Я взял код Росса и добавил несколько вещей, которые мне помогли. В частности, этот код не будет реагировать на свайп, пока не остановится. Это также предотвращает изменение направления движения в двух направлениях.
#import <UIKit/UIKit.h>
#define kMinimumGestureLength 25
#define kMaximumVariance 5
typedef enum swipeDirection {
kSwipeNone,
kSwipeLeft,
kSwipeRight
} tSwipeDirection;
@interface SwipeableTextView : UITextView {
CGPoint gestureStartPoint;
tSwipeDirection swipeDirection;
}
@end
@implementation SwipeableTextView
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesBegan:touches withEvent:event];
swipeDirection = kSwipeNone;
UITouch *touch =[touches anyObject];
gestureStartPoint = [touch locationInView:self];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesMoved:touches withEvent:event];
UITouch *touch = [touches anyObject];
CGPoint currentPosition = [touch locationInView:self];
CGFloat deltaX = fabsf(gestureStartPoint.x - currentPosition.x);
CGFloat deltaY = fabsf(gestureStartPoint.y - currentPosition.y);
// Check if we already started a swipe in a particular direction
// Don't let the user reverse once they get going
if (deltaX >= kMinimumGestureLength && deltaY <= kMaximumVariance &&
swipeDirection == kSwipeNone) {
if (gestureStartPoint.x < currentPosition.x) {
swipeDirection = kSwipeRight;
}
else {
swipeDirection = kSwipeLeft;
}
}
}
-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
if (swipeDirection == kSwipeRight) {
NSLog(@"Swipe right");
}
else if (swipeDirection == kSwipeLeft) {
NSLog(@"Swipe left");
}
[super touchesEnded:touches withEvent:event];
}
@end