UITouch / UIEvent -推迟活动？

Question

有任何方法来延迟这个touchBegan函数的事件吗？

- (void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *followTouch = [[event allTouches] anyObject];

bull.center = [followTouch locationInView:followTouch.view];}

Answer 1

下面是一个例子。它在触觉移动后的半秒钟内使正方形的运动活跃起来：

-(void)pan:(UIPanGestureRecognizer *)pan {
    CGPoint touchLocation = [pan locationInView:self.view];
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, 0.5 * NSEC_PER_SEC), dispatch_get_main_queue(), ^{
        self.square.center = touchLocation;
    });
}

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    UIView *square = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 10, 10)];
    square.backgroundColor = [UIColor redColor];
    self.square = square;
    [self.view addSubview:square];
    UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(pan:)];
    [self.view addGestureRecognizer:pan];
}