iOS - UILongPressGestureRecognizer [英] iOS - UILongPressGestureRecognizer

问题描述

在我的应用程序中，我希望 UILongPressGestureRecognizer 每秒发送一次连续的消息，直到按钮被释放.不幸的是，没有像连续"这样的状态，所以我需要使用开始"和结束"来控制我的消息.这是我到目前为止的代码，我在终端上获得了两个日志，但 while 循环没有停止?

In my app I want the UILongPressGestureRecognizer will send continuous messages every second until the button is released. Unfortunately there is no state like "continuous" so I need to use "began" and "ended" to control my messages. Here is my code I have so far, I get both logs on the terminal but the while loop is not stopping?

- (void)longPress:(UILongPressGestureRecognizer*)gesture {

    BOOL loop = NO;

    if (gesture.state == UIGestureRecognizerStateBegan) {
        NSLog(@"Long press detected.");
        loop = YES;
        while (loop){
            [[NSRunLoop currentRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceNow:1]];
            // here I want to do my stuff every second
        }
    } else if (gesture.state == UIGestureRecognizerStateEnded) {
        NSLog(@"Long press Ended");
        loop = NO;
    }
}

有人可以帮忙吗?

推荐答案

使用计时器(或可能隐藏计时器的 performSelector:withDelay:)是一个很好的建议，但是，大致:

Its a good suggestion to use a timer (or a performSelector:withDelay: which probably conceals a timer) but, roughly:

@property(strong,nonatomic) NSTimer *timer;

- (void)longPress:(UILongPressGestureRecognizer*)gesture {
    if (gesture.state == UIGestureRecognizerStateBegan) {
        NSLog(@"started");
        self.timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(stillPressing:) userInfo:nil repeats:YES];
    } else if (gesture.state == UIGestureRecognizerStateEnded) {
        [self.timer invalidate];
        self.timer = nil;
        NSLog(@"ended");
    }
}

- (void)stillPressing:(NSTimer *)timer {
    NSLog(@"still pressing");
}

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