Question

我有一个显示数字的标签。用户可以使用两个按钮递增或递减该标签的值。但是，如果用户持有任一按钮，则值将更快或更快地递增或递减。例如，保持1秒快1倍，2秒快2倍，3秒快3倍，依此类推。

这是我尝试但不起作用的原因，因为它不会继续调用该方法，并且您无法看到您在按钮上分配多个UILongGessureRecognizer。我需要另一种方法。有什么想法吗？

在我的viewDidLoad

中

    longPressGesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(incrementTwoX)];
    longerPressGesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(incrementThreeX)];
    [longPressGesture setMinimumPressDuration:1.5];
    [longPressGesture setMinimumPressDuration:3];
    //add long and longer press gestures to ALL buttons
    [weightLeftButton addGestureRecognizer:longPressGesture];
    [weightLeftButton addGestureRecognizer:longerPressGesture];
    [weightRightButton addGestureRecognizer:longPressGesture];
    [weightRightButton addGestureRecognizer:longerPressGesture];

-(void)incrementTwoX{
    NSLog(@"Holding");// doesn't get called Im guessing because you can't assign more then one long gesture recognizer to a button

}
-(void)incrementThreeX{
    NSLog(@"Holding Longer");

}
- (IBAction)weightRight:(id)sender {
    if([weightLabel.text  isEqual: @"Not Specified"]) weightLabel.text = 0;
    double value = [weightLabel.text doubleValue] + 0.1;
    weightLabel.text = [NSString stringWithFormat:@"%f", value];
}

我的进步..

第一次单击按钮并按住时，发生了什么？它只会将标签从未指定更改为0（零）。下次我点击并按住它完美地工作。然后在任何时候它只在每次点击时增加2并且不再保持。你能看出可能出现什么问题吗？使用2个增量来指定更多。点击并按住，无论你持有多长时间，你都不会看到标签的变化。然后，当您松开按钮时（在任何持续时间之后，即使是快速点击），您也会看到标签增量为2

- (void) increment:(UIButton*)currentButton label:(UILabel*)currentLabel{

    currentLabel.text = [NSString stringWithFormat: @"%d", _counter++];

    // if the button is still pressed, increment again in a little while:
    if ( currentButton.state != UIControlStateNormal ){
        NSLog(@"incrementing %d", _counter);
        CGFloat delay = 1.0/(CGFloat)_counter;

        dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)( delay * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{

            [self increment:currentButton label:currentLabel];
        });
    }
}

- (IBAction)weightRight:(id)sender {
    [self increment:weightRightButton label:weightLabel];
}

这就是病日志。第一次点击后，看看它是如何增加的。我放开了91.然后它只增加2，即使if语句只被调用一次。如果我持续很长时间或者只是做一些快速点击，那么看一下后续日志的时间增加2并不重要。发生了什么事？

