一，通过按钮的事件来设置背景色
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- (
void
)viewDidLoad {
[
super
viewDidLoad];
UIButton *button1 = [[UIButton alloc] initWithFrame:CGRectMake(50, 200, 100, 50)];
[button1 setTitle:
@"button1"
forState:UIControlStateNormal];
button1.backgroundColor = [UIColor orangeColor];
[button1 addTarget:
self
action:
@selector
(button1BackGroundHighlighted:) forControlEvents:UIControlEventTouchDown];
[button1 addTarget:
self
action:
@selector
(button1BackGroundNormal:) forControlEvents:UIControlEventTouchUpInside];
[
self
.view addSubview:button1];
}
// button1普通状态下的背景色
- (
void
)button1BackGroundNormal:(UIButton *)sender
{
sender.backgroundColor = [UIColor orangeColor];
}
// button1高亮状态下的背景色
- (
void
)button1BackGroundHighlighted:(UIButton *)sender
{
sender.backgroundColor = [UIColor greenColor];
}
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二,通过把颜色转换为UIImage来作为按钮不同状态下的背景图片
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- (
void
)viewDidLoad {
[
super
viewDidLoad];
UIButton *button2 = [[UIButton alloc] initWithFrame:CGRectMake(170, 200, 100, 50)];
[button2 setTitle:
@"button2"
forState:UIControlStateNormal];
[button2 setBackgroundImage:[
self
imageWithColor:[UIColor redColor]] forState:UIControlStateNormal];
[button2 setBackgroundImage:[
self
imageWithColor:[UIColor grayColor]] forState:UIControlStateHighlighted];
[
self
.view addSubview:button2];
}
// 颜色转换为背景图片
- (UIImage *)imageWithColor:(UIColor *)color {
CGRect rect = CGRectMake(0.0f, 0.0f, 1.0f, 1.0f);
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, [color CGColor]);
CGContextFillRect(context, rect);
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return
image;
}
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三
1.首先，添加一个按钮在界面上，我们先设置好普通和高亮状态时的文字，还有圆角
UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(100, 100, 100, 40)]; [button setTitle:@"normal" forState:UIControlStateNormal]; [button setTitle:@"highlighted" forState:UIControlStateHighlighted]; [button setBackgroundColor:[UIColor redColor]]; button.layer.cornerRadius = 10.0f; button.layer.masksToBounds = YES; [self.view addSubview:button]; // 添加观察者方法 [self addObserver:button]; 2.添加观察者
/**
* 添加观察者
*
* @param button 需要设置的按钮
*/
- (void)addObserver:(UIButton *)button {
[button addObserver:self forKeyPath:@"highlighted" options:NSKeyValueObservingOptionNew context:nil]; } 3.接下来就是实现观察者方法
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary<NSString *,id> *)change context:(void *)context { UIButton *button = (UIButton *)object; if ([keyPath isEqualToString:@"highlighted"]) { if (button.highlighted) { [button setBackgroundColor:[UIColor blueColor]]; return; } [button setBackgroundColor:[UIColor redColor]]; } } 这样我们就能在不使用图片的前提下，实现设置高亮和普通状态下的背景颜色
看下具体的效果