IOS Event Delivery and response process

IOS Event Delivery and response process

-->> Event Arrival-->> Event Distribution-->> Event response

Event (events)

Official documents (Events (IOS)) are described in this way:
Users manipulate their IOS devices in a number of ways, such as touching the screen or shaking the device. IOS interprets when and how a user was manipulating the hardware and passes this information to your app. The more your app responds to actions in natural and intuitive ways, the more compelling the experience are for the user.
1. Touch Events (single point of events, multi-touch and various gestures)
2. Rocking Time (Motion Events) (Gravity, acceleration and other sensors)
3. Remote Control Events (Remote-control events) (wire-controlled headphones, AirPlay, etc.)

Event Distribution (Delivery)

Touch events: Hardware Interrupts---UIKit packaged into Uievent objects-->uiapplication objects->key window->hit-testing V Iew
Other events: Key Window-> First Responder
Objective:
The ultimate goal of these event paths is to find a object that can handle and respond to an event. Therefore, UIKit first sends the event to the object that's best suited to handle the event. For touch events, this object is the Hit-test view, and for other events, this object is the first responder.
Method:
-Hit-testing Returns The View Where A touch occurred (touch)
The Hit-test view is given the first opportunity to handle a touch event. If The Hit-test view cannot handle an event, the event travels up, the view ' s chain of responders as described in "the Re Sponder Chain is made up of Responder Objects "until the system finds a object that can handle it.
-The Responder Chain is made up of Responder Objects (Motion Or r-c)

Incident response

Attention:
Hittest:withevent: The method will ignore the view (hidden = YES)
View that prohibits user action (userinteractionenabled = NO)
And a view with an alpha level less than 0.01 (Alpha < 0.01)
If the area of a child view exceeds the bound area of the parent view (the clips Tobounds property of the parent view is no, so that the contents of the view beyond the parent view's bound area will also be displayed), then the touch operations of the child view outside the parent view are not recognized by the parent view normally. Because the parent view's Pointinside:withevent: Method returns no, this does not continue to facilitate the sub-view downward. Of course, you can also override the Pointinside:withevent: method to handle this situation.

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IOS Event Delivery and response process