UIKit

Responder chain and hit testing

When you tap the screen in a UIKit app, how does the system decide which view receives the touch (hit testing)?

Your answer

Interviewer mode

See the short answer

Starting from UIWindow, hitTest(_:with:) recursively walks the subviews in reverse order, finds the deepest view whose point(inside:) returns true, and hands it the touch.

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Responder chain and hit testing

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