UISlider 拇指在不接触拇指的情况下移动

Question

我在我的项目中使用 UISlider。通常，只要我们触摸并拖动拇指，拇指就会移动。但是，就我而言，当我触摸到它的边缘但没有触摸它时，拇指移动了。像这样：

这是我的代码：

self.slider = [[UISlider alloc] initWithFrame:CGRectMake(30, [UIScreen mainScreen].bounds.size.height - 200, [UIScreen mainScreen].bounds.size.width-30, 30)];
[self.view addSubview:self.slider];

为什么拇指动了，如何处理？我的目标是，拇指只有在我触摸并拖动它时才会移动，而当我触摸到它的边缘时它不会移动。

Answer 1

为此，您需要将 taoGesture 与 UISlider 一起使用，因此首先在您的滑块对象中添加 UITapGestureRecognizer，然后在 gestureRecognizer 选择器的操作方法中设置其值。

在视图中添加滑块后添加以下代码。

UITapGestureRecognizer *tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(onSliderTap:)];
[self.slider addGestureRecognizer:tapGestureRecognizer];

现在onSliderTap你可以获取定位点然后更新滑块的值

- (void)onSliderTap:(UITapGestureRecognizer *)recognizer {
    float width = self.slider.frame.size.width;
    CGPoint point = [recognizer locationInView:recognizer.view];
    CGFloat sliderX = self.slider.frame.origin.x;
    float newValue = ((point.x - sliderX) * self.slider.maximumValue) / width;
    [self.slider setValue:newValue];
}

Answer 2

尝试添加以下代码：

  - (void)viewDidLoad
 {

     UITapGestureRecognizer *tapGest = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(sliderTapped:)];
     [slider addGestureRecognizer:tapGest];

 }

 - (void)sliderTapped:(UIGestureRecognizer *)tapGest 
 {
        UISlider* slider = (UISlider*)tapGest.view;
        if (slider.highlighted)
            return; // tap on thumb, let slider deal with it
        CGPoint pt = [tapGest locationInView: slider];
        CGFloat percentage = pt.x / slider.bounds.size.width;
        CGFloat delta = percentage * (slider.maximumValue - slider.minimumValue);
        CGFloat value = slider.minimumValue + delta;
        [slider setValue:value animated:YES];

  }

UISlider 拇指在不接触拇指的情况下移动

UISlider thumb moving without touching thumb

objective-c

uislider

ios