---恢复内容结束---

未完待续,先把代码上传到文件中去...

 代理属性用weak修饰

block属性用copy修饰

为什么???

还有block的三种写法

1.typedef

2.@property (nonatomic,copy)dispatch_block_t listBlock;

3.直接写

还有:代理,通知,block这三种传递数据方法的总结:

 

 

 

 

 

 

 

1.UITabBarController和UINavigationController的常用属性总结:

 

UINavigationController属性:

1.self.title 和self.navigationItem.title以及self.tabBarItem.title的区别

只要设置self.title,那么self.navigationItem.title和self.tabBarItem.title值不管设置与否都和self.title一致

所以,一般情况下不要直接设置self.title,需要navigationItem.title就设置navigationItem.title,需要tabBarItem.title就设置tabBarItem.title

2.如上图:navigationItem可以设置:title,titleView,left/right barButtonItem,backBarButtonItem

　　　　navigationBar可以设置:tintColor,transluCent

注意:渲染颜色只能用:

vc1.navigationController.navigationBar.barTintColor = [UIColor redColor];

不能写成:

[vc1.navigationController.navigationBar setTintColor:[UIColor redColor]];

因为这种设置不上去

还要注意一点经常很容易犯的错误:见代码红色部分

////  AppDelegate.m//  nav练习第二波////  Created by 曹魏 on 2016/11/30.//  Copyright © 2016年 itcast. All rights reserved.//#import "AppDelegate.h"#import "FirstTableViewController.h"@interface AppDelegate ()@end@implementation AppDelegate- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    //1.实例化window    self.window = [[UIWindow alloc]initWithFrame:[UIScreen mainScreen].bounds];    //2.设置window的背景颜色    self.window.backgroundColor = [UIColor whiteColor];    //3.实例化一个导航控制器    UINavigationController *nav = [[UINavigationController alloc]init];    //4.实例化一个tabbleView控制器    FirstTableViewController *first = [[FirstTableViewController alloc]init];    //5.设置tabbleView的背景颜色    first.tableView.backgroundColor = [UIColor blueColor]; //写在这儿是不显示的//    [tabbleVC.navigationController.navigationBar setTranslucent:NO];    //6.管理子控制器    nav.viewControllers = @[first];    //这两行代码的位置要注意,一定要写在第6步下面,如果写在上面是无法显示的,因为,我必须先管理这个控制器再设置navigationBar的一些属性    first.navigationController.navigationBar.barTintColor = [UIColor redColor];    [first.navigationController.navigationBar setTranslucent:NO];//千万不要设置navigationController的对象nav上,因为是无效的    //7.设置window的根控制器    self.window.rootViewController = nav;    //8.使window成为主窗口并可见    [self.window makeKeyAndVisible];            return YES;}

3.基本属性设置如下代码所示:

////  AppDelegate.m//  UINavigationController小结////  Created by 曹魏 on 2016/11/30.//  Copyright © 2016年 itcast. All rights reserved.//#import "AppDelegate.h"@interface AppDelegate ()@end@implementation AppDelegate- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    //1.实例化一个window    self.window = [[UIWindow alloc]initWithFrame:[UIScreen mainScreen].bounds];    //2.设置window的背景颜色    self.window.backgroundColor = [UIColor whiteColor];    //3.实例化一个导航控制器    UINavigationController *nav = [[UINavigationController alloc]init];        //4.实例化一个控制器    UITableViewController *vc1 = [[UITableViewController alloc]init];    vc1.view.backgroundColor = [UIColor grayColor];    //4.1设置title    vc1.navigationItem.title = @"隔壁老王";//    vc1.title = @"主界面";//    4.2设置titleview(会覆盖title)    UIImageView *imageView = [[UIImageView alloc]initWithFrame:CGRectMake(0, 0, 60, 35)];    imageView.image = [UIImage imageNamed:@"navigationbar_friendsearch"];            vc1.navigationItem.titleView = imageView;    //4.3设置返回按钮    vc1.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc]initWithTitle:@"返回" style:UIBarButtonItemStylePlain target:nil action:nil];    //4.4添加导航栏左边的按钮    vc1.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:nil action:nil];    //4.5添加导航栏右边的按钮    vc1.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemSave target:nil action:nil];        //    [vc1.navigationController.navigationBar setBarStyle:UIBarStyleBlack];            UITableViewController *vc2 = [[UITableViewController alloc]init];    vc2.view.backgroundColor = [UIColor purpleColor];    //设置title    vc2.navigationItem.title = @"天龙八部";    //5.管理该控制器    nav.viewControllers = @[vc1,vc2];        //4.6设置渲染颜色//    [vc1.navigationController.navigationBar setTintColor:[UIColor redColor]];    vc1.navigationController.navigationBar.barTintColor = [UIColor redColor];    [vc1.navigationController.navigationBar setTranslucent:NO];//    [vc1.navigationController.navigationBar setBarStyle:UIBarStyleBlack];    //6.设置window的根控制器    self.window.rootViewController = nav;    //7.使window成为主窗口并可见    [self.window makeKeyAndVisible];                    return YES;}@end

