IBAction子检查是否隐藏图像

Question

我想通过单击按钮来检查子视图的图像是否隐藏。日志确实显示，但我无法以某种方式获得图像的隐藏状态。

这里怎么回事？希望你能帮助我！

viewDidLoad中：

SubSlide1Hoofdstuk3 *subslide1 = [[SubSlide1Hoofdstuk3 alloc] init]; 
CGRect frame = self.view.frame; 
frame.origin.x = 0; 
frame.origin.y = 0; 
subslide1.view.frame = frame; 

// This works finaly 
UIImageView *zwart = subslide1.imageZwart; 
[zwart setImage:[UIImage imageNamed:@"imageblack.jpg"]]; 
[subslide1.b1 addTarget:self action:@selector(switchImageZwart:) forControlEvents:UIControlEventTouchUpInside]; 

[_scrollView addSubview:subslide1.view]; 

的IBAction为检查在子视图图像隐藏：

-(IBAction)switchImageZwart:(id)sender 
{ 
    SubSlide1Hoofdstuk3 *switchactie = [[SubSlide1Hoofdstuk3 alloc] init]; 
    UIImageView *wit = switchactie.imageWit; 
    UIImageView *zwart = switchactie.imageZwart; 

    if(zwart.hidden == YES) { 
     NSLog(@"Image black is hidden!"); 
    } else if(wit.hidden == YES) { 
     NSLog(@"Image white is hidden!"); 
    } else { 
     NSLog(@"Can't say... :("); 
    } 
} 

Answer 1

这里的问题是，你的-(IBAction)switchImageZwart:(id)sender方法内部创建的SubSlide1Hoofdstuk3一个新实例，并检查其属性（UIImageViews）而不是检查您在viewDidLoad:上创建的实际UIImageView对象。你想要的实际是持有对subslide1的引用，并检查它。

Ps。由于按钮调用检查方法实际上是对你subslide1的子视图，你可以得到这样的引用：

SubSlide1Hoofdstuk3 *switchactie = [sender superView]; 

编辑：你的实际代码的一个例子：

在.h文件中

：

@synthesize subslide1; 

- (void)viewDidLoad 
{ 
    //... 
    self.subslide1 = [[SubSlide1Hoofdstuk3 alloc] init]; 
    CGRect frame = self.view.frame; 
    frame.origin.x = 0; 
    frame.origin.y = 0; 
    self.subslide1.view.frame = frame; 

    // This works finaly 
    UIImageView *zwart = self.subslide1.imageZwart; 
    [zwart setImage:[UIImage imageNamed:@"imageblack.jpg"]]; 
    [self.subslide1.b1 addTarget:self action:@selector(switchImageZwart:) forControlEvents:UIControlEventTouchUpInside]; 

    [_scrollView addSubview:self.subslide1.view]; 

} 


-(IBAction)switchImageZwart:(id)sender 
{ 
    SubSlide1Hoofdstuk3 *switchactie = self.subslide1; 
    UIImageView *wit = switchactie.imageWit; 
    UIImageView *zwart = switchactie.imageZwart; 

    if(zwart.hidden == YES) { 
     NSLog(@"Image black is hidden!"); 
    } else if(wit.hidden == YES) { 
     NSLog(@"Image white is hidden!"); 
    } else { 
     NSLog(@"Can't say... :("); 
    } 
}