iOS开发基础 - UITabBarController

UITabBarController

//标签栏控制器有一个标签条 是属于标签栏控制器的UITabBarController
//标签条上面的按钮tabBarItem  是属于每个界面的
HomeViewController *homeVC = [[HomeViewController alloc]init];
//tabBarItem标签项
homeVC.tabBarItem.image = [UIImage imageNamed:@"home_tabbar_icon_home"];
homeVC.title = @"首页";

SortViewController *sortVC = [[SortViewController alloc]init];
//tabBarItem未选中的图片
sortVC.tabBarItem.image = [UIImage imageNamed:@"home_tabbar_icon_channel"];
//tabBarItem下面的标题
sortVC.title = @"分类";
//tabBarItem选中的图片
sortVC.tabBarItem.selectedImage = [UIImage imageNamed:@"home_tabbar_icon_channel_sel"];

FindViewController *findVC = [[FindViewController alloc]init];
findVC.tabBarItem = [[UITabBarItem alloc]initWithTitle:@"发现" image:[UIImage imageNamed:@"home_tabbar_icon_find"] selectedImage:[UIImage imageNamed:@"home_tabbar_icon_find_sel"]];

MineViewController *mineVC = [[MineViewController alloc]init];
mineVC.title = @"我的";
mineVC.tabBarItem.image = [UIImage imageNamed:@"home_tabbar_icon_user"];
mineVC.tabBarItem.selectedImage = [UIImage imageNamed:@"home_tabbar_icon_user_sel"];
//设置提示红点

// mineVC.tabBarItem.badgeValue = @”2”;

//UITabBarController 标签栏控制器  它也是一个容器 用来管理平级界面之间的切换  继承自UIViewController
//UINavigationController 导航控制器  也是一个容器  用来管理具有明确层次关系的界面之间的切换  继承自UIViewController
UITabBarController *tabBarCon = [[UITabBarController alloc]init];
//把平级界面放到数组里面  viewControllers是UITabBarController的属性
tabBarCon.viewControllers = @[homeVC,sortVC,findVC,mineVC];
//数组中元素的顺序 就是显示的顺序

//tabBar 标签条 属于UITabBarController
//barStyle标签条的风格

// tabBarCon.tabBar.barStyle = UIBarStyleBlack;
/*
UIBarStyleDefault
UIBarStyleBlack
UIBarStyleBlackOpaque = 1, // Deprecated. Use UIBarStyleBlack
UIBarStyleBlackTranslucent = 2,
*/
//tabBar背景颜色
// tabBarCon.tabBar.barTintColor = [UIColor cyanColor];
//tabBar背景图片
tabBarCon.tabBar.backgroundImage = [UIImage imageNamed:@”home_tabbar”];
//导航条的高度 64
//标签条的高度 49

//默认选中的界面/默认显示的界面
tabBarCon.selectedIndex = 1;

// tabBarCon.selectedViewController = findVC;

//把标签栏控制器作为window的根试图
self.window.rootViewController = tabBarCon;
[self.window makeKeyAndVisible];
return YES;

UITabBarController的自定义使用

1.建立新类型 继承自UITabBarController

2.隐藏系统的标签栏 然后重写

@interface MyTabBarController ()

@end

@implementation MyTabBarController

• (void)viewDidLoad {
  [super viewDidLoad];
  //隐藏系统标签条
  self.tabBar.hidden = YES;
  [self create];
  [self createTabBar];
  }

-(void)create{
RootViewController * rootVC = [[RootViewController alloc] init];
rootVC.title = @”首页”;
SecondViewController * secondVC = [[SecondViewController alloc] init];
secondVC.title = @”第二页”;
ThirdViewController * thirdVC = [[ThirdViewController alloc] init];
thirdVC.title = @”第三页”;
FouthViewController * fouthVC = [[FouthViewController alloc] init];
fouthVC.title = @”第四页”;
LastViewController * lastVC = [[LastViewController alloc] init];
lastVC.title = @”第五页”;

self.viewControllers = @[rootVC,secondVC,thirdVC,fouthVC,lastVC];

}

-(void)createTabBar{

CGFloat width = [UIScreen mainScreen].bounds.size.width;
CGFloat heigth = [UIScreen mainScreen].bounds.size.height;

//创建UIView作为标签条

UIView * tabView = [[UIView alloc] initWithFrame:CGRectMake(0, heigth - 44, width, 44)];

tabView.backgroundColor = [UIColor orangeColor];
tabView.tag = 200;

//添加背景图
UIImageView * backImage = [[UIImageView alloc] initWithFrame:tabView.frame];

backImage.image = [UIImage imageNamed:@"naviback_n"];
[tabView addSubview:backImage];


NSArray * titleArr = @[@"I",@"M",@"P",@"Q",@"V"];

for (int i = 0; i < 5; i++) {

    UIButton * btn = [UIButton buttonWithType:UIButtonTypeCustom];
    btn.frame = CGRectMake(i * width/5.0, 0, width/5, 44);
    //未选中状态
    NSString * norName =[NSString stringWithFormat:@"btn%@-n",titleArr[i]];

    [btn setBackgroundImage:[UIImage imageNamed:norName] forState:UIControlStateNormal];
    //选中状态图片
    NSString * selName = [NSString stringWithFormat:@"btn%@-h",titleArr[i]];
    [btn setBackgroundImage:[UIImage imageNamed:selName] forState:UIControlStateSelected];
    btn.tag= 100+i;

    if (btn.tag == 100) {
        btn.selected = YES;
    }

    [btn addTarget:self action:@selector(changeState:) forControlEvents:UIControlEventTouchUpInside];
    [tabView addSubview:btn];

}

//添加下划线
UIImageView * lineImage = [[UIImageView alloc] initWithFrame:CGRectMake(0, 43, width/5, 2)];
lineImage.backgroundColor = [UIColor whiteColor];
lineImage.tag = 99;
[tabView addSubview:lineImage];

[self.view addSubview:tabView];

}

-(void)changeState:(UIButton *)btn{

// for (int i = 100; i< 105; i++){
// UIButton * btn1 = (id)[self.view viewWithTag:i];
// btn1.selected = NO;
// }

// static int value = 100;
// UIButton * btn1 = (id)[self.view viewWithTag:value];
// btn1.selected = NO;
// btn.selected = YES;
// value = btn.tag;
btn.selected = YES;

//tabBar.subviews所有的子视图
UIView * views = [self.view viewWithTag:200];
for (UIView * view in views.subviews) {
    if ([view isKindOfClass:[UIButton class]]) {
        //强转 只会改变变量类型不能改变对象类型
        UIButton * subBtn = (UIButton *)view;
        if (subBtn != btn) {
            subBtn.selected = NO;
        }
    }
}
//切换界面
self.selectedIndex = btn.tag-100;
//下划线移动

UIImageView * line = (id)[views viewWithTag:99];
[UIView animateWithDuration:0.5 animations:^{

    line.center = CGPointMake(btn.center.x, 43);

}];

}

协议使用

//第一个参数tabBarController 第二参数：是当前选中的界面
点击某个页面会触发这个方法 并且将点击的页面传入 是否可以被选择
- (BOOL)tabBarController:(UITabBarController )tabBarController shouldSelectViewController:(UIViewController )viewController{

NSUInteger num = [tabBarController.viewControllers indexOfObject:viewController];

if (num == 1) {
    return NO;
}

return YES;

}

• (void)tabBarController:(UITabBarController )tabBarController didSelectViewController:(UIViewController )viewController{
  //点击每个界面会调用这个方法
  }