UIButton's imageView property and hidden/alpha value

user_653133 0
Viewed 10292

I have a UIButton that should display an activity indicator instead of an image in some situations. What I do at the moment is setting the hidden property of the button's imageView to YES and back. I also tried this with setting the alpha value to 0.0f and back to 1.0f.

This works until the state of the button changes. This resets the properties of the imageView and leads to hidden == NO and alpha == 1.0f.

Has anybody did something similar or has an idea how to hide the imageView of a button while the rest of it stays visible?

hidden alpha uibutton uikit ios
5 Answers

change the transform or select state will cause another problem, the best way is using category:

const char kNormalImage;
const char kSelectImage;
const char kDisableImage;

@interface UIButton ()

@property (nonatomic, strong) UIImage *normalImage;
@property (nonatomic, strong) UIImage *selectImage;
@property (nonatomic, strong) UIImage *disableImage;

@end

@implementation UIButton (Hidden)

- (void)setImageViewHidden:(BOOL)hidden {
    if (hidden) {
        self.normalImage = [self imageForState:UIControlStateNormal];
        self.selectImage = [self imageForState:UIControlStateSelected];
        self.disableImage = [self imageForState:UIControlStateDisabled];

        UIGraphicsBeginImageContextWithOptions(self.imageView.bounds.size, NO, 0.0);
        UIImage *blank = UIGraphicsGetImageFromCurrentImageContext();
        UIGraphicsEndImageContext();

        [self setImage:blank forState:UIControlStateNormal];
        [self setImage:blank forState:UIControlStateSelected];
        [self setImage:blank forState:UIControlStateDisabled];
    } else {
        [self setImage:self.normalImage forState:UIControlStateNormal];
        [self setImage:self.selectImage forState:UIControlStateSelected];
        [self setImage:self.disableImage forState:UIControlStateDisabled];
    }
}

- (UIImage *)normalImage {
    return objc_getAssociatedObject(self, &kNormalImage);
}

- (void)setNormalImage:(UIImage *)normalImage {
    objc_setAssociatedObject(self, &kNormalImage, normalImage,  OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (UIImage *)selectImage {
    return objc_getAssociatedObject(self, &kSelectImage);
}

- (void)setSelectImage:(UIImage *)selectImage {
    objc_setAssociatedObject(self, &kSelectImage, selectImage,  OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (UIImage *)disableImage {
    return objc_getAssociatedObject(self, &kDisableImage);
}

- (void)setDisableImage:(UIImage *)disableImage {
    objc_setAssociatedObject(self, &kDisableImage, disableImage,    OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

@end
user_57978120
Related