UITabBarController的基本属性:

代码没有进行封装,但相对很完整,看效果图

////  AppDelegate.m//  tabbarController的小练习////  Created by 曹魏 on 2016/11/30.//  Copyright © 2016年 itcast. All rights reserved.//#import "AppDelegate.h"@interface AppDelegate ()@end@implementation AppDelegate- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    //1.实例化window    self.window = [[UIWindow alloc]initWithFrame:[UIScreen mainScreen].bounds];    //2.设置window的背景颜色    self.window.backgroundColor = [UIColor whiteColor];    //3.实例化tabbar控制器    UITabBarController *tab = [[UITabBarController alloc]init];    //4.实例化taberviewController        UITableViewController *first = [[UITableViewController alloc]init];    first.tableView.backgroundColor = [UIColor purpleColor];    //设置第一个控制器的属性    first.tabBarItem.title = @"微信";    //设置title文字颜色 //设置title文字颜色这个要注意,这个方法不好记     [first.tabBarItem setTitleTextAttributes:@{NSForegroundColorAttributeName:[UIColor colorWithRed:31/255.0 green:185/255.0 blue:34/255.0 alpha:1.0]} forState:UIControlStateSelected];    //设置图片    first.tabBarItem.image = [UIImage imageNamed:@"tabbar_mainframe"];    //设置选中状态下的图片    first.tabBarItem.selectedImage = [[UIImage imageNamed:@"tabbar_mainframeHL"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];

//设置信息

      first.tabBarItem.badgeValue = @"10";

UITableViewController *second = [[UITableViewController alloc]init];    second.tableView.backgroundColor = [UIColor redColor];    second.tabBarItem.title = @"通讯录";    //设置图片    second.tabBarItem.image = [UIImage imageNamed:@"tabbar_contacts"];    //设置选中状态下的图片    second.tabBarItem.selectedImage = [[UIImage imageNamed:@"tabbar_contactsHL"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];    //设置title文字颜色    [second.tabBarItem setTitleTextAttributes:@{NSForegroundColorAttributeName:[UIColor colorWithRed:31/255.0 green:185/255.0 blue:34/255.0 alpha:1.0]} forState:UIControlStateSelected];            UITableViewController *third = [[UITableViewController alloc]init];    third.tableView.backgroundColor = [UIColor grayColor];    third.tabBarItem.title = @"发现";    //设置图片    third.tabBarItem.image = [UIImage imageNamed:@"tabbar_discover"];    //设置选中状态下的图片    third.tabBarItem.selectedImage = [[UIImage imageNamed:@"tabbar_discoverHL"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];    //设置title文字颜色    [third.tabBarItem setTitleTextAttributes:@{NSForegroundColorAttributeName:[UIColor colorWithRed:31/255.0 green:185/255.0 blue:34/255.0 alpha:1.0]} forState:UIControlStateSelected];        UITableViewController *four = [[UITableViewController alloc]init];    four.tableView.backgroundColor = [UIColor yellowColor];    four.tabBarItem.title = @"我";    //设置title文字颜色    [four.tabBarItem setTitleTextAttributes:@{NSForegroundColorAttributeName:[UIColor colorWithRed:31/255.0 green:185/255.0 blue:34/255.0 alpha:1.0]} forState:UIControlStateSelected];        //设置图片    four.tabBarItem.image = [UIImage imageNamed:@"tabbar_me"];    //设置选中状态下的图片    four.tabBarItem.selectedImage = [[UIImage imageNamed:@"tabbar_meHL"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];            //5.管理控制器    tab.viewControllers = @[first,second,third,four];    //6.设置window的根控制器    self.window.rootViewController = tab;    //7.使window成为主窗口并可见    [self.window makeKeyAndVisible];    return YES;}@end

