SlideTouchHandler slide with 2-finger

Question

At my project use 2-finger SlideTouchHandler control a list slide.

At the 2-finger slide processing, i find a problem when finger_A (2-finger: finger_A and finger_B) at the slide processing release and then press and slide agian. 

But at the continue slide processing，the list can't follow SlideTouchHandler's slide.

I add some log function at the List and SlideTouchHandler slot function. 

At the normal slide processing:

     SlideTouchHandler onStart and onSlide function log information output normal

     List onLoadItem function log output normal

But at the countinue slide process "when finger_A (2-finger: finger_A and finger_B) at the slide processing release and then press and slide agian":

     SlideTouchHandler onStart and onSlide function don't output log information

     List onLoadItem function don't output log information

Base the log output different， i add log output function at  SlideTouchHandler onEnd  function. The onEnd log output when fingerA release.

So when fingerA release, SlideTouchHandler think the 2-finger-slide processing is end.

If i want the SlideTouchHandler continue control the list slide after The Countinue_Slide_Processing, How can i achieve this function？

Answer 1

Hello,

So when fingerA release, SlideTouchHandler think the 2-finger-slide processing is end.

a 2 finger gesture starts when the user touches the screen with 2 fingers simultaneously (some small delay is accepted). When the user presses the fingers slowly one after another, it is not considered as a 2 finger gesture but as two separate 1 finger touches. When after recognizing a 2 finger gesture the user releases one of the fingers, the gesture ends.

Since in your application case the user releases one finger and after delay touches the screen again, it is considered as a separate one finger gesture. It will not be detected as a 2 finger gesture. To handle such special gesture you will need to react to the touch events individually and track them in a kind of state machine. It means you will need to implement you own touch handler.

Best regards

Paul Banach