Question

嘿，我正在尝试在用户触摸ImageView时更改图像。目前ImageView的图像为“heart1.png”，所以当我触摸屏幕上的ImageViewer时，它将变为“heart2.png”这是我的代码，非常感谢帮助：

-(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint location = [touch locationInView:self.view];
    if (location.x >= imageView.frame.origin.x && location.x <= imageView.frame.origin.x + imageView.frame.size.height && location.y >= imageView.frame.origin.y && location.y <= imageView.frame.origin.y + imageView.frame.size.height) {
        imageView.image = [UIImage imageNamed:@"heart2.png"];
    }    
}

Answer 1

这对我来说似乎是一个问题：

if（location.x＆gt; = imageView.frame.origin.x＆amp;＆amp; location.x＆lt; = imageView.frame.origin.x + imageView.frame.size。 - ＆gt; height ＆LT; -

可能是宽度：）

Answer 2

为什么不通过使用界面构建在图像上放置自定义（即不可见）UIButton来简化事情，而不是愚弄检查边界矩形的坐标？然后，您可以将touchesUpInside连接到IBAction方法。然后你的代码中没有尴尬的if语句，也不会有这样的错误发生的机会。

Answer 3

请考虑使用UIButton。

[button setImage:[UIImage imageNamed:@"heart1.png"] forState:UIControlStateNormal];
[button setImage:[UIImage imageNamed:@"heart2.png"] forState:UIControlStateHighlighted];

Answer 4

无需查找view的位置，您无需移动UIImageView。只需这样做：

-(void)viewDidLoad 
{
    // imageView is your UIImageView
    imageView = [[UIImageView alloc]initWithFrame:CGRectMake(0.0, 0.0, 320.0, 480.0)];
    [imageView setImage:[UIImage imageNamed:@"heart1.png"]];
    [imageView setUserInteractionEnabled:YES];

    // Make sure userInteractionEnable is set to be YES; otherwise the touch event will be happen on UIView not on ImageView;
   [self.view addSubview:imageView];
}
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event 
{
    UITouch *touch = [[event allTouches]anyObject];
    if([touch view]==imageView)
        [imageView setImage:[UIImage imageNamed:@"heart2.png"]];
}

在TouchesBegan上更改图像

4 个答案: