UISlider拇指移动而不触碰拇指

Question

我在我的项目中使用UISlider。通常，只要我们触摸并拖动拇指，拇指应该移动。但是，在我的情况下，当我触摸它的边缘而没有触及它时，拇指移动了。就像这样：

这里是我的代码：

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]; 

为什么拇指移动以及如何应对的呢？我的目标是，拇指只有在我触摸并拖动它时才会移动，而当我触摸它的边缘时拇指不会移动。

Answer 1

为此，您需要使用taoGesture和UISlider，所以首先在滑块对象中添加UITapGestureRecognizer，然后在gestureRecognizer选择器的action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就可以得到该位置，然后点更新滑块

- (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

尝试的价值添加以下代码：

- (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]; 

    }