2014-04-05 11:40:37.960 Stream Craft[1090:60b] incrementing 1
2014-04-05 11:40:38.961 Stream Craft[1090:60b] incrementing 2
2014-04-05 11:40:39.463 Stream Craft[1090:60b] incrementing 3
2014-04-05 11:40:39.798 Stream Craft[1090:60b] incrementing 4
2014-04-05 11:40:40.049 Stream Craft[1090:60b] incrementing 5
2014-04-05 11:40:40.250 Stream Craft[1090:60b] incrementing 6
2014-04-05 11:40:40.419 Stream Craft[1090:60b] incrementing 7
2014-04-05 11:40:40.563 Stream Craft[1090:60b] incrementing 8
2014-04-05 11:40:40.690 Stream Craft[1090:60b] incrementing 9
2014-04-05 11:40:40.803 Stream Craft[1090:60b] incrementing 10
2014-04-05 11:40:40.904 Stream Craft[1090:60b] incrementing 11
2014-04-05 11:40:40.997 Stream Craft[1090:60b] incrementing 12
2014-04-05 11:40:41.081 Stream Craft[1090:60b] incrementing 13
2014-04-05 11:40:41.160 Stream Craft[1090:60b] incrementing 14
2014-04-05 11:40:41.233 Stream Craft[1090:60b] incrementing 15
2014-04-05 11:40:41.301 Stream Craft[1090:60b] incrementing 16
2014-04-05 11:40:41.365 Stream Craft[1090:60b] incrementing 17
2014-04-05 11:40:41.425 Stream Craft[1090:60b] incrementing 18
2014-04-05 11:40:41.481 Stream Craft[1090:60b] incrementing 19
2014-04-05 11:40:41.535 Stream Craft[1090:60b] incrementing 20
2014-04-05 11:40:41.586 Stream Craft[1090:60b] incrementing 21
2014-04-05 11:40:41.636 Stream Craft[1090:60b] incrementing 22
2014-04-05 11:40:41.683 Stream Craft[1090:60b] incrementing 23
2014-04-05 11:40:41.728 Stream Craft[1090:60b] incrementing 24
2014-04-05 11:40:41.771 Stream Craft[1090:60b] incrementing 25
2014-04-05 11:40:41.813 Stream Craft[1090:60b] incrementing 26
2014-04-05 11:40:41.853 Stream Craft[1090:60b] incrementing 27
2014-04-05 11:40:41.891 Stream Craft[1090:60b] incrementing 28
2014-04-05 11:40:41.929 Stream Craft[1090:60b] incrementing 29
2014-04-05 11:40:41.964 Stream Craft[1090:60b] incrementing 30
2014-04-05 11:40:41.999 Stream Craft[1090:60b] incrementing 31
2014-04-05 11:40:42.033 Stream Craft[1090:60b] incrementing 32
2014-04-05 11:40:42.066 Stream Craft[1090:60b] incrementing 33
2014-04-05 11:40:42.097 Stream Craft[1090:60b] incrementing 34
2014-04-05 11:40:42.128 Stream Craft[1090:60b] incrementing 35
2014-04-05 11:40:42.158 Stream Craft[1090:60b] incrementing 36
2014-04-05 11:40:42.187 Stream Craft[1090:60b] incrementing 37
2014-04-05 11:40:42.216 Stream Craft[1090:60b] incrementing 38
2014-04-05 11:40:42.244 Stream Craft[1090:60b] incrementing 39
2014-04-05 11:40:42.271 Stream Craft[1090:60b] incrementing 40
2014-04-05 11:40:42.297 Stream Craft[1090:60b] incrementing 41
2014-04-05 11:40:42.323 Stream Craft[1090:60b] incrementing 42
2014-04-05 11:40:42.348 Stream Craft[1090:60b] incrementing 43
2014-04-05 11:40:42.373 Stream Craft[1090:60b] incrementing 44
2014-04-05 11:40:42.398 Stream Craft[1090:60b] incrementing 45
2014-04-05 11:40:42.420 Stream Craft[1090:60b] incrementing 46
2014-04-05 11:40:42.443 Stream Craft[1090:60b] incrementing 47
2014-04-05 11:40:42.466 Stream Craft[1090:60b] incrementing 48
2014-04-05 11:40:42.489 Stream Craft[1090:60b] incrementing 49
2014-04-05 11:40:42.510 Stream Craft[1090:60b] incrementing 50
2014-04-05 11:40:42.532 Stream Craft[1090:60b] incrementing 51
2014-04-05 11:40:42.553 Stream Craft[1090:60b] incrementing 52
2014-04-05 11:40:42.574 Stream Craft[1090:60b] incrementing 53
2014-04-05 11:40:42.593 Stream Craft[1090:60b] incrementing 54
2014-04-05 11:40:42.613 Stream Craft[1090:60b] incrementing 55
2014-04-05 11:40:42.632 Stream Craft[1090:60b] incrementing 56
2014-04-05 11:40:42.652 Stream Craft[1090:60b] incrementing 57
2014-04-05 11:40:42.671 Stream Craft[1090:60b] incrementing 58
2014-04-05 11:40:42.690 Stream Craft[1090:60b] incrementing 59
2014-04-05 11:40:42.708 Stream Craft[1090:60b] incrementing 60
2014-04-05 11:40:42.725 Stream Craft[1090:60b] incrementing 61
2014-04-05 11:40:42.743 Stream Craft[1090:60b] incrementing 62
2014-04-05 11:40:42.761 Stream Craft[1090:60b] incrementing 63
2014-04-05 11:40:42.777 Stream Craft[1090:60b] incrementing 64
2014-04-05 11:40:42.794 Stream Craft[1090:60b] incrementing 65
2014-04-05 11:40:42.811 Stream Craft[1090:60b] incrementing 66
2014-04-05 11:40:42.827 Stream Craft[1090:60b] incrementing 67
2014-04-05 11:40:42.843 Stream Craft[1090:60b] incrementing 68
2014-04-05 11:40:42.859 Stream Craft[1090:60b] incrementing 69
2014-04-05 11:40:42.875 Stream Craft[1090:60b] incrementing 70
2014-04-05 11:40:42.891 Stream Craft[1090:60b] incrementing 71
2014-04-05 11:40:42.907 Stream Craft[1090:60b] incrementing 72
2014-04-05 11:40:42.922 Stream Craft[1090:60b] incrementing 73
2014-04-05 11:40:42.938 Stream Craft[1090:60b] incrementing 74
2014-04-05 11:40:42.953 Stream Craft[1090:60b] incrementing 75
2014-04-05 11:40:42.968 Stream Craft[1090:60b] incrementing 76
2014-04-05 11:40:42.982 Stream Craft[1090:60b] incrementing 77
2014-04-05 11:40:42.996 Stream Craft[1090:60b] incrementing 78
2014-04-05 11:40:43.009 Stream Craft[1090:60b] incrementing 79
2014-04-05 11:40:43.023 Stream Craft[1090:60b] incrementing 80
2014-04-05 11:40:43.037 Stream Craft[1090:60b] incrementing 81
2014-04-05 11:40:43.051 Stream Craft[1090:60b] incrementing 82
2014-04-05 11:40:43.064 Stream Craft[1090:60b] incrementing 83
2014-04-05 11:40:43.077 Stream Craft[1090:60b] incrementing 84
2014-04-05 11:40:43.090 Stream Craft[1090:60b] incrementing 85
2014-04-05 11:40:43.103 Stream Craft[1090:60b] incrementing 86
2014-04-05 11:40:43.116 Stream Craft[1090:60b] incrementing 87
2014-04-05 11:40:43.119 Stream Craft[1090:60b] incrementing 88
2014-04-05 11:40:47.107 Stream Craft[1090:60b] incrementing 91
2014-04-05 11:40:52.233 Stream Craft[1090:60b] incrementing 93
2014-04-05 11:40:55.157 Stream Craft[1090:60b] Ad did load
2014-04-05 11:40:56.271 Stream Craft[1090:60b] incrementing 95
2014-04-05 11:41:00.233 Stream Craft[1090:60b] incrementing 97
2014-04-05 11:41:03.849 Stream Craft[1090:60b] incrementing 99
2014-04-05 11:41:10.193 Stream Craft[1090:60b] incrementing 101
2014-04-05 11:41:11.319 Stream Craft[1090:60b] incrementing 103
2014-04-05 11:41:12.122 Stream Craft[1090:60b] incrementing 105
2014-04-05 11:41:12.373 Stream Craft[1090:60b] incrementing 107
2014-04-05 11:41:12.544 Stream Craft[1090:60b] incrementing 109
2014-04-05 11:41:12.700 Stream Craft[1090:60b] incrementing 111
2014-04-05 11:41:12.802 Stream Craft[1090:60b] incrementing 113

