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Human–ComPuter InteraCtIon
looks for an object capable of handling the event (Figure6.15). Because
the hit-test view is also a responder object, an application may also take
advantage of the responder chain when handling touch events. e
responder chain consists of a series of next responders (each returned
by the nextResponder method) in the sequence. e response behavior
itself is implemented by the responder objects (i.e., the UI components
such as the window, button, slider, etc.).
6.5 Summary
In this chapter, we reviewed three examples of UI toolkits, namely,
those for Java3D, Android, and iOS. ere are certainly many other
UI toolk