来自自定义UIControl子类的转发事件

Question

My custom subclass extend UIControl (EditableImageView) Basically it contains 3 subviews:

• UIButton (UIButtonTypeCustom)
• UIImageView
• UILabel

All the class works great but now I want to connect some events generated from this class to another. In particular when the button is pressed I want to forward the event to the owner viewcontroller so that I can handle the event. The problem is that I can't figure out how to implement this behaviour. Within EditableImageView I can catch the touch event using [button addTarget:self action:@selector(buttonPressed:) forControlEvents:UIControlEventTouchUpInside] but I don't know how to forward it inside of the buttonPressed selector. I also tried to implement touchesBegan but it seems never called...

I'd like to capture the button press event from the viewcontroller in this way:

- (void)viewDidLoad {
[super viewDidLoad];

self.imageButton = [[EditableImageView alloc] initWithFrame:CGRectMake(50.0f, 50.0f, 80.0f, 80.0f)];
[imageButton addTarget:self action:@selector(buttonPressed:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:imageButton];
[imageButton setEditing:NO];

}

This is my UIControl subclass initialization method:

- (id)initWithFrame:(CGRect)frame {
    if (self = [super initWithFrame:frame]) {
        [self setBackgroundColor:[UIColor clearColor]];

        button = [UIButton buttonWithType:UIButtonTypeCustom];
        button.frame = CGRectMake(0.0f, 0.0f, frame.size.width, frame.size.height);
        [button setImage:[UIImage imageNamed:@"nene_70x70.png"] forState:UIControlStateNormal];
        [button addTarget:self action:@selector(buttonPressed:) forControlEvents:UIControlEventTouchUpInside];

        [self addSubview:button];

        transparentLabelBackground = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"editLabelBackground.png"]];
        transparentLabelBackground.hidden = YES;
        [self addSubview:transparentLabelBackground];

        // create edit status label
        editLabel = [[UILabel alloc] initWithFrame:CGRectZero];
        editLabel.hidden = YES;
        editLabel.userInteractionEnabled = NO;  // without this assignment the button will not be clickable
        editLabel.textColor = [UIColor whiteColor];
        editLabel.backgroundColor = [UIColor clearColor];
        editLabel.textAlignment = UITextAlignmentLeft;
        UIFont *labelFont = [UIFont systemFontOfSize:16.0];
        editLabel.font = labelFont;     
        editLabel.text = @"edit"; 
        labelSize = [@"edit" sizeWithFont:labelFont];

        [self addSubview:editLabel];
    }

    return self;
}

Thanks.

Answer 1

I solved in this way:

EditableImageView.h:

@interface EditableImageView : UIControl {
UIButton *button;
UIImageView *transparentLabelBackground;
UILabel *editLabel;
CGSize labelSize;

BOOL editing;
}

@property (nonatomic, retain) UIButton *button;
@property (nonatomic, retain) UILabel *editLabel;
@property (nonatomic, retain) UIImageView *transparentLabelBackground;
@property (nonatomic, getter=isEditing) BOOL editing;

- (void)buttonPressed:(id)sender;
@end

EditableImageView.m:

 (id)initWithFrame:(CGRect)frame {
    if (self = [super initWithFrame:frame]) {
        [self setBackgroundColor:[UIColor clearColor]];

        button = [UIButton buttonWithType:UIButtonTypeCustom];
        button.frame = CGRectMake(0.0f, 0.0f, frame.size.width, frame.size.height);
        [button setImage:[UIImage imageNamed:@"nene_70x70.png"] forState:UIControlStateNormal];
        [button addTarget:self action:@selector(buttonPressed:) forControlEvents:UIControlEventTouchUpInside];
        .......
    }
}


- (void)buttonPressed:(id)sender {
[self sendActionsForControlEvents:UIControlEventTouchUpInside];
}

MyController.m:

- (void)viewDidLoad {
    [super viewDidLoad];
    self.imageButton = [[EditableImageView alloc] initWithFrame:CGRectMake(50.0f, 50.0f, 80.0f, 80.0f)];
    [imageButton addTarget:self action:@selector(buttonPressed:) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:imageButton];
}

- (void)buttonPressed:(id)sender {
    NSLog(@"buttonPressed!");
}