RDVTabBarController是一個(gè)用來(lái)自定義tabbar的三方庫(kù)，使用簡(jiǎn)單，不過(guò)隱藏tabbar的時(shí)候比較麻煩
用法：與系統(tǒng)tabbar基本一樣。
隱藏：可以在RootViewController的viewWillAppear與viewWillDisappear中判斷tabbar的隱藏與顯示
問(wèn)題：出現(xiàn)過(guò)一個(gè)詭異的bug，有時(shí)候跳轉(zhuǎn)到tabbar的root頁(yè)面中，tabbar沒(méi)有出現(xiàn)，還沒(méi)有跟蹤到問(wèn)題的根由所在。

-(void) viewWillAppear:(BOOL)animated
{
    [self.navigationController setNavigationBarHidden:self.hideNavigationBar animated:YES];
    if (!self.navigationController) {
        [[self rdv_tabBarController] setTabBarHidden:YES animated:NO];
        return;
    }
    if (self.navigationController.viewControllers.count <= 1) {
        [[self rdv_tabBarController] setTabBarHidden:NO animated:NO];
        return;
    }   
    [super viewWillAppear:animated];
    if (self) {
        [DataConversion beginLogPageView:NSStringFromClass([self class])];
    }
}

-(void)viewWillDisappear:(BOOL)animated
{
    if (self) {
        [DataConversion endLogPageView:NSStringFromClass([self class])];
    }
    id cla=[self.navigationController.viewControllers lastObject];
    if ([cla isKindOfClass:[HomeViewController class]]||[cla isKindOfClass:[YewuViewController class]]||[cla isKindOfClass:[SettingViewController class]]||[cla isKindOfClass:[MessageViewController class]]) {
        [[self rdv_tabBarController] setTabBarHidden:NO animated:NO];
    }
    if (!self.navigationController) {
        [[self rdv_tabBarController] setTabBarHidden:YES animated:NO];
        return;
    }
    
    if (!self.navigationController.viewControllers.count) {
        TabBarViewController *tab=(TabBarViewController *)[EquipmentInformation getCurrentViewController];
        if ([tab isKindOfClass:[TabBarViewController class]]) {
            tab.tabBarHidden=NO;
        }
    }
    [super viewWillDisappear:animated];
}

RDVTabBarController由RDVTabBarController、RDVTabBar、RDVTabBarItem組成

//tabbar圖片，對(duì)selectedImage與unselectedImage進(jìn)行賦值 與 finishedSelectedImage、finishedUnselectedImage屬性一致
- (void)setFinishedSelectedImage:(UIImage *)selectedImage withFinishedUnselectedImage:(UIImage *)unselectedImage

//title屬性，tabbar的title
@property (nonatomic, copy) NSString *title;

然后在 RDVTabBarItem:UIControl 類(lèi)中的

- (void)drawRect:(CGRect)rect 

方法中用coreText對(duì)img與title進(jìn)行繪制

RDVTabBar : UIView 為RDVTabBarItem添加點(diǎn)擊事件，添加_backgroundView

//設(shè)置item的frame
- (void)layoutSubviews 

//為item添加點(diǎn)擊事件并添加到RDVTabBar上
- (void)setItems:(NSArray *)items {
    for (RDVTabBarItem *item in _items) {
        [item removeFromSuperview];
    }
    _items = [items copy];
    for (RDVTabBarItem *item in _items) {
        [item addTarget:self action:@selector(tabBarItemWasSelected:) forControlEvents:UIControlEventTouchDown];
        [self addSubview:item];
    }
}

RDVTabBarController : UIViewController

//添加tabbar上的所有viewController，對(duì)RDVTabBarItem進(jìn)行初始化，并對(duì)[self tabBar]的items屬性賦值。
@property (nonatomic, copy) IBOutletCollection(UIViewController) NSArray *viewControllers;
- (void)setViewControllers:(NSArray *)viewControllers {
        NSMutableArray *tabBarItems = [[NSMutableArray alloc] init];
        for (UIViewController *viewController in viewControllers) {
            RDVTabBarItem *tabBarItem = [[RDVTabBarItem alloc] init];
            [tabBarItem setTitle:viewController.title];
            [tabBarItems addObject:tabBarItem];
            [viewController rdv_setTabBarController:self];
        }
        [[self tabBar] setItems:tabBarItems];
}
//返回某個(gè)viewController
@property (nonatomic, weak) UIViewController *selectedViewController;