ios - UIButton在HighLighted时不会改变图片，只会将图片设置为灰色

Question

我希望图片在用户触摸它的那一刻变成黄色。现在第一次点击时图像会变灰，释放时会变黄。第二次点击图片会立即变回红色。我怎样才能解决这个问题？

-(void)bMethod:(UIButton*)sender
{
    sender.selected = !sender.selected;    
}

- (void)viewDidLoad
{        
    [super viewDidLoad];
    UIButton *myButton = [UIButton buttonWithType:UIButtonTypeCustom];
    UIImage *buttonImage = [UIImage imageNamed:@"red.png"];
    UIImage *buttonImageSelected = [UIImage imageNamed:@"yellow.png"];
    myButton.frame = CGRectMake(200, 200, 40, 40);
    [myButton addTarget:self action:@selector(bMethod:) forControlEvents:UIControlEventTouchDown];
    [myButton setImage:buttonImage forState:UIControlStateNormal];
    [myButton setImage:buttonImageSelected forState:UIControlStateSelected];
    [myButton setImage:buttonImageSelected forState:UIControlStateHighlighted];
    [self.view addSubview:myButton];

Answer 1

我运行了你的代码，它运行良好，伙计。只需仔细检查图像名称！

编辑1：

用以下内容替换您的代码：

    -(void)bMethod:(UIButton*)sender
{
    if (sender.imageView.image != [UIImage imageNamed:@"red.png"]){
        [sender setImage:[UIImage imageNamed:@"yellow.png"] forState:UIControlStateHighlighted];
        [sender setImage:[UIImage imageNamed:@"yellow.png"] forState:UIControlStateNormal];
    }
    else{
        [sender setImage:[UIImage imageNamed:@"red.png"] forState:UIControlStateHighlighted];
        [sender setImage:[UIImage imageNamed:@"red.png"] forState:UIControlStateNormal];
    }    
}

- (void)viewDidLoad
{        
    [super viewDidLoad];
    UIButton *myButton = [UIButton buttonWithType:UIButtonTypeCustom];
    UIImage *buttonImage = [UIImage imageNamed:@"red.png"];
    myButton.frame = CGRectMake(200, 200, 40, 40);
    [myButton addTarget:self action:@selector(bMethod:) forControlEvents:UIControlEventTouchDown];
    [myButton setImage:buttonImage forState:UIControlStateNormal];
    [self.view addSubview:myButton];
}

编辑2：

-(void)bMethod:(UIButton*)sender
{
    sender.selected = !sender.selected;
    sender.highlighted = !sender.highlighted;  
}

- (void)viewDidLoad
{        
    [super viewDidLoad];
    UIButton *myButton = [UIButton buttonWithType:UIButtonTypeCustom];
    UIImage *buttonImage = [UIImage imageNamed:@"red.png"];
    UIImage *buttonImageSelected = [UIImage imageNamed:@"yellow.png"];
    myButton.frame = CGRectMake(200, 200, 40, 40);
    [myButton addTarget:self action:@selector(bMethod:) forControlEvents:UIControlEventTouchUpInside];
    myButton.adjustsImageWhenHighlighted = NO;
    [myButton setImage:buttonImage forState:UIControlStateNormal];
    [myButton setImage:buttonImageSelected forState:UIControlStateSelected];
    [myButton setImage:buttonImageSelected forState:UIControlStateHighlighted];
    [self.view addSubview:myButton];
}