       

2.UITabBarController和UINavigationController的区别总结:

TabBarController 在进行界面切换, 没有看到的控制器, 没有被销毁

NavigationController控制器在pop操作后会被销毁

StoryBoard中跳转界面时二者的区别:

NavigationController跳转的时候选择的是用push

TabBarController跳转的时候选择的是view controllers(数组,有序)

 3.键盘弹出的通知小结:

////  ViewController.m//  键盘响应小练习第二种////  Created by 曹魏 on 2016/12/2.//  Copyright © 2016年 itcast. All rights reserved.//#import "ViewController.h"@interface ViewController ()
     
      @property (weak, nonatomic) IBOutlet UITextField *nameField;@property (weak, nonatomic) IBOutlet UITextField *phoneField;@property (weak, nonatomic) IBOutlet UITextField *addressField;@property (nonatomic,assign) CGFloat maxY;@end@implementation ViewController- (void)viewDidLoad {    [super viewDidLoad];    //取消自动联想功能    _nameField.autocorrectionType = UITextAutocorrectionTypeNo;    _phoneField.autocorrectionType = UITextAutocorrectionTypeNo;    _addressField.autocorrectionType = UITextAutocorrectionTypeNo;    //设置代理    _nameField.delegate = self;    _phoneField.delegate = self;    _addressField.delegate = self;        //当我点击textfield的时候,系统会发出一些通知,我通过添加控制器为监听者来监听各种通知    //从而实现view的上移    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(changeKeyboard:) name:UIKeyboardWillChangeFrameNotification object:nil];        }- (void)changeKeyboard:(NSNotification *)notification{        NSLog(@"键盘事件 %@",notification);    //    {name = UIKeyboardWillShowNotification; userInfo = {    //        UIKeyboardAnimationCurveUserInfoKey = 7;   执行动画的方式,执行动画的样式    //        UIKeyboardAnimationDurationUserInfoKey = "0.25";  动画执行的时间    //        UIKeyboardBoundsUserInfoKey = "NSRect: {
    {0, 0}, {375, 258}}"; 键盘的bounds    //        UIKeyboardCenterBeginUserInfoKey = "NSPoint: {187.5, 796}"; 键盘开始(为显示)的中心点    //        UIKeyboardCenterEndUserInfoKey = "NSPoint: {187.5, 538}";  键盘结束(已经显示)的中心店    //        UIKeyboardFrameBeginUserInfoKey = "NSRect: {
    {0, 667}, {375, 258}}"; 键盘未显示时的frame    //        UIKeyboardFrameEndUserInfoKey = "NSRect: {
    {0, 409}, {375, 258}}"; 键盘结束时的frame    //        UIKeyboardIsLocalUserInfoKey = 1; 是否是当前弹出的键盘    //    }        NSDictionary *userInfo = notification.userInfo;    //动画    CGFloat duration = [userInfo[@"UIKeyboardAnimationDurationUserInfoKey"] floatValue];    //获取键盘弹出后的frame    CGFloat keyBoardY = [userInfo[@"UIKeyboardFrameEndUserInfoKey"] CGRectValue].origin.y;    [UIView animateWithDuration:duration animations:^{                if (_maxY > keyBoardY) {            CGFloat move = keyBoardY - _maxY - 10;            self.view.transform = CGAffineTransformMakeTranslation(0, move);        }else{            self.view.transform = CGAffineTransformIdentity;        }            }];    }#pragma mark -- 实现代理方法- (void)textFieldDidBeginEditing:(UITextField *)textField{    //获取textfield的frame最大y值    _maxY = CGRectGetMaxY(textField.frame);    }- (void)touchesBegan:(NSSet
      
        *)touches withEvent:(UIEvent *)event{    //取消第一响应者    [self.view endEditing:YES];}@end
      
     

小结:1:当我点击textField的时候,如果是在storyBoard中添加控件并连线的方式的话,系统会自动在我点击的时候,让该textField成为第一响应者(效果也就是弹出键盘)

当我用纯代码写的时候,我点击textField是不会自动弹出键盘的,这个时候必须要加一句代码:[self.textField becomeFirstResponder];才可以.

