突出显示时更改UIButton的背景颜色

Question

嗨我想更改用户点击按钮上的UIButton背景颜色。

我使用渐变显示背景颜色，当用户点击我需要更改渐变颜色。

[btn setTitle: @"Next" forState:UIControlStateNormal]; 
CAGradientLayer *gradient = [CAGradientLayer layer];    
gradient.frame = btn.bounds; 
gradient.cornerRadius = 10.0f; 
locations = [[NSArray alloc] initWithObjects: 0.0f, 0.0f, 0.0f,0.0f, nil]; 
[gradient setLocations:locations]; 
colorNext = [[NSArray alloc] initWithObjects:…., nil]; 
gradient.colors = colorNext; 
[locations release]; 
[btn.layer insertSublayer:gradient atIndex:0]; 
btn.titleLabel.textColor = [UIColor blackColor]; 

Answer 1

不推荐更改UIButton的内部层次结构，因为它可能会在未来的iOS更新中破坏。另外，它可能会导致Apple拒绝您的应用程序。更好的解决方案是创建一个按钮子类。这里是如何做到这一点的例子：

@interface MyButton : UIButton 
@end 

@implementation MyButton 

- (id)initWithFrame:(CGRect)frame 
{ 
    if (self = [super initWithFrame:frame]) 
    { 
     [self addObserver:self forKeyPath:@"highlighted" options:NSKeyValueObservingOptionNew context:NULL]; 
    } 

    return self; 
} 

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context 
{ 
    [self setNeedsDisplay]; 
} 

- (void)drawRect:(CGRect)rect 
{ 
    [super drawRect:rect]; 

    if (self.highlighted == YES) 
    { 
     CGContextRef ctx = UIGraphicsGetCurrentContext(); 

     CGColorSpaceRef rgb = CGColorSpaceCreateDeviceRGB(); 

     const CGFloat *topGradientColorComponents = CGColorGetComponents([UIColor whiteColor].CGColor); 
     const CGFloat *bottomGradientColorComponents = CGColorGetComponents([UIColor blackColor].CGColor); 

     CGFloat colors[] = 
     { 
      topGradientColorComponents[0], topGradientColorComponents[1], topGradientColorComponents[2], topGradientColorComponents[3], 
      bottomGradientColorComponents[0], bottomGradientColorComponents[1], bottomGradientColorComponents[2], bottomGradientColorComponents[3] 
     }; 
     CGGradientRef gradient = CGGradientCreateWithColorComponents(rgb, colors, NULL, sizeof(colors)/(sizeof(colors[0]) * 4)); 
     CGColorSpaceRelease(rgb); 

     CGContextDrawLinearGradient(ctx, gradient, CGPointMake(0, 0), CGPointMake(0, self.bounds.size.height), 0); 
     CGGradientRelease(gradient); 
    } 
    else 
    { 
     // Do custom drawing for normal state 
    } 
} 

- (void)dealloc 
{ 
    [self removeObserver:self forKeyPath:@"highlighted"]; 

    [super dealloc]; 
} 

@end 

您可能需要稍作修改，以得到它做你想要什么，但我想你的基本理念。

Answer 2

我发现这个AYUIButton在GitHub上和它完美的作品:) 下面是示例代码：

[btn setBackgroundColor:[UIColor redColor] forState:UIControlStateNormal]; 
[btn setBackgroundColor:[UIColor blueColor] forState:UIControlStateHighlighted]; 

Answer 3

试试这个：

[Button addTarget:self action:@selector(doSomething:) forControlEvents:UIControlEventTouchUpInside]; 
[Button addTarget:self action:@selector(setBgColorForButton:) forControlEvents:UIControlEventTouchDown]; 
[Button addTarget:self action:@selector(clearBgColorForButton:) forControlEvents:UIControlEventTouchDragExit]; 

-(void)setBgColorForButton:(UIButton*)sender 
{ 
    [sender setBackgroundColor:[UIColor blackColor]]; 
} 

-(void)clearBgColorForButton:(UIButton*)sender 
{ 
    [sender setBackgroundColor:[UIColor redColor]]; 
} 

-(void)doSomething:(UIButton*)sender 
{ 
double delayInSeconds = 0.3; 
    dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC)); 
    dispatch_after(popTime, dispatch_get_main_queue(), ^(void){ 
     [sender setBackgroundColor:[UIColor redColor]]; 
    }); 
    //do something 

} 

Answer 4

当您设置按钮的TintColor它工作时突出显示

[YourButton setTintColor:[UIColor color]]; 

Answer 5

您可以使用此方法创建固体UII指定颜色的法师，然后将其应用于您的按钮。我已经为UIImage做了一个类别来做到这一点。

+ (UIImage *)imageWithColor:(UIColor *)color size:(CGSize)size 
{ 
    UIGraphicsBeginImageContext(size); 
    CGContextRef context = UIGraphicsGetCurrentContext(); 

    CGContextSetFillColorWithColor(context, color.CGColor); 
    CGContextFillRect(context, (CGRect){.size = size}); 

    UIImage *image = UIGraphicsGetImageFromCurrentImageContext(); 
    UIGraphicsEndImageContext(); 

    return image; 
} 

+ (UIImage *)imageWithColor:(UIColor *)color 
{ 
    return [UIImage imageWithColor:color size:CGSizeMake(1, 1)]; 
} 

用法：

[button setBackgroundImage:[UIImage imageWithColor:[UIColor redColor]] 
        forState:UIControlStateNormal]; 

由于Matthias指出的那样，你可以安全地使用1x1图片为您的按钮背景 - 它会被拉伸，以填充按钮。

Answer 6

斯威夫特

扩展的UIButton，让你指定的背景颜色为每一个状态：

https://github.com/acani/UIButtonBackgroundColor

请注意，iPhone 6，再加上你应该改变以下，在延伸中。快速类，这将修复它的所有版本：

//let rect = CGRect(x: 0, y: 0, width: 0.5, height: 0.5) comment this line 
    let rect = CGRect(x: 0, y: 0, width: 1, height: 1)