Android Multi-Touch

Multi-Touch

1. Multi-touch literally means that you use a finger that is greater than or equal to 2 to touch the phone screen.

The listening touch event in Android is the Ontouchevent method, its parameters are motionevent, and the following are some common methods of motionevent:

Getpointercount () Gets the number of points in the touch screen.

Getpointerid (int pointerindex) returns the indication of a touch point, PointIndex is the index of the first few touch points

GetX () gets the x-coordinate value of the touch screen

GetY () Gets the y-coordinate value of the touch screen

Getaction () Get touch screen action

Action_down: Start by pressing the action, such as pressing the screen with your finger.

ACTION_UP: Press the action to complete, such as the finger stops pressing the screen, leaving the screen.

Action_move: The movement between the beginning and completion of an action, such as a finger sliding on the screen.

Motionevent.action_pointer_1_down: First touch Point Click event

Motionevent.action_pointer_2_down: Second touch point Click event

MOTIONEVENT.ACTION_POINTER_1_UP: First touch Point release event

MOTIONEVENT.ACTION_POINTER_2_UP: Second touch point release event

2. An example is given below to illustrate:
Note: Ontouchevent returns true if it is not an effect

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Android Multi-Touch