将图像添加到子类化的 UIImageView

Question

我正在尝试从子类化的UIImageView添加点击手势，然后从视图控制器控制点击。我没有收到任何编译错误，但"addSubview"没有显示任何图像。如何使UIImageView显示？

如果我尝试从子类化的 UIImageVIew 控制点击和平移手势，我没有问题，但我想从视图控制器控制这些功能

相关代码如下所示。

UIImageView 子类

- (id)initWithCoder:(NSCoder *)aDecoder
{
    self = [super initWithCoder:aDecoder];
    if (self)
   {
    //self.userInteractionEnabled = YES;
    previewController = [[PreviewController alloc]init];
    [previewController self];
    [self addSubview:character];
    // Tap Initialization code
    UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:(PreviewController *)self.previewController action:@selector(addCharacter:)];
    [self addGestureRecognizer:tap];
    self.userInteractionEnabled = YES;
   }
    return self;
}

视图控制器

- (void)addCharacter:(UITapGestureRecognizer *)t
{
    NSLog(@"add character");
    imageNSArray = [NSMutableArray array];
    uiImg = [UIImage imageNamed:@"homer.png"];
    CGPoint loc = [t locationInView:self.view];
    character = [[UIImageView alloc] initWithImage:uiImg];
    character.center = loc;
    [imageNSArray addObject:character];
    //Locate the imageNSArray on frameImageView area only.
    [self.view addSubview:character];     
    UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithTarget:self    action:@selector(panCharacter:)];
    [self.character addGestureRecognizer:pan];
    character.userInteractionEnabled = YES;
}

Answer 1

将

视图放在子类化图像视图后面。将手势识别应用于新视图。您可以从新视图中控制点击手势。如果我不清楚，或者是否需要更多信息，请告诉我。

Answer 2

我认为你想要的是..你想在用户点击屏幕时显示图像。执行以下步骤：1. 将点击手势识别器拖放到视图控制器的默认视图上。2. 连接 （ctrl +） 手势识别器与视图控制器.m

看看这段代码。（刚刚修改了您的代码）

- (IBAction)onTap:(UITapGestureRecognizer *)sender {
    NSLog(@"add character");
    UIImage * uiImg = [UIImage imageNamed:@"sel.png"];
    CGPoint loc = [sender locationInView:self.view];
    UIImageView * character = [[UIImageView alloc] initWithImage:uiImg];
    character.center = loc;

    [self.view addSubview:character];
}

让我知道这是否不是你想要的...

编辑最好去这个代码...无需执行上述步骤。

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(onTap:)];
    [self.view addGestureRecognizer:tap];
    self.view.userInteractionEnabled = YES;
}
- (void)onTap:(UITapGestureRecognizer *)sender
{
    NSLog(@"add character");
    UIImage * uiImg = [UIImage imageNamed:@"sel.png"];
    CGPoint loc = [sender locationInView:self.view];
    UIImageView * character = [[UIImageView alloc] initWithImage:uiImg];
    character.center = loc;
    [self.view addSubview:character];
}