关于从UISlider获取RGB颜色 的问题

改变UISLider的值使用方法：

@property (strong, nonatomic) IBOutlet UISlider *r;
@property (strong, nonatomic) IBOutlet UISlider *g;
@property (strong, nonatomic) IBOutlet UISlider *b;
@property (strong, nonatomic) IBOutlet UILabel *colorLabel;

- (void)viewDidLoad
{
    [super viewDidLoad];

    _r.minimumValue=0;
    _r.maximumValue=255;

    _g.minimumValue=0;
    _g.maximumValue=255;

    _b.minimumValue=0;
    _b.maximumValue=255;

    // Do any additional setup after loading the view, typically from a nib.
}

-(void)sliderValueChanged:(UISlider*)slider
{
    [_colorLabel setBackgroundColor:[UIColor colorWithRed:_r.value green:_g.value blue:_b.value alpha:1]];
}