2:当我点击textField的时候,系统会发出相应的通知,详细见下方,可根据相应的通知采取相应的办法去完成键盘的变化

UIKIT_EXTERN NSNotificationName const UIWindowDidBecomeVisibleNotification; // nilUIKIT_EXTERN NSNotificationName const UIWindowDidBecomeHiddenNotification;  // nilUIKIT_EXTERN NSNotificationName const UIWindowDidBecomeKeyNotification;     // nilUIKIT_EXTERN NSNotificationName const UIWindowDidResignKeyNotification;     // nil// Each notification includes a nil object and a userInfo dictionary containing the// begining and ending keyboard frame in screen coordinates. Use the various UIView and// UIWindow convertRect facilities to get the frame in the desired coordinate system.// Animation key/value pairs are only available for the "will" family of notification.UIKIT_EXTERN NSNotificationName const UIKeyboardWillShowNotification __TVOS_PROHIBITED;UIKIT_EXTERN NSNotificationName const UIKeyboardDidShowNotification __TVOS_PROHIBITED;UIKIT_EXTERN NSNotificationName const UIKeyboardWillHideNotification __TVOS_PROHIBITED;UIKIT_EXTERN NSNotificationName const UIKeyboardDidHideNotification __TVOS_PROHIBITED;UIKIT_EXTERN NSString *const UIKeyboardFrameBeginUserInfoKey        NS_AVAILABLE_IOS(3_2) __TVOS_PROHIBITED; // NSValue of CGRectUIKIT_EXTERN NSString *const UIKeyboardFrameEndUserInfoKey          NS_AVAILABLE_IOS(3_2) __TVOS_PROHIBITED; // NSValue of CGRectUIKIT_EXTERN NSString *const UIKeyboardAnimationDurationUserInfoKey NS_AVAILABLE_IOS(3_0) __TVOS_PROHIBITED; // NSNumber of doubleUIKIT_EXTERN NSString *const UIKeyboardAnimationCurveUserInfoKey    NS_AVAILABLE_IOS(3_0) __TVOS_PROHIBITED; // NSNumber of NSUInteger (UIViewAnimationCurve)UIKIT_EXTERN NSString *const UIKeyboardIsLocalUserInfoKey           NS_AVAILABLE_IOS(9_0) __TVOS_PROHIBITED; // NSNumber of BOOL// Like the standard keyboard notifications above, these additional notifications include// a nil object and begin/end frames of the keyboard in screen coordinates in the userInfo dictionary.UIKIT_EXTERN NSNotificationName const UIKeyboardWillChangeFrameNotification  NS_AVAILABLE_IOS(5_0) __TVOS_PROHIBITED;UIKIT_EXTERN NSNotificationName const UIKeyboardDidChangeFrameNotification   NS_AVAILABLE_IOS(5_0) __TVOS_PROHIBITED;

上述只是第一种思路去让键盘弹出发出通知达到输入框上移的效果,这种思路比较有针对性,就是经过了一个判断:当键盘没有盖住输入框时,不上移,盖住了才上移,下面还有一种方法是无论盖不盖住都上移固定的距离,代码如下:

////  ViewController.m//  键盘响应小练习////  Created by 曹魏 on 2016/12/1.//  Copyright © 2016年 itcast. All rights reserved.//#import "ViewController.h"@interface ViewController ()@property (weak, nonatomic) IBOutlet UITextField *birthdayField;@property (weak, nonatomic) IBOutlet UITextField *nameField;@property (weak, nonatomic) IBOutlet UITextField *addressField;@end@implementation ViewController- (void)viewDidLoad {    [super viewDidLoad];    //取消键盘的自动联想功能    self.birthdayField.autocorrectionType = UITextAutocorrectionTypeNo;    self.nameField.autocorrectionType = UITextAutocorrectionTypeNo;    self.addressField.autocorrectionType = UITextAutocorrectionTypeNo;    //键盘将要显示    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(changeKeyboard:) name:UIKeyboardWillShowNotification object:nil];    //键盘将要隐藏    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(changeKeyboard:) name:UIKeyboardWillHideNotification object:nil];}- (void)changeKeyboard:(NSNotification *)notification{    //获取额外信息    NSDictionary *userInfo = notification.userInfo;    //获取结束时的frame    CGRect endFrame = [userInfo[@"UIKeyboardFrameEndUserInfoKey"] CGRectValue];    //计算要移动的距离    CGFloat move = endFrame.origin.y - self.view.bounds.size.height;    //让界面跟着移动    self.view.transform = CGAffineTransformMakeTranslation(0, move);    }- (void)touchesBegan:(NSSet
     
       *)touches withEvent:(UIEvent *)event{    [self.view endEditing:YES];}@end
     

说实话:这个方法的心机好重,很绕弯子!!!!

