@implementation XMGTabBarController

- (void)viewDidLoad {
  [super viewDidLoad];
  
  //添加4個item bar
  UITableViewController *vc0 = [[UITableViewController alloc] init];
  vc0.view.backgroundColor = [UIColor redColor];
  vc0.tabBarItem.title = @"精華";
  vc0.tabBarItem.image = [UIImage imageNamed:@"tabBar_essence_icon"];
  vc0.tabBarItem.selectedImage = [UIImage imageNamed:@"tabBar_essence_click_icon"];
  [self addChildViewController:vc0];
  
  UIViewController *vc1 = [[UIViewController alloc] init];
  vc1.view.backgroundColor = [UIColor blueColor];
  vc1.tabBarItem.title = @"新帖";
  vc1.tabBarItem.image = [UIImage imageNamed:@"tabBar_new_icon"];
  vc1.tabBarItem.selectedImage = [UIImage imageNamed:@"tabBar_new_click_icon"];
  [self addChildViewController:vc1];
  
  UITableViewController *vc2 = [[UITableViewController alloc] init];
  vc2.view.backgroundColor = [UIColor greenColor];
  vc2.tabBarItem.title = @"關(guān)注";
  vc2.tabBarItem.image = [UIImage imageNamed:@"tabBar_friendTrends_icon"];
  vc2.tabBarItem.selectedImage = [UIImage imageNamed:@"tabBar_friendTrends_click_icon"];
  [self addChildViewController:vc2];
  
  UIViewController *vc3 = [[UIViewController alloc] init];
  vc3.view.backgroundColor = [UIColor grayColor];
  vc3.tabBarItem.title = @"我";
  vc3.tabBarItem.image = [UIImage imageNamed:@"tabBar_me_icon"];
  vc3.tabBarItem.selectedImage = [UIImage imageNamed:@"tabBar_me_click_icon"];
  [self addChildViewController:vc3];

   //下面的方法也是可以的，推薦使用下面的方法
//  [self addChildViewController:@[vc0,vc1,vc2,vc3]];
  
}

@implementation XMGTabBarController

- (void)viewDidLoad {
  [super viewDidLoad];
  
  /**** 添加子控制器 ****/
  [self setupOneChildViewController:[[UITableViewController alloc] init] title:@"精華" image:@"tabBar_essence_icon" selectedImage:@"tabBar_essence_click_icon"];
  [self setupOneChildViewController:[[UITableViewController alloc] init] title:@"新帖" image:@"tabBar_new_icon" selectedImage:@"tabBar_new_click_icon"];
  [self setupOneChildViewController:[[UIViewController alloc] init] title:@"關(guān)注" image:@"tabBar_friendTrends_icon" selectedImage:@"tabBar_friendTrends_click_icon"];
  [self setupOneChildViewController:[[UITableViewController alloc] init] title:@"我" image:@"tabBar_me_icon" selectedImage:@"tabBar_me_click_icon"];
}

/**
 * 初始化一個子控制器
 *
 * @param vc      子控制器
 * @param title     標(biāo)題
 * @param image     圖標(biāo)
 * @param selectedImage 選中的圖標(biāo)
 */
- (void)setupOneChildViewController:(UIViewController *)vc title:(NSString *)title image:(NSString *)image selectedImage:(NSString *)selectedImage
{
  vc.view.backgroundColor = [UIColor redColor];
  vc.tabBarItem.title = title;
  vc.tabBarItem.image = [UIImage imageNamed:image];
  vc.tabBarItem.selectedImage = [UIImage imageNamed:selectedImage];
  [self addChildViewController:vc];
}

@end

vc.tabBarItem.selectedImage = image;
UIButton *btn = [UIButton buttonWithType:UIButtonTypeSystem];
[btn setImage:image forState:UIControlStateNormal];

// 加載圖片
UIImage *tempImage = [UIImage imageNamed:@"tabBar_essence_click_icon"];
// 產(chǎn)生一張不會進(jìn)行自動渲染的圖片
UIImage *selectedImage = [tempImage imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];
vc.tabBarItem.selectedImage = selectedImage;

// 普通狀態(tài)下的文字屬性
NSMutableDictionary *normalAttrs = [NSMutableDictionary dictionary];
normalAttrs[NSFontAttributeName] = [UIFont systemFontOfSize:14];
normalAttrs[NSForegroundColorAttributeName] = [UIColor grayColor];
[vc.tabBarItem setTitleTextAttributes:normalAttrs forState:UIControlStateNormal];

// 選中狀態(tài)下的文字屬性
NSMutableDictionary *selectedAttrs = [NSMutableDictionary dictionary];
selectedAttrs[NSForegroundColorAttributeName] = [UIColor darkGrayColor];
[vc.tabBarItem setTitleTextAttributes:selectedAttrs forState:UIControlStateSelected];

// 字典中用到的key
1.iOS7之前(在UIStringDrawing.h中可以找到)
- 比如UITextAttributeFont\UITextAttributeTextColor
- 規(guī)律:UITextAttributeXXX
2.iOS7開始(在NSAttributedString.h中可以找到)
- 比如NSFontAttributeName\NSForegroundColorAttributeName
- 規(guī)律:NSXXXAttributeName

/**** 設(shè)置所有UITabBarItem的文字屬性 ****/
UITabBarItem *item = [UITabBarItem appearance];
// 普通狀態(tài)下的文字屬性
NSMutableDictionary *normalAttrs = [NSMutableDictionary dictionary];
normalAttrs[NSFontAttributeName] = [UIFont systemFontOfSize:14];
normalAttrs[NSForegroundColorAttributeName] = [UIColor grayColor];
[item setTitleTextAttributes:normalAttrs forState:UIControlStateNormal];
// 選中狀態(tài)下的文字屬性
NSMutableDictionary *selectedAttrs = [NSMutableDictionary dictionary];
selectedAttrs[NSForegroundColorAttributeName] = [UIColor darkGrayColor];
[item setTitleTextAttributes:normalAttrs forState:UIControlStateSelected];

//獲取全局的tabBarItem外觀標(biāo)識
UITabBarItem *item = [UITabBarItem appearance];

//獲取當(dāng)前這個類下面的所有tabBarItem
UITabBarItem *item = [UITabBarItem appearanceWhenContainedIn:self, nil]

#ifndef PrefixHeader_pch
#define PrefixHeader_pch
/*** 如果希望某些內(nèi)容能拷貝到任何源代碼文件(OC\C\C++等), 那么就不要寫在#ifdef __OBJC__和#endif之間 ***/
/***** 在#ifdef __OBJC__和#endif之間的內(nèi)容, 只會拷貝到OC源代碼文件中, 不會拷貝到其他語言的源代碼文件中 *****/
#ifdef __OBJC__
#endif
/***** 在#ifdef __OBJC__和#endif之間的內(nèi)容, 只會拷貝到OC源代碼文件中, 不會拷貝到其他語言的源代碼文件中 *****/
#endif