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copied!<p>Here is a simple custom gesture recognizers for double taps where you can specify the maximum allowed time between taps. This is based on @Walters answer.</p> <p>PbDoubleTapGestureRecognizer.h :</p> <pre><code>@interface PbDoubleTapGestureRecognizer : UIGestureRecognizer @property (nonatomic) NSTimeInterval maximumDoubleTapDuration; @end </code></pre> <p>PbDoubleTapGestureRecognizer.m :</p> <pre><code>#import "PbDoubleTapGestureRecognizer.h" #import <UIKit/UIGestureRecognizerSubclass.h> @interface PbDoubleTapGestureRecognizer () @property (nonatomic) int tapCount; @property (nonatomic) NSTimeInterval startTimestamp; @end @implementation PbDoubleTapGestureRecognizer - (id)initWithTarget:(id)target action:(SEL)action { self = [super initWithTarget:target action:action]; if (self) { _maximumDoubleTapDuration = 0.3f; // assign default value } return self; } -(void)dealloc { [NSObject cancelPreviousPerformRequestsWithTarget:self]; } - (void)reset { [super reset]; [NSObject cancelPreviousPerformRequestsWithTarget:self]; self.tapCount = 0; self.startTimestamp = 0.f; } - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { [super touchesBegan:touches withEvent:event]; if (touches.count != 1 ) { self.state = UIGestureRecognizerStateFailed; } else { if (self.tapCount == 0) { self.startTimestamp = event.timestamp; [self performSelector:@selector(timeoutMethod) withObject:self afterDelay:self.maximumDoubleTapDuration]; } self.tapCount++; } } - (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event { [super touchesMoved:touches withEvent:event]; } - (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event { [super touchesEnded:touches withEvent:event]; if (self.tapCount > 2) { self.state = UIGestureRecognizerStateFailed; } else if (self.tapCount == 2 && event.timestamp < self.startTimestamp + self.maximumDoubleTapDuration) { [NSObject cancelPreviousPerformRequestsWithTarget:self]; NSLog(@"Recognized in %f", event.timestamp - self.startTimestamp); self.state = UIGestureRecognizerStateRecognized; } } - (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event { [super touchesCancelled:touches withEvent:event]; self.state = UIGestureRecognizerStateFailed; } - (void)timeoutMethod { self.state = UIGestureRecognizerStateFailed; } @end </code></pre> <p>You can use it like this:</p> <pre><code>PbDoubleTapGestureRecognizer *doubleTapGr = [[PbDoubleTapGestureRecognizer alloc]initWithTarget:self action:@selector(_doubleTapAction)]; doubleTapGr.maximumDoubleTapDuration = 0.4; [yourView addGestureRecognizer:doubleTapGr]; </code></pre> <p>You can combine this with <code>requireGestureRecognizerToFail:</code> to get the behavior that was asked for.</p>

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