小知识点:

@property 和_实例变量的区别:

@property多了set 和get 方法的声明和实现

 

 

4.用户偏好设置的封装 

采用分类的方式对NSUserDefaults进行封装,很简单的,就是在分类中提供一些接口,接口做成类方法,供NSUserDefaults使用,主要注意枚举的写法.

////  NSUserDefaults+WP.h//  01-通讯录////  Created by apple on 16/8/1.//  Copyright © 2016年 itcast. All rights reserved.//#import 
     
      /** 分类的主要目的: 帮我们保存和获取 存储的value */// 定义 枚举, 来分辨 是那种开关typedef NS_ENUM(NSInteger, SwitchType) {    SwitchTypeRecord,    SwitchTypeAuto};@interface NSUserDefaults (WP)/** 返回值   传递的参数  key 值, 保存的值 */// 保存 按钮状态+ (void)saveBoolValue:(BOOL)value forType:(SwitchType)type;// 获取按钮状态+ (BOOL)getBoolVlaueWithType:(SwitchType)type;@end
     

////  NSUserDefaults+WP.m//  01-通讯录////  Created by apple on 16/8/1.//  Copyright © 2016年 itcast. All rights reserved.//#import "NSUserDefaults+WP.h"#define kAutoSwitch @"autoSwitch"#define kRecordSwitch @"recordSwitch"@implementation NSUserDefaults (WP)// 保存 按钮状态+ (void)saveBoolValue:(BOOL)value forType:(SwitchType)type {        // 根据type的类型, 来决定key值    NSString *key = type == SwitchTypeAuto ? kAutoSwitch : kRecordSwitch;        [[NSUserDefaults standardUserDefaults] setBool:value forKey:key];    // 强制写入一次    [[NSUserDefaults standardUserDefaults] synchronize];}// 获取按钮状态+ (BOOL)getBoolVlaueWithType:(SwitchType)type {    // 根据type的类型, 来决定key值    NSString *key = type == SwitchTypeAuto ? kAutoSwitch : kRecordSwitch;            return [[NSUserDefaults standardUserDefaults] boolForKey:key];    }+ (void)resetAllValues {        [[NSUserDefaults standardUserDefaults] setBool:NO forKey:kRecordSwitch];    [[NSUserDefaults standardUserDefaults] setBool:NO forKey:kAutoSwitch];    //    [[NSUserDefaults standardUserDefaults] setObject:@"" forKey:kUserName];//    [[NSUserDefaults standardUserDefaults] setObject:@"" forKey:kPassword];}@end

 

 

 

 

5.修改分割线缩进:

解释:就是将tableview的线距离屏幕左右为0 ,达到没有间距的效果.

所以,可以把这个当成万能代码直接拷贝!!!

 

/** 修改分割线缩进为0 */- (void)viewDidLayoutSubviews{    if ([self.tableView respondsToSelector:@selector(setSeparatorInset:)]) {        [self.tableView setSeparatorInset:UIEdgeInsetsMake(0, 0, 0, 0)];    }        if ([self.tableView respondsToSelector:@selector(setLayoutMargins:)]) {        [self.tableView setLayoutMargins:UIEdgeInsetsMake(0, 0, 0, 0)];    }}- (void)tableView:(UITableView*)tableView willDisplayCell:(UITableViewCell*)cell forRowAtIndexPath:(NSIndexPath*)indexPath{    if ([cell respondsToSelector:@selector(setSeparatorInset:)]) {        [cell setSeparatorInset:UIEdgeInsetsZero];    }        if ([cell respondsToSelector:@selector(setLayoutMargins:)]) {        [cell setLayoutMargins:UIEdgeInsetsZero];    }}/** 修改分割线缩进为0 */

 6.模态控制器的使用:

 效果:由下往上弹出一个控制器,覆盖上一个控制器,但原控制器并没有消失

注意点:谁model(present) 谁dismiss

注意:模态控制器有个小问题:见红色部分

////  FirstViewController.m//  模态控制器的小练习////  Created by 曹魏 on 2016/12/4.//  Copyright © 2016年 itcast. All rights reserved.//#import "FirstViewController.h"#import "SecondViewController.h"@interface FirstViewController ()@end@implementation FirstViewController- (void)viewDidLoad {    [super viewDidLoad];    self.view.backgroundColor = [UIColor redColor];}#pragma mark -- 点击屏幕跳转界面- (void)touchesBegan:(NSSet
     
       *)touches withEvent:(UIEvent *)event{    SecondViewController *second = [[SecondViewController alloc]init]; //下面这个方法是模态时的样式选择,是个枚举,我想说的是枚举方法四中的
     

UIModalTransitionStylePartialCurl 翻转效果是很特殊的,当我选择这个效果样式时,模态到另一个控制器,再点击界面上任何一点是可以回去的,但别的样式方法不行.

