iOS-个人整理15 - 标签视图控制器--UITabBarCo

一、UITabBarController

微信底部那一排 微信、通讯录、发现、朋友圈，就是UITabBarController
它上面的控制的四个视图控制器是平级的，一般情况下将self.window.rootViewController设置为UITabBarController
然后在UITabBarController上面添加UINavigationController
UINavigationController上面添加一般的UIViewController
UITabBarController-->UINavigationController-->UIViewController

二、属性和方法

UITabBar的高度是49，最多显示5个UITabBarItem，超过5个会增加一个更多按钮。

 #import "RootTabBarController.h" 
#import "SecondViewController.h" 

    //创建一个ViewController加到NavigationController上  
    //再将NavigationController加到TabBarController上  
  
    RootViewController *rootVC = [[RootViewController alloc]init]; 
 
    UINavigationController *navigationC = [[UINavigationController alloc]initWithRootViewController:rootVC];  
      
    //创建UITabBarController  
    UITabBarController *myTabBar = [UITabBarController new];  
      
    //将导航控制器放入tabBar  
    myTabBar.viewControllers = @[navigationC];  
      
    //设置底部的item标题，这个字很小  
    navigationC.tabBarItem.title = @"根";  
      
    //设置图片，这里图片大小不能自适应，最好把图片裁好 40*40，照片还有设置渲染效果，背景色会影响照片显示  
    navigationC.tabBarItem.image = [[UIImage imageNamed:@"b3.gif"]  
    imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];;  
      
    //设置tabBar的字体颜色  
    myTabBar.tabBar.tintColor = [UIColor colorWithRed:109/255.0 green:211/255.0 blue:206/255.0 alpha:1];  
      
    //设置tabbar背景颜色  
    myTabBar.tabBar.barTintColor =  [UIColor colorWithRed:200/255.0 green:233/255.0 blue:160/255.0 alpha:1];  
  
    //是否半透明  
    myTabBar.tabBar.translucent = NO;  
  
    //将tabBarController设置为根视图控制器  
    self.window.rootViewController = myTabBar;  
      
    //把SecondView添加  
    SecondViewController *secondVC = [[SecondViewController alloc]init];  
    UINavigationController *secondNavC = [[UINavigationController alloc]initWithRootViewController:secondVC];  
      
    //设置标题  
    secondNavC.tabBarItem.title = @"second";  
      
    //设置item角标，右上角的红色数字，未读消息数  
    secondNavC.tabBarItem.badgeValue = @"10";  
  
    //当前被选中的页面/按钮    
    myTabBar.selectedIndex = 0;  
  
    //将第三个界面加入  
    tabbar ThirdViewController *thirdVC = [[ThirdViewController alloc]init];   
    UINavigationController *thirdNavC = [[UINavigationController alloc]initWithRootViewController:thirdVC];   
    thirdNavC.tabBarItem.title = @"third";   
    //将所有视图加入  
    tabbar myTabBar.viewControllers = @[navigationC,secondNavC,thirdNavC];   
    //设置默认页   
    myTabBar.selectedIndex = 1;   
    //设置为根视图控制器 RootTabBarViewController *rootTabBarVC = [[RootTabBarViewController alloc]init];   
    self.window.rootViewController = rootTabBarVC  

UITabBarController 自带逻辑，点击下面的分区bar会自动跳转到相应的NavigationController下的ViewController

这是UITabBarItem的样式和对应的枚举值

三、自定义UITabBarViewController

系统的TabBar有时不能满足我们的需求，我们可以更改它的外观。
自定义一个UIView的视图，贴在UITabBar的View上
将UITabBarController的tabbar属性的hidden设置为YES，就可以隐藏原有的tabbar显示了。

先写自定义的tabBarUIview，思路是做一个底部横条视图，给上面加上自定义的button，给button加上方法，该方法来改变系统的UITabBarController的selectedIndex值。
这里涉及一个页面间传值的问题，可以使用block或者协议方法
customTabBarView.h

#import <UIKit/UIKit.h>  
  
//block传值  
  
typedef void(^passValue)(NSInteger tag);  
  
@protocol CustomTabBarDelegate <NSObject>  
  
//把btn的tag传出去的方法  
-(void)selectedIndexWithTag:(NSInteger)tag;  
  
@end  
  
@interface CustomTabBarView : UIView  
  
@property (nonatomic,copy)passValue passValueTag;  
@property (nonatomic,assign)id <CustomTabBarDelegate>delegate;  
  
