031实现仿iPhone的底部选项卡

效果如下：

ViewController.h

1 #import <UIKit/UIKit.h>
2
3 @interface ViewController : UITabBarController
4 @end

ViewController.m

 1 #import "ViewController.h"
 2 #import "SampleScene.h"
 3
 4 @interface ViewController ()
 5 - (void)layoutUI;
 6 @end
 7
 8 @implementation ViewController
 9
10 - (void)viewDidLoad {
11     [super viewDidLoad];
12
13     [self layoutUI];
14 }
15
16 - (void)didReceiveMemoryWarning {
17     [super didReceiveMemoryWarning];
18     // Dispose of any resources that can be recreated.
19 }
20
21 /**
22  *  加载的UI内容
23  */
24 - (void)layoutUI {
25     self.title = @"UITabBarController";
26     /*
27     id scene1 = [[SampleScene alloc] initWithSystemItem:UITabBarSystemItemMore badge:nil];
28     id scene2 = [[SampleScene alloc] initWithSystemItem:UITabBarSystemItemFavorites badge:nil];
29     id scene3 = [[SampleScene alloc] initWithSystemItem:UITabBarSystemItemFeatured badge:nil];
30     id scene4 = [[SampleScene alloc] initWithSystemItem:UITabBarSystemItemTopRated badge:nil];
31     id scene5 = [[SampleScene alloc] initWithSystemItem:UITabBarSystemItemRecents badge:nil];
32     id scene6 = [[SampleScene alloc] initWithSystemItem:UITabBarSystemItemContacts badge:nil];
33     id scene7 = [[SampleScene alloc] initWithSystemItem:UITabBarSystemItemHistory badge:nil];
34     */
35     id scene8 = [[SampleScene alloc] initWithSystemItem:UITabBarSystemItemBookmarks badge:nil];
36     id scene9 = [[SampleScene alloc] initWithSystemItem:UITabBarSystemItemSearch badge:nil];
37     id scene10 = [[SampleScene alloc] initWithSystemItem:UITabBarSystemItemDownloads badge:@"2"];
38     id scene11 = [[SampleScene alloc] initWithSystemItem:UITabBarSystemItemMostRecent badge:nil];
39     id scene12 = [[SampleScene alloc] initWithSystemItem:UITabBarSystemItemMostViewed badge:nil];
40
41     id scene13 = [[SampleScene alloc] initWithFileName:@"Smile.png" title:@"微 笑" badge:@"1"];
42     [self setViewControllers:@[scene10, scene11, scene12, scene13, scene8, scene9] animated:NO]; //self必须是继承UITabBarController，而不是UIViewController才可以调用setViewControllers方法；iOS8显示是4个tabBarItem
43     self.customizableViewControllers = @[scene10, scene11, scene12, scene13, scene8, scene9]; //没啥用
44
45     self.selectedIndex = 3; //默认值是0
46 }
47
48 @end

SampleScene.h

 1 #import <UIKit/UIKit.h>
 2
 3 @interface SampleScene : UIViewController
 4 @property (nonatomic, strong) UILabel *lblMessage;
 5 @property (nonatomic, assign) NSUInteger tabBarItemType;
 6
 7 - (id)initWithSystemItem:(UITabBarSystemItem)item badge:(NSString *)badge;
 8 - (id)initWithFileName:(NSString *)fileName title:(NSString *)title badge:(NSString *)badge;
 9
10 @end

SampleScene.m

 1 #import "SampleScene.h"
 2
 3 @interface SampleScene ()
 4 @end
 5
 6 @implementation SampleScene
 7
 8 - (void)viewDidLoad {
 9     [super viewDidLoad];
10     _lblMessage = [[UILabel alloc] initWithFrame:self.view.bounds];
11     _lblMessage.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
12     switch (_tabBarItemType) {
13         case 1:
14             _lblMessage.backgroundColor = [UIColor orangeColor];
15             break;
16         case 2:
17             _lblMessage.backgroundColor = [UIColor brownColor];
18             break;
19         case 3:
20             _lblMessage.backgroundColor = [UIColor cyanColor];
21             break;
22         default:
23             _lblMessage.backgroundColor = [UIColor lightGrayColor];
24             break;
25     }
26
27     [self.view addSubview:_lblMessage];
28
29     NSLog(@"viewDidLoad");
30 }
31
32 - (void)didReceiveMemoryWarning {
33     [super didReceiveMemoryWarning];
34     // Dispose of any resources that can be recreated.
35 }
36
37 /**
38  通过系统图标加载UITabBarItem
39  */
40 - (id)initWithSystemItem:(UITabBarSystemItem)item badge:(NSString *)badge {
41     if (self = [super init]) {
42         self.tabBarItem = [[UITabBarItem alloc] initWithTabBarSystemItem:item tag:0];
43         self.tabBarItem.badgeValue = badge;
44
45         if (item == UITabBarSystemItemMostRecent) {
46             _tabBarItemType = 1;
47         } else if (item == UITabBarSystemItemMostViewed) {
48             _tabBarItemType = 2;
49         }
50     }
51     NSLog(@"initWithSystemItem");
52     return self;
53 }
54
55 /**
56  通过自定义图标加载UITabBarItem
57  */
58 - (id)initWithFileName:(NSString *)fileName title:(NSString *)title badge:(NSString *)badge {
59     if (self = [super init]) {
60         UIImage *imgIcon = [UIImage imageNamed:fileName];
61         self.tabBarItem = [[UITabBarItem alloc] initWithTitle:title image:imgIcon tag:0];
62         self.tabBarItem.badgeValue = badge;
63
64         _tabBarItemType = 3;
65     }
66     return self;
67 }
68
69 @end