UINavigationController基本使用

写了很长的NavigationController介绍，结果被cnblog吞了，没存档，算了，简单粗暴，直接上如何使用。

　　1.创建3个Controller，继承自UIViewController

在AppDelegate.h中

//
//  AppDelegate.m
//  UINavigationController
//
//  Created by lcd on 15/9/11.
//  Copyright (c) 2015年 lcd. All rights reserved.
//

#import "AppDelegate.h"
#import "FirstViewController.h"
#import "SecondViewController.h"
#import "ThirdViewController.h"

@interface AppDelegate ()

@end

@implementation AppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {

FirstViewController *firstViewController = [[FirstViewController alloc] init];

firstViewController.view.backgroundColor = [UIColor redColor];

SecondViewController *secondViewController = [[SecondViewController alloc] init];

secondViewController.view.backgroundColor = [UIColor whiteColor];

ThirdViewController *thirdViewController = [[ThirdViewController alloc] init];

　　 thirdViewController.view.backgroundColor = [UIColor cyanColor];

//创建导航控制器
    UINavigationController *navigation = [[UINavigationController alloc] init];

    return YES;
}

2.使用NavigationController有多种方式

//第一种：将需要NavigationController 管理的视图添加进NavigationController 的子视图数组中
    UINavigationController *navigation = [[UINavigationController alloc] init];
    navigation.viewControllers = @[firstViewController,secondViewController,thirdViewController];

//第二种：逐个添加子控制器
    [navigation addChildViewController:firstViewController];
    [navigation addChildViewController:secondViewController];
    [navigation addChildViewController:thirdViewController];

//第三种：初始化NavigationController时添加自控制器
    UINavigationController *navigation = [[UINavigationController alloc] initWithRootViewController:firstViewController];

3.添加子控制器后，将navigation设置为窗口的根控制器

self.window.rootViewController = navigation;

这样运行，显示的是第三个ViewController,这是因为，NavigationController是以栈的方式管理子视图，如图：

先添加的视图被放在了栈底，显示在我们面前的是栈顶视图。点击back会把栈顶视图弹出，即为出栈（pop）操作。

NavigationController以 push（入栈）和pop（出栈）管理子视图。

4. NavigationController 结构

4.1导航栏

被NavigationController管理的视图公用一个导航栏，导航栏显示内容由栈顶控制器决定

在ThirdViewController.m中

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    self.navigationItem.title = @"我是第三个控制器";
}

左上角返回键文字（Back） 由上一个控制器控制

在SecondViewController.m中

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    self.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"返回第二个界面" style:nil target:nil action:nil];
}

运行结果如下图：

4.2 在导航栏添加按钮

UIBarButtonItem *button1 = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemTrash target:nil action:nil];

UIBarButtonItem *button2 = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemCompose target:nil action:nil];

self.navigationItem.rightBarButtonItems = @[button1, button2];

修改右按钮格式

self.navigationItem.titleView = [UIButton buttonWithType:UIButtonTypeContactAdd];
    self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemTrash target:nil action:nil];
//左按钮同理

隐藏back按钮

[self.navigationItem setHidesBackButton:YES];

4.3 设置导航条样式

[self.navigationController.navigationBar setBarStyle:UIBarStyleDefault];

//样式枚举值如下：

typedef NS_ENUM(NSInteger, UIBarStyle) {

UIBarStyleDefault          = 0,

UIBarStyleBlack            = 1,

UIBarStyleBlackOpaque      = 1, // Deprecated. Use UIBarStyleBlack

UIBarStyleBlackTranslucent = 2, // Deprecated. Use UIBarStyleBlack and set the translucent property to YES

};

设置导航栏图片

[self.navigationController.navigationBar

setBackgroundImage:[UIImage imageNamed:@"图片名称"] forBarMetrics:UIBarMetricsDefault];

4.4 其他属性

//设置导航条颜色
    self.navigationController.navigationBar.barTintColor = [UIColor orangeColor];
    //关闭导航条毛玻璃效果
//    self.navigationController.navigationBar.translucent = NO;
    //隐藏导航条
//    self.navigationController.navigationBarHidden = YES;
    //设置导航条内容的颜色
    self.navigationController.navigationBar.tintColor = [UIColor whiteColor];
    //导航条背景图片
    [self.navigationController.navigationBar setBackgroundImage:[UIImage imageNamed:@"pic"] forBarMetrics:UIBarMetricsDefault];

titleTextAttributes

//这是UINavigationBar的一个属性，通过它你可以设置title部分的字体，这个属性定义如下
@property(nonatomic,copy) NSDictionary *titleTextAttributes __OSX_AVAILABLE_STARTING(__MAC_NA,__IPHONE_5_0) UI_APPEARANCE_SELECTOR;
//设置title的字体颜色为黄色
NSDictionary *dict = [NSDictionary dictionaryWithObject:[UIColor yellowColor] forKey:UITextAttributeTextColor];
firstViewController.navigationController.navigationBar.titleTextAttributes = dict;

5.界面跳转

从FirstViewController跳转到SceondViewController

在FirstViewController.m中，添加button，并在button事件中添加如下代码：

 SecondViewController *secondViewController = [[SecondViewController alloc] init];
 [self.navigationController pushViewController:secondViewController animated:YES];

从SceondViewController返回FirstViewController：

[self.navigationController popViewControllerAnimated:YES];

注意:从后一个界面跳转回前一个界面，一定要用popViewController，千万不要alloc一个FirstViewController，push到FirstViewController

[self.navigationController popToRootViewControllerAnimated:YES];//这个方法可以跳转回第一个界面