Change background color of UIButton when Highlighted
Hi I want to change the UIButton background color which user Tap on the button.
I am showing background color using gradient, when user tap I need to change the gradient color.
[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开发者_运维知识库.titleLabel.textColor = [UIColor blackColor];
Changing the internal layer hierarchy of a UIButton is not recommended since it may break in a future update of the iOS. Also, it may cause Apple to reject your application. A better solution would be to create a button subclass. Here is an example of how to do it:
@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
You may need to modify it a bit to get it to do what you want but I think you get the basic idea.
Try this:
[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
}
You can use this method to create and solid UIImage of specified color and then apply it to your button. I've made a category for UIImage to do this.
+ (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)];
}
Usage:
[button setBackgroundImage:[UIImage imageWithColor:[UIColor redColor]]
forState:UIControlStateNormal];
As Matthias pointed out, you can safely use 1x1 image for your button background – it will be stretched to fill the button.
I found this AYUIButton on GitHub and it works perfectly :) Here is sample code:
[btn setBackgroundColor:[UIColor redColor] forState:UIControlStateNormal];
[btn setBackgroundColor:[UIColor blueColor] forState:UIControlStateHighlighted];
When you set the TintColor of the Button it works when highlighted
[YourButton setTintColor:[UIColor color]];
Swift
Extension for UIButton that let you specify background color for each state:
https://github.com/acani/UIButtonBackgroundColor
Please note that for iphone 6 plus you should change the following, inside the extension in the .swift class, that will fix it for all the versions:
//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)
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