@end  

customTabBarView.m

#import "CustomTabBarView.h"  
  
@implementation CustomTabBarView  
  
//创建按钮  
-(void)createSubViews  
{  
      
    for (int i = 0; i < 2; i ++) {  
        //初始化按钮  
        UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];  
        [btn setTitle:[@(i) stringValue] forState:UIControlStateNormal];  
          
        //点击时的样式  
        [btn setTitle:@"选" forState:UIControlStateHighlighted];  
        [btn setTitle:@"33" forState:UIControlStateFocused];  
        [btn setImage:[[UIImage imageNamed:@"b33"]imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal] forState:UIControlStateSelected];  
        [btn setTitle:@"" forState:UIControlStateSelected];  
          
        //选中状态  
//        btn.selected = NO;  
          
        //通过tag值来确定我们点击的是哪一个按钮，来切换到对应的视图控制器  
        [btn setTag:1000+i];  
          
        //设置点击方法  
        [btn addTarget:self action:@selector(customSelectedIndex:) forControlEvents:UIControlEventTouchDown];  
          
        //设置frame  
        btn.frame = CGRectMake((414)/2*i, 0, 414/2, 50);  
          
          
        [self addSubview:btn];  
    }  
}  
  
//按钮的回调方法  
-(void)customSelectedIndex:(UIButton*)sender  
{  
    for (int  i = 0; i< 2; i++) {  
        UIButton *btn = (UIButton*)[self viewWithTag:1000+i];  
        btn.selected = NO;  
    }  
      
    sender.selected = YES;  
      
//    判断在指定的代理类中是否实现了该协议方法  
//    确保执行时无此方法时不崩溃  
    if([self.delegate respondsToSelector:@selector(selectedIndexWithTag:)])  
    {  
        [self.delegate selectedIndexWithTag:(sender.tag - 1000)];  
    }  
    else  
    {  
        NSLog(@"selectIndexWithTag该方法没有实现");  
    }  
      
    //调用block方法  
    //self.passValueTag(sender.tag - 1000);  
      
}  
  
//初始化自定义的UIView  
-(instancetype)initWithFrame:(CGRect)frame  
{  
    //设置frame  
    frame = CGRectMake(0, 736-50, 414, 50);  
      
    self = [super initWithFrame:frame];  
    if (self) {  
        [self createSubViews];  
        self.backgroundColor = [UIColor colorWithRed:109/255.0 green:211/255.0 blue:206/255.0 alpha:1];  
    }  
      
    return self;  
}  
  
@end  

在RootTabBController.m中添加自定义的视图，并隐藏原本的TabBar
这里的secondViewController和FirstViewController就是跳转后显示的VC

#import "RootTabBarController.h"  
#import "FirstViewController.h"  
#import "SecondViewController.h"  
#import "CustomTabBarView.h"  
  
//导入协议  
@interface RootTabBarController ()<CustomTabBarDelegate>  
  
@end  
  
@implementation RootTabBarController  
  
-(void)viewDidLoad  
{  
    [super viewDidLoad];  
      
    //创建视图控制器  
    FirstViewController *firstVC = [[FirstViewController alloc]init];  
    UINavigationController *firstNavC = [[UINavigationController alloc]initWithRootViewController:firstVC];  
    firstVC.view.backgroundColor = [UIColor colorWithRed:109/255.0 green:211/255.0 blue:206/255.0 alpha:1];  
      
    SecondViewController *secondVC = [[SecondViewController alloc]init];  
    UINavigationController *secondNavC = [[UINavigationController alloc]initWithRootViewController:secondVC];  
    secondVC.view.backgroundColor = [UIColor colorWithRed:200/255.0 green:233/255.0 blue:160/255.0 alpha:1];  
      
    //给tabBarController添加子控制器  
    [self addChildViewController:firstNavC];  
    [self addChildViewController:secondNavC];  
      
    //使用自定义的tabbar先把系统的隐藏掉  
    self.tabBar.hidden = YES;  
      
    //初始化自定义的tabbar  
    CustomTabBarView *customView = [[CustomTabBarView alloc]initWithFrame:CGRectZero];  
    [self.view addSubview:customView];  
      
    //指定代理  
    customView.delegate = self;  
      
    //设置block内容  
    customView.passValueTag = ^(NSInteger tag)  
    {  
        self.selectedIndex = tag;  
    };     
}  
//实现代理方法  
- (void)selectedIndexWithTag:(NSInteger)tag  
{  
    self.selectedIndex = tag;  
}  
@end  

做的比较丑和简单