APP入口的 UITabBarController【A】

创建方式和正常方式一样，可以使用代码，也可以使用storyboard创建

UITabBarController【A】

功能视图里的 UITabBarController【B】

由视图控制器VC1的入口进入
我这里选择使用代码实现，因为我要自定义B的tabBarItem
在B中的tabBarItem是按钮，要取消按钮的点击效果(高亮状态)才能有比较好的视觉效果

UITabBarController【B】

1.自定义button

MyTabBarBtn.h

#import <UIKit/UIKit.h>
@interface MyTabBarBtn : UIButton

@end

MyTabBarBtn.m

#import "MyTabBarBtn.h"

@implementation MyTabBarBtn

/*
// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
- (void)drawRect:(CGRect)rect {
    // Drawing code
}
*/

- (void)setHighlighted:(BOOL)highlighted {
    // 重写方法即可取消高亮状态
}

@end

2.创建自己的UITabBarController

CusTabBarController.h

#import <UIKit/UIKit.h>

@interface CusTabBarController : UITabBarController

@end

CusTabBarController.m

#import "CusTabBarController.h"
#import "CusViewController.h"
#import "ReCallViewController.h"

#import "MyTabBarBtn.h"

@interface CusTabBarController () <UITabBarControllerDelegate>
{
    MyTabBarBtn * _btnLeft;
    MyTabBarBtn * _btnRight;
}
@end

@implementation CusTabBarController

- (void)viewDidLoad {
    [super viewDidLoad];

    // 先添加视图控制器
    UIStoryboard *story = [UIStoryboard storyboardWithName:@"faxingshi" bundle:nil];
    CusViewController * cusVC = [story instantiateViewControllerWithIdentifier:@"cusVC"];
    ReCallViewController * reCall = [story instantiateViewControllerWithIdentifier:@"reCallVC"];
    self.viewControllers = @[cusVC,reCall];
    
    // 后添加按钮
    UITabBar *tabBar = self.tabBar;
    tabBar.barTintColor = [UIColor clearColor];
    tabBar.backgroundColor = [UIColor clearColor];
    
//    UITabBarItem * leftBarItem = [tabBar.items objectAtIndex: 0];
//    UITabBarItem * rightBarItem = [tabBar.items objectAtIndex: 1];
//
//    
//    leftBarItem.selectedImage = [UIImage imageNamed: @""];
//    rightBarItem.image = [UIImage imageNamed: @""];
//    
//    leftBarItem.selectedImage = [UIImage imageNamed: @""];
//    rightBarItem.image = [UIImage imageNamed: @""];
    
    _btnLeft = [[MyTabBarBtn alloc] init];
    _btnLeft.frame = CGRectMake(0, 0, SCREEN_WIDTH/2, tabBar.frame.size.height);
    [_btnLeft setImage:[[UIImage imageNamed:@"cusBarIcon1Nor"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal] forState:UIControlStateNormal];
    [_btnLeft setImage:[[UIImage imageNamed:@"cusBarIcon1Sel"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal] forState:UIControlStateSelected];
    [_btnLeft setTitle:@"今日回访" forState:UIControlStateNormal];
    [_btnLeft setTitleColor:[UIColor colorWithHexString:@"a2a4a7"] forState:UIControlStateNormal];
    [_btnLeft setTitleColor:[UIColor whiteColor] forState:UIControlStateSelected];
    [_btnLeft setBackgroundImage:[[UIImage imageNamed:@"btnNorBG"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal] forState:UIControlStateNormal];
    [_btnLeft setBackgroundImage:[[UIImage imageNamed:@"btnSelBG"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal] forState:UIControlStateSelected];
    [_btnLeft addTarget:self action:@selector(btnClicked:) forControlEvents:UIControlEventTouchUpInside];
    [tabBar addSubview:_btnLeft];
    
    _btnRight = [[MyTabBarBtn alloc] init];
    _btnRight.frame = CGRectMake(SCREEN_WIDTH/2, 0, SCREEN_WIDTH/2, tabBar.frame.size.height);
    [_btnRight setImage:[[UIImage imageNamed:@"cusBarIcon2Nor"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal] forState:UIControlStateNormal];
    [_btnRight setImage:[[UIImage imageNamed:@"cusBarIcon2Sel"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal] forState:UIControlStateSelected];
    [_btnRight setTitle:@"我的客户" forState:UIControlStateNormal];
    [_btnRight setTitleColor:[UIColor colorWithHexString:@"a2a4a7"] forState:UIControlStateNormal];
    [_btnRight setTitleColor:[UIColor whiteColor] forState:UIControlStateSelected];
    [_btnRight setBackgroundImage:[[UIImage imageNamed:@"btnNorBG"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal] forState:UIControlStateNormal];
    [_btnRight setBackgroundImage:[[UIImage imageNamed:@"btnSelBG"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal] forState:UIControlStateSelected];
    [_btnRight addTarget:self action:@selector(btnClicked:) forControlEvents:UIControlEventTouchUpInside];
    [tabBar addSubview:_btnRight];
    
    // 默认显示今日回访
    _btnLeft.selected = YES;
    

}

- (void)btnClicked:(UIView *)sender {
    
    if ([sender isEqual:_btnLeft]) {
        if (!_btnLeft.selected) {
            self.selectedIndex = 0;
            _btnRight.selected = NO;
            _btnLeft.selected = YES;
        }

    } else if ([sender isEqual:_btnRight]) {
        self.selectedIndex = 1;
        _btnLeft.selected = NO;
        _btnRight.selected = YES;
    }
    
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

/*
#pragma mark - Navigation

// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    // Get the new view controller using [segue destinationViewController].
    // Pass the selected object to the new view controller.
}
*/

@end

3.视图跳转

由A的入口跳转到B中

// 此时必须要将 navigationBar 和 tabBar 隐藏
[self.navigationController.navigationBar setHidden:YES];
[self.tabBarController.tabBar setHidden:YES];
CusTabBarController * cusBarVC = [[CusTabBarController alloc] init];
[self.navigationController pushViewController:cusBarVC animated:YES];

如果VC1在A中，那么在VC1的 viewWillAppear 函数中添加下面代码，防止在返回的时候A的 tabBar 被隐藏

[self.tabBarController.tabBar setHidden:NO];

由B返回到A中

在B中的VC返回方法中使用下面的返回方式

[self.tabBarController.navigationController popToRootViewControllerAnimated:YES];