我想在保持附加了UISlider
的UIButton
的同时连续更改UILongPressGestureRecognizer
的值。现在,我只能在上下触摸(开始/结束)时接到我的UILongPressGestureRecognizer
委托的电话。
是否可以在不占用UI的情况下执行从UIGestureRecognizerStateBegan
到UIGestureRecognizerStateEnded
的操作?不出所料,使用while()
循环不起作用。
最佳答案
这是一个工作示例,说明如何完成所需的工作。我测试了它,效果很好。
所有这些代码都放在* .m文件中。这是一个非常简单的类,仅扩展了UIViewController
。
#import "TSViewController.h"
@interface TSViewController ()
@property (nonatomic, strong) NSTimer *longPressTimer;
@end
@implementation TSViewController
- (void)viewDidLoad
{
[super viewDidLoad];
UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPressGesture:)];
[self.view addGestureRecognizer:longPress];
}
-(void)longPressGesture:(UILongPressGestureRecognizer*)longPress {
// The long press gesture recognizer has been, well, recognized
if (longPress.state == UIGestureRecognizerStateBegan) {
if (self.longPressTimer) {
[self.longPressTimer invalidate];
self.longPressTimer = nil;
}
// Here you can fine-tune how often the timer will be fired. Right
// now it's been fired every 0.5 seconds
self.longPressTimer = [NSTimer scheduledTimerWithTimeInterval:0.5 target:self selector:@selector(longPressTimer:) userInfo:nil repeats:YES];
}
// Since a long press gesture is continuous you have to detect when it has ended
// or when it has been cancelled
if (longPress.state == UIGestureRecognizerStateEnded || longPress.state == UIGestureRecognizerStateCancelled) {
[self.longPressTimer invalidate];
self.longPressTimer = nil;
}
}
-(void)longPressTimer:(NSTimer*)timer {
NSLog(@"User is long-pressing");
}
@end
希望这可以帮助!
关于iphone - 在UILongPressGestureRecognizer的持续时间内执行操作,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/19436996/