iOS-button利用block封裝按鈕事件【runtime 關聯】

用block封裝最常用的就是網路請求的回調，其實也可以結合category封裝button的按鈕事件，同時利用runtime的對象關聯；

UIButton+wkjButton.h 文件

#import <UIKit/UIKit.h>

typedef void(^btnClickAction)(UIButton *button);

@interface UIButton (wkjButton)
//@property(nonatomic,copy)btnClickAction blockAction;

/**
 新建button >>
 bgColor：預設白色
 fontColor：預設黑色
 */
+ (UIButton *)wkj_buttonFrame:(CGRect)frame
                       title:(NSString *)title
                     bgColor:(UIColor *)bgColor
                   fontColor:(UIColor *)fontColor
                    fontSize:(CGFloat)fontSize
                    fontBold:(BOOL)bold
                      action:(btnClickAction)actionBlock;
@end

UIButton+wkjButton.m 文件

#import "UIButton+wkjButton.h"

//關聯對象的key
static NSString *keyOfButtonMethod;

//讀取屬性 block的key【暫時無用】
//static NSString *keyOfActionBlock;

@implementation UIButton (wkjButton)

/**
 新建button >>
 bgColor：預設白色
 fontColor：預設黑色
 */
+ (UIButton *)wkj_buttonFrame:(CGRect)frame
                       title:(NSString *)title
                     bgColor:(UIColor *)bgColor
                   fontColor:(UIColor *)fontColor
                    fontSize:(CGFloat)fontSize
                    fontBold:(BOOL)bold
                      action:(btnClickAction)actionBlock{
    
    
    UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
    

    button.frame = frame;
    [button setTitle:title forState:UIControlStateNormal];
    if (bgColor) {
        button.backgroundColor = bgColor;
    }
    else{
        button.backgroundColor = [UIColor whiteColor];
    }
    
    if (fontColor) {
        [button setTitleColor:fontColor forState:UIControlStateNormal];
    }
    else{
        [button setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
    }
    
    if (bold) {
        button.titleLabel.font = [UIFont wkj_boldFontSize:fontSize];
    }
    else{
        button.titleLabel.font = [UIFont systemFontOfSize:fontSize];
    }
    
    [button addTarget:button action:@selector(wkj_buttonClick:) forControlEvents:UIControlEventTouchUpInside];
    
    ///runtime 方法關聯
    objc_setAssociatedObject(button, &keyOfButtonMethod, actionBlock, OBJC_ASSOCIATION_COPY_NONATOMIC);
    return button;
}
- (void)wkj_buttonClick:(UIButton *)button{
    ///如果用self.blockAction 要添加get set 方法，這裡是直接取到關聯的block
    
    ///通過key【keyOfMethod】獲取關聯對象
    btnClickAction block = (btnClickAction)objc_getAssociatedObject(button, &keyOfButtonMethod);
    if (block) {
        block(button);
    }
}

///如果要實現屬性讀取，添加 get set 方法
//- (btnClickAction)blockAction{
//    return objc_getAssociatedObject(self, &keyOfActionBlock);
//}
//- (void)setBlockAction:(btnClickAction)blockAction{
//    objc_setAssociatedObject(self, &keyOfActionBlock, blockAction, OBJC_ASSOCIATION_COPY_NONATOMIC);
//}
}


@end