ios - UISlider 通过发送者和类访问

Question

滑动时调用此aciton:

-(IBAction) sliding:(id)sender{
    UISlider *temp = (UISlider *) sender;
    int value = (int)temp.value;
    val.text= [[NSString alloc]initWithFormat:@"%i",value ]; // val is the name oflabel   
}

但是当我这样做的时候:

-(IBAction) sliding:(id)sender{

        int value = (int)sender->value;// ERROR(no member named value) WHY ?
        val.text= [[NSString alloc]initWithFormat:@"%i",value ]; // val is the name of label   
    }

如何在不创建 UISlider 类实例的情况下获取 slider 的值

Answer 1

您必须创建 UISlider 的 IBOutlet 并从中获取值。

@property(nonatomic,weak) IBOutlet UISlider *slider;
-(IBAction) sliding:(id)sender
{
val.text= [[NSString alloc]initWithFormat:@"%i",self.slider.value];    
}