如何使我的图像可点击

Question

显然我很想念UIImageView和UIImage,为了在图像上注册手势(如点击/点击),我需要在uiimageview中有图像并在uiimageview上注册手势而不是在uiimage上.

所以这段代码对我有用:

- (void)drawRect:(CGRect)rect {    
    Obj *obj = ... obj has imageHref which is NSString

    UIImage *image = [UIImage imageNamed:[NSString stringWithFormat:obj.imageHref]]; 
    [image drawInRect:CGRectMake((self.frame.size.width/2) - (image.size.with/2), (self.frame.size.height / 2) - (image.size.height / 2), image.size.width, image.size.height)];

}

这给了我居中的图像,但没用,因为我希望它可以点击,所以我只是用UIImageview来做这样的:

  - (void)drawRect:(CGRect)rect {    
            Obj *obj = ... obj has imageHref which is NSString

            UIImage *image = [UIImage imageNamed:[NSString stringWithFormat:obj.imageHref]]; 

    CGRect rect1=CGRectMake((self.frame.size.width/2) - (image.size.width/2), (self.frame.size.height / 2) - (image.size.height / 2), image.size.width, image.size.height);

    UIImageView *backgroundImageView = [[UIImageView alloc] initWithImage:radioStationImage];

UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(imageTapped:)];

    [backgroundImageView addGestureRecognizer:tap];

            [backgroundImageView drawRect:rect1];

        }

我只是想让这个图像可点击以便在点击时执行某种操作,这有多难？

编辑:

我实际上是在实施:

https://github.com/andreyvit/SoloComponents-iOS/tree/master/ATPagingView

哪个提供整洁的页面滚动.但是屏幕中间的可点击图像不是第1页,第2页等.

编辑2:

今天对此有何看法？

Answer 1

您不需要自定义绘图(drawRect:).只需在加载UIImageView视图时将其添加为子视图(在Interface Builder中或loadView根据您初始化视图的方式).然后UITapGestureRecognizer,您可以在执行时添加到该视图.

正如@jackslash所说,您还需要在完成后启用图像视图的用户交互.

我相信你做的比现在复杂得多.无需自定义绘图drawRect:.不需要子类化UIImageView(链接@ madmik3引用与iOS4 +无关).可能不需要实际的UIView子类(您可以在视图控制器中执行所有这些操作),但是您可以在视图子类中执行此操作:

- (id)initWithFrame:(CGRect)frame {
  self = [super initWithFrame:frame];
  if (self) {
    Obj *obj = ... obj has imageHref which is NSString
    UIImage *image = [UIImage imageNamed:[NSString stringWithFormat:obj.imageHref]]; 
    UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake((self.frame.size.width/2) - (image.size.with/2), (self.frame.size.height / 2) - (image.size.height / 2), image.size.width, image.size.height)];
    imageView.userInteractionEnabled = YES;
    UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(imageTapped:)];
    [imageView addGestureRecognizer:tap];

    [self addSubview:imageView];
  }
  return self;
}

Answer 2

默认情况下，UIImageView其属性userInteractionEnabled设置为NO。

做：

[imageView setUserInteractionEnabled:YES];