screen.

Action types with their names suggest what they do.

How to debug android studio ontouch android