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使用方法教程

使用方法及教程，查看项目源码github地址：https://github.com/ChenYilong/CYLTabBarController，非常感谢开源的作者，开源促进社区的发展，共建和谐社会😆！

框架全部文件结构

1.CYLTabBarController
2. CYLTabBar
3.CYLPlusButton
4.UIViewController+CYLTabBarControllerExtention
5.UIView+CYLTabBarControllerExtention
6.UITabBarItem+CYLTabBarControllerExtention
7.UIControl+CYLTabBarControllerExtention
8.CYLConstants
8.总结

解读UITabBarItem+CYLTabBarControllerExtention类文件,在源码中中文注释自己的理解👇

UITabBarItem+CYLTabBarControllerExtention类文件（.h,.m）

解读UITabBarItem+CYLTabBarControllerExtention.h,

UITabBarItem+CYLTabBarControllerExtention.m

可能需要理解的知识点：
.Block代码块 【 //www.greatytc.com/p/14efa33b3562】
.类别Category扩展 【//www.greatytc.com/p/b49e02eb7eb3】
.runtime机制 【 https://github.com/Tuccuay/RuntimeSummary】
.KVC设计模式 【 //www.greatytc.com/p/45cbd324ea65】
.KVO设计模式 【 //www.greatytc.com/p/e59bb8f59302】
.异常处理机制 【//www.greatytc.com/p/f28b9b3f8e44】

UITabBarItem+CYLTabBarControllerExtention文件

#import <UIKit/UIKit.h>

@interface UITabBarItem (CYLTabBarControllerExtention)

//添加了一个tabbarButton
@property (nonatomic, readonly) UIControl *cyl_tabButton;

@end

#import "UITabBarItem+CYLTabBarControllerExtention.h"
#import <objc/runtime.h>
#import "UIControl+CYLTabBarControllerExtention.h"

@implementation UITabBarItem (CYLTabBarControllerExtention)

//设置badge值
- (void)cyl_setBadgeValue:(NSString *)badgeValue {
    [self.cyl_tabButton cyl_removeTabBadgePoint];
    [self cyl_setBadgeValue:badgeValue];
}

//获取badge视图
- (UIControl *)cyl_tabButton {
    UIControl *control = [self valueForKey:@"view"];
    return control;
}


//runtime方法交换
+ (void)load {
    [self cyl_swizzleSetBadgeValue];
}

+ (void)cyl_swizzleSetBadgeValue {
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        cyl_ClassMethodSwizzle([self class], @selector(setBadgeValue:), @selector(cyl_setBadgeValue:));
    });
}

#pragma mark - private method

BOOL cyl_ClassMethodSwizzle(Class aClass, SEL originalSelector, SEL swizzleSelector) {
    Method originalMethod = class_getInstanceMethod(aClass, originalSelector);
    Method swizzleMethod = class_getInstanceMethod(aClass, swizzleSelector);
    BOOL didAddMethod = class_addMethod(aClass,originalSelector,method_getImplementation(swizzleMethod),method_getTypeEncoding(swizzleMethod));
    if (didAddMethod) {
        class_replaceMethod(aClass,
                            swizzleSelector,
                            method_getImplementation(originalMethod),
                            method_getTypeEncoding(originalMethod));
    } else {
        method_exchangeImplementations(originalMethod, swizzleMethod);
    }
    return YES;
}

@end

UITabbarController总结：

1、自定义了一个UITabBarItem的分类，实现setBadgeValue与cyl_setBadgeValue方法交换