添加 UIButton 的目标添加到 UIView 子类在 UIViewController 上不起作用

Question

我有一个自定义 UIButton 作为子视图添加到 UIView 子类中。在我的 viewController 中，我将自定义 uiview 作为子视图添加到控制器的视图中。然后我尝试向 uibutton 添加一个目标（在 viewWillLoad 内），但选择器从未被调用。

Answer 1

我只需要将layoutSubviews 中的所有逻辑移至构造函数即可。

Answer 2

确保您正在执行以下操作：

        UIButton *btn = [UIButton buttonWithType: UIButtonTypeCustom];
        btn.frame = CGRectMake(0, 0, 100, 40);
        [btn setTitle:@"Click Me" forState: UIControlStateNormal];
        [btn setBackgroundColor: [UIColor blackColor]];
        [btn setTitleColor: [UIColor whiteColor] forState: UIControlStateNormal];
        [btn addTarget:self action:@selector(buttonTap:) forControlEvents: UIControlEventTouchUpInside];
        [self.view addSubview:btn];

这将创建一个按钮，单击该按钮时该按钮将调用buttonTap 方法。

Answer 3

这是自定义视图和视图控制器逻辑

// 自定义视图

@implementation CustomUIASView

@synthesize firstButton;
@synthesize secondButton;
@synthesize thirdButton;

- (id)initWithFrame:(CGRect)frame {

 if ((self = [super initWithFrame:frame])) {

  self.alpha           = .85;
  self.backgroundColor = [UIColor blackColor];
}

  return self;
}


- (void)layoutSubviews {

  UIImage *buttonImageNormal;
  UIImage *stretchableButtonImageNormal;
//
  buttonImageNormal            = [UIImage imageNamed:@"as-bg.png"];
  stretchableButtonImageNormal = [buttonImageNormal stretchableImageWithLeftCapWidth:12 topCapHeight:0];

  self.firstButton = [UIButton buttonWithType:UIButtonTypeCustom];

  self.firstButton.frame           = CGRectMake(10, 10, 300, 50);
  self.firstButton.backgroundColor = [UIColor clearColor];

  [self.firstButton setTitleColor:RGB(16,62,30) forState:UIControlStateNormal];
  [self.firstButton setTitle:@"Watch Video" forState:UIControlStateNormal];
  [self.firstButton setBackgroundImage:stretchableButtonImageNormal forState:UIControlStateNormal];

  self.firstButton.titleLabel.font = [UIFont boldSystemFontOfSize:16.0f];

  [self addSubview:self.firstButton];

  self.secondButton = [UIButton buttonWithType:UIButtonTypeCustom];

  self.secondButton.frame           = CGRectMake(10, (10 + 50 + 5), 300, 50);
  self.secondButton.backgroundColor = [UIColor clearColor];

  [self.secondButton setTitleColor:RGB(16,62,30) forState:UIControlStateNormal];
  [self.secondButton setTitle:@"Save to My Favorites" forState:UIControlStateNormal];
  [self.secondButton setBackgroundImage:stretchableButtonImageNormal forState:UIControlStateNormal];

  self.secondButton.titleLabel.font = [UIFont boldSystemFontOfSize:16.0f];

  [self addSubview:self.secondButton];

  self.thirdButton = [UIButton buttonWithType:UIButtonTypeCustom];

  buttonImageNormal            = [UIImage imageNamed:@"social-button-bg.png"];
  stretchableButtonImageNormal = [buttonImageNormal stretchableImageWithLeftCapWidth:12 topCapHeight:0];

  self.thirdButton.frame           = CGRectMake(10, (secondButton.frame.origin.y + secondButton.frame.size.height + 5), 300, 50);
  self.thirdButton.backgroundColor = [UIColor clearColor];

  [self.thirdButton setTitleColor:RGB(16,62,30) forState:UIControlStateNormal];
  [self.thirdButton setTitle:@"Share with Friends on" forState:UIControlStateNormal];
  [self.thirdButton setBackgroundImage:stretchableButtonImageNormal forState:UIControlStateNormal];
  [self.thirdButton setContentHorizontalAlignment:UIControlContentHorizontalAlignmentLeft];

  CGRect thirdButtonFrame = thirdButton.titleLabel.frame;

  self.thirdButton.titleLabel.font = [UIFont boldSystemFontOfSize:16.0f];
  self.thirdButton.titleEdgeInsets = UIEdgeInsetsMake(thirdButtonFrame.origin.x, thirdButtonFrame.origin.y + 20, 0, 0);

  [self addSubview:self.thirdButton];

  [super layoutSubviews];
}

- (void)dealloc {
  [firstButton release];
  [secondButton release];
  [thirdButton release];
  [super dealloc];
}

@end

// 视图控制器片段

 self.uiasView = [[CustomUIASView alloc] initWithFrame:CGRectMake(0,    (self.view.frame.size.height + 270), kDefaultFrameWidth, 300)];

[self.uiasView.firstButton addTarget:self action:@selector(pushToRunwayViewController:) forControlEvents:UIControlEventTouchUpInside];

[self.view addSubview:self.uiasView];

“pushToRunwayViewController”从未被调用

Answer 4

不确定您是否自己弄清楚，但是当您将 Target:self 添加到第一个按钮时， self 是您实际的自定义视图，而不是视图控制器。

因此，如果您将 (pushToRunwayViewController) 方法移至 CustomAISView，一切都应该按预期工作。

我希望这有帮助。
罗格

Answer 5

首先，UIView 与 UIControl 不同。 UIView并不知道具体如何对待不同的用户交互，也没有实现大部分的事件处理方法。

UIControl 会为你做到这一点。它值得注意的子类是 UIButton。尝试从 UIControl 子类化以获取所有事件处理方法。对于更复杂的方式，在 UIView 的子类中子类化另一个 UIControl 但我认为这不是一个好主意。

更多高级事件处理和消息传递请看：

如何添加 UIViewController 作为以编程方式创建的 UIView 中创建的 UIButton 操作的目标？