CYLTabBarController 第七篇（Tabbar底部

以下笔记内容仅供个人参考，如有理解错误，请高抬贵手，仙人指路，互相学习进步...

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

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

解读UIControl+CYLTabBarControllerExtention.h,

UIControl+CYLTabBarControllerExtention.m

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

UIControl+CYLTabBarControllerExtention文件

#import <UIKit/UIKit.h>

@interface UIControl (CYLTabBarControllerExtention)

- (UIView *)cyl_tabBadgeView;
- (UIImageView *)cyl_tabImageView;
- (UILabel *)cyl_tabLabel;

/*!
 * 调用该方法前已经添加了系统的角标，调用该方法后，系统的角标并未被移除，只是被隐藏，调用 `-cyl_removeTabBadgePoint` 后会重新展示。
 */
- (void)cyl_showTabBadgePoint;
- (void)cyl_removeTabBadgePoint;
- (BOOL)cyl_isShowTabBadgePoint;

@property (nonatomic, strong, setter=cyl_setTabBadgePointView:, getter=cyl_tabBadgePointView) UIView *cyl_tabBadgePointView;
@property (nonatomic, assign, setter=cyl_setTabBadgePointViewOffset:, getter=cyl_tabBadgePointViewOffset) UIOffset cyl_tabBadgePointViewOffset;

@end

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

@implementation UIControl (CYLTabBarControllerExtention)

- (void)cyl_showTabBadgePoint {
    [self cyl_setShowTabBadgePointIfNeeded:YES];
}

- (void)cyl_removeTabBadgePoint {
    [self cyl_setShowTabBadgePointIfNeeded:NO];
}

- (BOOL)cyl_isShowTabBadgePoint {
    return !self.cyl_tabBadgePointView.hidden;
}

- (void)cyl_setShowTabBadgePointIfNeeded:(BOOL)showTabBadgePoint {
    @try {
        [self cyl_setShowTabBadgePoint:showTabBadgePoint];
    } @catch (NSException *exception) {
        NSLog(@"CYLPlusChildViewController do not support set TabBarItem red point");
    }
}

- (void)cyl_setShowTabBadgePoint:(BOOL)showTabBadgePoint {
    if (showTabBadgePoint && self.cyl_tabBadgePointView.superview == nil) {
        [self addSubview:self.cyl_tabBadgePointView];
        [self bringSubviewToFront:self.cyl_tabBadgePointView];
        self.cyl_tabBadgePointView.layer.zPosition = MAXFLOAT;
        // X constraint
        [self addConstraint:
         [NSLayoutConstraint constraintWithItem:self.cyl_tabBadgePointView
                                      attribute:NSLayoutAttributeCenterX
                                      relatedBy:0
                                         toItem:self.cyl_tabImageView
                                      attribute:NSLayoutAttributeRight
                                     multiplier:1
                                       constant:self.cyl_tabBadgePointViewOffset.horizontal]];
        //Y constraint
        [self addConstraint:
         [NSLayoutConstraint constraintWithItem:self.cyl_tabBadgePointView
                                      attribute:NSLayoutAttributeCenterY
                                      relatedBy:0
                                         toItem:self.cyl_tabImageView
                                      attribute:NSLayoutAttributeTop
                                     multiplier:1
                                       constant:self.cyl_tabBadgePointViewOffset.vertical]];
    }
    self.cyl_tabBadgePointView.hidden = showTabBadgePoint == NO;
    self.cyl_tabBadgeView.hidden = showTabBadgePoint == YES;
}

- (void)cyl_setTabBadgePointView:(UIView *)tabBadgePointView {
    if (tabBadgePointView.superview) {
        [tabBadgePointView removeFromSuperview];
    }
    
    tabBadgePointView.hidden = YES;
    objc_setAssociatedObject(self, @selector(cyl_tabBadgePointView), tabBadgePointView, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (UIView *)cyl_tabBadgePointView {
    UIView *tabBadgePointView = objc_getAssociatedObject(self, @selector(cyl_tabBadgePointView));
    
    if (tabBadgePointView == nil) {
        tabBadgePointView = self.cyl_defaultTabBadgePointView;
        objc_setAssociatedObject(self, @selector(cyl_tabBadgePointView), tabBadgePointView, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
    }
    return tabBadgePointView;
}

- (void)cyl_setTabBadgePointViewOffset:(UIOffset)tabBadgePointViewOffset {
    objc_setAssociatedObject(self, @selector(cyl_tabBadgePointViewOffset), [NSValue valueWithUIOffset:tabBadgePointViewOffset], OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

//offset如果都是正数，则往右下偏移
- (UIOffset)cyl_tabBadgePointViewOffset {
    id tabBadgePointViewOffsetObject = objc_getAssociatedObject(self, @selector(cyl_tabBadgePointViewOffset));
    UIOffset tabBadgePointViewOffset = [tabBadgePointViewOffsetObject UIOffsetValue];
    return tabBadgePointViewOffset;
}

- (UIView *)cyl_tabBadgeView {
    for (UIView *subview in self.subviews) {
        if ([subview cyl_isTabBadgeView]) {
            return (UIView *)subview;
        }
    }
    return nil;
}

- (UIImageView *)cyl_tabImageView {
    for (UIImageView *subview in self.subviews) {
        if ([subview cyl_isTabImageView]) {
            return (UIImageView *)subview;
        }
    }
    return nil;
}

- (UILabel *)cyl_tabLabel {
    for (UILabel *subview in self.subviews) {
        if ([subview cyl_isTabLabel]) {
            return (UILabel *)subview;
        }
    }
    return nil;
}

#pragma mark - private method

- (UIView *)cyl_defaultTabBadgePointView {
    UIView *defaultRedTabBadgePointView = [UIView cyl_tabBadgePointViewWithClolor:[UIColor redColor] radius:4.5];
    return defaultRedTabBadgePointView;
}

@end

** CYLTabBarControllerExtention总结：**

1、自定义了一个UIControl的分类，实现runtime添加了badgeView视图属性，以及控制是否badge视图是否显示，以及控制badge视图View的偏移设置