I've created a custom picker view type of control by subclassing UIView. I would like to be able to send a "UIControlEventValueChanged" control event from within this control, so that I can register for it in whichever view controller is using the control.
How can I can I get my custom control to trigger this event when I deem it should be triggered?
Assuming your custom control extends UIControl, then you simply do:
[self sendActionsForControlEvents:UIControlEventValueChanged];
This will call all registered targets (via addTarget:action:forControlEvents: that this event has happened.
来源：https://stackoverflow.com/questions/17385614/how-can-i-send-a-uicontroleventvaluechanged-event-from-my-custom-control