Detecting Taps with UITapGestureRecognizer
The first UIGestureRecognizer subclass you will use is UITapGestureRecognizer. When the user taps a line in TouchTracker, you will present a menu that allows them to delete it. Open TouchTracker.xcodeproj from Chapter 19.
In the first part of this section, we are going to recognize a tap, determine which line is close to where the tap occurred, store a reference to that line, and change that line’s color to green so that the user knows it has been selected.
In TouchDrawView.m, edit the initWithFrame: method to create an instance of UITapGestureRecognizer and attach it to the TouchDrawView being initialized.
- (id)initWithFrame:(CGRect)r { self = [super ...Get iOS Programming: The Big Nerd Ranch Guide now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