//    second.modalTransitionStyle = UIModalTransitionStylePartialCurl;    /*          typedef NS_ENUM(NSInteger, UIModalTransitionStyle) {     UIModalTransitionStyleCoverVertical = 0,     UIModalTransitionStyleFlipHorizontal __TVOS_PROHIBITED,     UIModalTransitionStyleCrossDissolve,     UIModalTransitionStylePartialCurl NS_ENUM_AVAILABLE_IOS(3_2) __TVOS_PROHIBITED,     };          */    second.modalTransitionStyle = UIModalTransitionStylePartialCurl;        UINavigationController *nav = [[UINavigationController alloc]initWithRootViewController:second];        [self presentViewController:nav animated:YES completion:nil];}@end

 

 特别简单,模态控制器是可以同时管理UITabBarController和UINavigationController的,所以更简单了,从一个控制器模态到第二个控制器,第一个控制器失去响应,例如很多

弹窗就是这样的,下举个小小栗子说明一下:

#import "AppDelegate.h"#import "OneViewController.h"@interface AppDelegate ()@end@implementation AppDelegate- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    self.window = [[UIWindow alloc]initWithFrame:[UIScreen mainScreen].bounds];    OneViewController *one = [[OneViewController alloc]init];    self.window.rootViewController = one;                    [self.window makeKeyAndVisible];                    return YES;}

#import "OneViewController.h"#import "TwoViewController.h"@interface OneViewController ()@property (weak, nonatomic) IBOutlet UIButton *modal;@end@implementation OneViewController- (void)viewDidLoad {    [super viewDidLoad];}- (IBAction)didClickModal:(UIButton *)sender {    TwoViewController *two = [[TwoViewController alloc]init];    UINavigationController *nav = [[UINavigationController alloc]initWithRootViewController:two];    [self presentViewController:nav animated:YES completion:^{            }];    }

#import "TwoViewController.h"@interface TwoViewController ()@end@implementation TwoViewController- (void)viewDidLoad {    [super viewDidLoad];    self.title = @"第二个控制器";    self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc]initWithTitle:@"取消" style:UIBarButtonItemStylePlain target:self action:@selector(cancel)];    }- (void)cancel{#pragma mark -- 以下两种方式都可以进行dismiss操作,one-->nav是present操作过来(模态),self.navigationController dismiss属于理所应当,但其实其子控制器也可以执行操作达到同样的效果//    [self dismissViewControllerAnimated:YES completion:^{//        //    }];    [self.navigationController dismissViewControllerAnimated:YES completion:^{            }];}@end

很简单,注意一下红色字体即可.

 

 

 

 

 

 

 

 

 

iOS中dismissViewController实现多级模态跳转

当我要用到dismiss实现多级模态跳转的时候,即我想从present 顺序是:A->B->C,当我点击C 的时候直接回到A控制器,由于dismiss操作本质上是由上个发出present操作的控制器所发出的,即假设:B控制器采用dismiss方法回到A控制器,在B中我们通常会写:[self dismissViewControllerAnimated:YES completion:nil];这个方法,本质上这个方法的调用其实是A控制器,B中写这个方法会通知A控制器去执行,表面上是B执行,但本质上是A控制器去执行,

还有注意点:当我点击C控制器回到A控制器时肯定要用到block或者代理通知,

也就是说，其实在present多个视图控制器的时候，系统维护了一个栈，以我们现在这个情况为例，从栈底到栈顶依次是A->B->C。当栈中某个位置的视图控制器执行dismissViewController方法的时候，栈中所有在它之上的视图控制器都会被dismiss，不同的是，栈顶的视图控制器将会以动画方式被dismiss，而中间的视图控制器只是简单的remove掉

可以参考官方文档:http://m.blog.csdn.net/article/details?id=50950915