The "iOS Dev-88" event delivery principle explains which control handles events and how the responder chain is introduced

First, the touch event transfer principle

(1) The large direction is: passed from the parent control to the child control.

--The parent control checks whether it can accept event handling first

--and then look at the touch that's not in your own range

--if so, iterate over the child controls. See if there are any suitable child controls to handle

--assuming that the child controls are not appropriate, then the parent control will handle it on its own.

Another big rule is that events are usually from uiapplication >>> UIWindow >>> Individual controls

Second, the responder chain

--After finding this control, see if this control has implemented touches began, moved, and ended events.

--assuming no, then it will look for its parent control, which in turn pushes up.

--assuming that the control implements the method and also uses [super ...], then both the parent control and it can make the processing. So, be able to use [super ...] Enables multiple controls to handle the same event .

Note: special cases. Assuming that the current view is the view of the controller, then the previous responder of the view is the controller.

The "iOS Dev-88" event delivery principle explains which control handles events and how the responder chain is introduced