这也是我的按钮和标签的设置方式......

@property (strong, nonatomic) IBOutlet UILabel *weightLabel;
@property (strong, nonatomic) IBOutlet UIButton *weightRightButton;
@property (strong, nonatomic) IBOutlet UIButton *weightLeftButton;

如果重要的话，发送的事件也是“触摸内部”我的按钮？

Answer 1

编辑更新了稍微好一点的例子。

如果你已经有了UIButton，我就不会弄乱手势识别器了。您需要做的就是不断检查按钮是否仍然按下，以及是否增加了计数器。您可以减少检查之间的时间，以便计数器速度从慢到快，如您所述。

这里的技巧是使用GCD通过dispatch_after（）在延迟后派遣一些工作。

这是一个完整的解决方案。如果您需要自定义加速时间（正如您在问题中讨论的那样），只需记录按钮首次按下的时间，并根据经过的总时间计算下一个增量的时间。

@interface TSViewController ()
{
    IBOutlet UILabel*   _label;

    IBOutlet UIButton*  _button;

    int                 _counter;

    NSDate*             _start;
}
@end

@implementation TSViewController

- (void) increment
{
    // if the button is still pressed, increment again in a little while:
    if ( _button.state != UIControlStateNormal )
    {
        _label.text = [NSString stringWithFormat: @"%d", _counter++];

        CGFloat elapsed = MAX(1, fabs( [_start timeIntervalSinceNow] ) );

        CGFloat delay = 0.9/elapsed;

        NSLog( @"%.3lf, delay: %.3lf", elapsed , delay);

        dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)( delay * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{

            [self increment];
        });
    }
}

- (IBAction) touchDown:(UIButton*)sender
{
    _start = [NSDate date];

    [self increment];
}

@end

Answer 2

首先，无需初始化UILongPressGestureRecognizer两次，您可以尝试以下方法： -

当您第一次在UILongPressGestureRecognizer的选择器中接听电话时方法，保存当前时间戳。
当您接到第二次/第三次呼叫时，保存当前时间戳后将其与第一次保存的时间戳进行比较。
现在将该值乘以时间戳的差值。

通过这种方式，您可以继续提高增值/减量的速度。

Answer 3

尝试使用UIStepper控件。

将此功能连接到其ValueChanged事件：

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    // `nameLabel` defined in .h file
    nameLabel = [[UILabel alloc] initWithFrame:CGRectMake(8.0f, 100.0f, 135.0f, 36.0f)];
    nameLabel.textColor = [UIColor whiteColor];
    [self.view addSubview:nameLabel];
}

-(IBAction)valChanged:(UIStepper *)sender
{
    [nameLabel setText:[NSString stringWithFormat:@"%0.1f", ((UIStepper *)sender).value]];
}

实施此代码并按住此步进器+几秒钟。

使用更长的UIButton保持持续时间更快的增量

3 个答案: