Question

我正在制作适用于iPad的Kid's Book App。它有一个UIView加载UIImageView来显示UIImages（JPEG），用户可以在图像上滑动以浏览页面 - 一切正常。现在我想通过添加另一个加载PNG文件的UIImageView来添加一些页面的交互性，而在Tap Gesture上我想要为它们设置动画...下面是代码片段......

我在viewDidLoad中为UIView添加了一个Tap Gesture。 viewDidLoad调用loadPage和loadPage内部我以编程方式添加包含PNG文件的UIImageView（imageAnimation），并为其分配标签，以便我可以根据handleTap例程中的标签播放动画。出于某种原因，handleTap中的switch语句仅针对案例1执行ON，对于其他情况，handleTap例程永远不会被调用。我做错了什么？

#import "KidsViewController.h"

@implementation KidsViewController
@synthesize imageAnimation;

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
    if ([touch.view isKindOfClass:[UISlider class]] || [touch.view isKindOfClass:[UIButton class]])
    {
        return NO;
    }
    return YES;
}

- (void)handleTap:(UITapGestureRecognizer *)recognizer {

    NSLog(@"KidsViewController ==> handleTap.");

    switch (((UIGestureRecognizer *)recognizer).view.tag)      
    {
        case 1:
            //...
            NSLog(@"KidsViewController ==> handleTap. Switch Case: %d", 1);
            break;
        case 2:
            //...
            NSLog(@"KidsViewController ==> handleTap. Switch Case: %d", 2);
            break;
        case 3:
            //...
            NSLog(@"KidsViewController ==> handleTap. Switch Case: %d", 3);
            break;            
        default:
            NSLog(@"KidsViewController ==> handleTap. Switch Case: DEFAULT");
            break;
    }

}

- (void)viewDidLoad {

    pageCount=12;
    pageNum=1;

    //put imageviews in place
    imageNext.frame=CGRectMake(0,0-crop,screenwidth,screenheight+(crop*2));
    imageCurrent.frame=CGRectMake(0,0-crop,screenwidth,screenheight+(crop*2));

    [self loadPage];

    imageCurrent.image = [UIImage imageWithContentsOfFile:[self filePathForLanguage:language pageNumber:pageNum fileType:@"jpg"]];

    //TAP GESTURE
    UITapGestureRecognizer *tapRecognizer;
    tapRecognizer=[[UITapGestureRecognizer alloc] 
                   initWithTarget:self
                   action:@selector(handleTap:)];
    tapRecognizer.numberOfTapsRequired=1;
    tapRecognizer.numberOfTouchesRequired=1;
    [self.imageAnimation addGestureRecognizer:tapRecognizer];
    tapRecognizer.delegate = self;
    [tapRecognizer release];
}

-(void)loadPage{

    imageNext.image = [UIImage imageWithContentsOfFile:[self filePathForLanguage:language pageNumber:pageNum fileType:@"jpg"]]; //[UIImage imageWithContentsOfFile:pathFilename];

    switch (pageNum)      
    {
        case 1:
            //...
            NSLog(@"KidsViewController ==> loadPage. Switch Case: %d", pageNum);
            UIImage *image = [UIImage imageNamed:@"P3-stilts_00000.png"];
            CGRect frame = CGRectMake(0, 0, image.size.width, image.size.height);
            imageAnimation = [[UIImageView alloc] initWithFrame:frame];
            imageAnimation.userInteractionEnabled = YES;
            imageAnimation.image = image;
            imageAnimation.tag = pageNum;
            [self.view addSubview:imageAnimation];
            [image release];
            break;
        case 2:
            //...
            NSLog(@"KidsViewController ==> loadPage. Switch Case: %d", pageNum);
            imageAnimation.image = nil;
            [imageAnimation setCenter:CGPointMake(-100,-100)];
            break;
        case 3:
            //...
            NSLog(@"KidsViewController ==> loadPage. Switch Case: %d", pageNum);
            UIImage *image3 = [UIImage imageNamed:@"bug.png"];
            CGRect bugFrame = CGRectMake(0, 0, image3.size.width, image3.size.height);
            imageAnimation = [[UIImageView alloc] initWithFrame:bugFrame];
            imageAnimation.userInteractionEnabled = YES;
            imageAnimation.image = image3;
            imageAnimation.tag = pageNum;
            [self.view addSubview:imageAnimation];
            [image3 release];
            break;            
        default:
            NSLog(@"KidsViewController ==> loadPage. Switch Case: DEFAULT");
            [imageAnimation setCenter:CGPointMake(-100,-100)];
            break;
    }
}

- (void)dealloc {
    [setupViewController release];
    [imageCurrent release];
    [imageNext release];
    [imageShadow release];
    [imageMenuBar release];
    [imageAnimation release];
    [super dealloc];
}

@end

Answer 1

您始终会获得 self.view 的标记。默认情况下，标记为 0 。因此切换跳转到默认选项。

您可以将识别器添加到 imageAnimation ，它会正常工作。

Answer 2

你的问题可能就在这里：

switch (((UIGestureRecognizer *)recognizer).view.tag)

当您注册该手势识别器时，您将添加到视图控制器的视图中，而不是您正在追踪的图像视图：

[self.view addGestureRecognizer:tapRecognizer];

如果您尝试获取被点击的视图，请考虑使用类似

的内容

CGPoint point = [tapRecognizer locationInView:tapRecognizer.view];
UIView *viewThatWasTouched = [tapRecognizer.view hitTest:point withEvent:nil];

UIImageView标记和点击手势问题

2 个答案: