iOS如何自定义UISlider

添加下面代码就可以了

-(void)addMySlider{   
        //左右轨的图片 
        UIImage *stetchLeftTrack= [UIImage imageNamed:@"light_off_on.png"]; 
        UIImage *stetchRightTrack = [UIImage imageNamed:@"light_off_back.png"]; 
        //滑块图片 
        UIImage *thumbImage = [UIImage imageNamed:@"light_round.png"]; 
        UISlider *sliderA=[[UISlider alloc]initWithFrame:CGRectMake(30, 320, 257, 7)]; 
        sliderA.backgroundColor = [UIColor clearColor]; 
        sliderA.value=0.5; 
        sliderA.minimumValue=0.0; 
        sliderA.maximumValue=1.0; 
        [sliderA setMinimumTrackImage:stetchLeftTrack forState:UIControlStateNormal]; 
        [sliderA setMaximumTrackImage:stetchRightTrack forState:UIControlStateNormal]; 
        //注意这里要加UIControlStateHightlighted的状态，否则当拖动滑块时滑块将变成原生的控件 
        [sliderA setThumbImage:thumbImage forState:UIControlStateHighlighted]; 
        [sliderA setThumbImage:thumbImage forState:UIControlStateNormal]; 
        //滑块拖动时的事件 
        [sliderA addTarget:self action:@selector(sliderValueChanged) forControlEvents:UIControlEventValueChanged]; 
        //滑动拖动后的事件 
        [sliderA addTarget:self action:@selector(sliderDragUp) forControlEvents:UIControlEventTouchUpInside]; 
        [self.view addSubview:sliderA];   
    } 
    -(void)sliderDragUp{         
        NSLog(@"sliderDragUp"); 
    }     
    -(void)sliderValueChanged{        
        NSLog(@"sliderValueChanged");     
    }