Changes

The last area of iOS touch screen event handling that we will look at in this book involves the detection of gestures involving movement. As covered in a previous chapter, a gesture refers the activity that takes place in the time between a finger touching the screen and the finger then being lifted from the screen. In the chapter entitled [[An Example iOS 4 iPhone Touch, Multitouch and Tap Application Applications (Xcode 4)|An Example iOS 4 iPhone Touch, Multitouch and Tap ApplicationApplications]] we dealt with touches that did not involve any movement across the screen surface. We will now create an example that tracks the coordinates of a finger as it moves across the screen.