导航控制器和表视图(一)

        这两天在看导航控制器和表视图这一块，发现很苦逼，特别是XIB文件关联的时候，要不是关联不上，拉着没反应，要不是关联上了，结果苦逼的错了，造成内存泄露等问题，导致失败。但是这些失败也不是浪费时间的，从中还是能获得经验的；因为前面练习的时候一直坚持用代码编写，但是想着苹果公司开发出这么好的开发工具，如果不会去用，那岂不是更苦逼了，现在用的是有问题，但都是时间问题，如果能理解XIB的关联操作一定分享下心的。哎哎，也不抱怨了，开始介绍今天内容；

实现功能是：表视图每一行都有拓展图标，显示该行的详细内容。表视图上面是一个导航栏，导航栏上面有返回上一级按钮，然后就是来回的切换；先展示下所实现的效果图：

      

再说一下导航栏控制器，UINavigationController，主要用于分层的应用程序开发，管理视图的进入和退出，主要是通过栈来实现，如果不知道栈是什么建议还是在网上先了解一下栈的原理，此处用栈的内容不是太多；

实现步骤

 1.新建工程名为NavigationController ， File->New->Project ->single View Application -> next 

2.在新建一个文件控制器FirstLevelViewController，不生成XIB文件，继承UITableViewController

3.设置导航控制器

在NavViewContoller.h中声明一个导航控制器输出口，在NavViewContoller.h中添加@synthesize navigationController = _navigationController;

#import <UIKit/UIKit.h>@interface NavViewController : UIViewController@property(strong,nonatomic) IBOutlet UINavigationController *navigationController;@end

4.创建导航控制器，连接输出口navigationController，打开NavViewController.xib文件，拖动一个NavigationController，自动生成如图所示导航视图

   
5.关联输出口,选中navigationController

6.单击View Controller-RootViewcontroller，将底层类改为FirstLevelViewController，这样，在加载nib文件时候，当行控制器将于FirstLevelViewController一起实例化；NIB Name属性保持为空，不做更改

    

7.从开始文章截图上我们看到，第一级视图上，FirstLevel下面表视图单元格上左边有一个Image属性，我们可以创建一个UITableViewController子类，因为UITableViewController有UIImage属性，可以显示图片，而不是用UIImage属性直接添加每个子控制器中，然后子类化这个新类；

创建二级视图控制器，SecondLevelController，Subclass of 一栏选UITableViewController，然后添加UIImage属性

#import <UIKit/UIKit.h>@interface SecondLevelViewController : UITableViewController@property (strong,nonatomic) UIImage *rowImage;@end

在.m文件中添加 @synthesize rowImage = _rowImage;

8.实现FirstLevelViewController，

#import <UIKit/UIKit.h>@interface FirstLevelViewController : UIViewController                <UITableViewDelegate,UITableViewDataSource>@property(strong,nonatomic) NSArray *controllers;@end

- (void)viewDidLoad{    [super viewDidLoad];    UITableView *tableView =[[UITableView alloc] initWithFrame:CGRectMake(0, 0, 320, 416) style:UITableViewStylePlain];    tableView.delegate = self;    tableView.dataSource = self;    [self.view addSubview:tableView];        //    设置导航控制器标题，让用户知道当前所处位置    self.title = @"First Level";    NSMutableArray *array = [[NSMutableArray alloc]init];    self.controllers = array;  }

代理方法

#pragma mark -#pragma mark Table Data Soursen Methods-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{    return [self.controllers count];}-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{    static NSString *FirstLevelCell = @"FirstLevelCell";    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:FirstLevelCell];        if (cell == nil) {        cell= [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:FirstLevelCell];    }        NSUInteger row = [indexPath row];    SecondLevelViewController *controller = [self.controllers objectAtIndex:row];    cell.textLabel.text = controller.title;    cell.imageView.image = controller.rowImage;    cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;    return cell;}#pragma mark -#pragma mark Table View Delegate Methods-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{    NSUInteger row = [indexPath row];    SecondLevelViewController *nextController = [self.controllers objectAtIndex:row];    [self.navigationController pushViewController:nextController animated:YES];}

还需要添加头文件 #import "SecondLevelViewController.h"  以上完成应该是这样的

9.在新建一个控制器，DIsclosureViewController和DisclosureDetailViewController，第二个勾选生成XIB

#import <UIKit/UIKit.h>@interface DisclosureDetailViewController : UIViewController@property (strong,nonatomic) IBOutlet UILabel *label;@property (nonatomic,copy) NSString *message;@end在DisclosureDetailViewController.xib文件拖一个UILabel，用于显示文字，进行关联#import "DisclosureDetailViewController.h"@interface DisclosureDetailViewController ()@end

@implementation DisclosureDetailViewController@synthesize label = _label;@synthesize message =_message;- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil{    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];    if (self) {        // Custom initialization    }    return self;}- (void)viewDidLoad{    [super viewDidLoad];    // Do any additional setup after loading the view from its nib.}- (void)viewDidUnload{    [super viewDidUnload];        self.label=nil;    self.message = nil;}- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation{    return (interfaceOrientation == UIInterfaceOrientationPortrait);}-(void) viewWillAppear:(BOOL)animated{    self.label.text = self.message;    [super viewWillAppear:animated];}@end

11.为DIsclosureViewControoler填充代码

#import <UIKit/UIKit.h>#import "SecondLevelViewController.h"#import "DisclosureDetailViewController.h"@interface DIsclosureButtonController :SecondLevelViewController<UITableViewDataSource,UITableViewDelegate>@property (strong,nonatomic) NSArray *list;@property (strong,nonatomic) DisclosureDetailViewController * childController;@end

#import "DIsclosureButtonController.h"#import "NavAppDelegate.h"#import "DisclosureDetailViewController.h"@implementation DIsclosureButtonController@synthesize list =_list;@synthesize childController=_childController;-(void)viewDidLoad{    NSArray *array = [[NSArray alloc]initWithObjects:@"Toy Sooory",@"A Bug life",@"Toy Sooory2",@"Monsters,Inc",@"FInderDemo",@"The Incredibles",@"Cars",@"Ratatouille",@"WALL-E",@"Up",@"Toy SOOOry3",@"Brave",@"Down",@"cCao", nil];        self.list =array;        [super viewDidLoad];}-(void) viewDidUnload{    self.list=nil;    self.childController=nil;}#pragma  mark -#pragma mark Table Data Souce Methods-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{    return [self.list count];}-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{    static NSString *DisClosureButtonCellIdentfier= @"DisClosureButtonCellIdentier";    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:DisClosureButtonCellIdentfier];        if (cell == nil) {        cell= [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:DisClosureButtonCellIdentfier];    }        NSUInteger row = [indexPath row];    NSString *rowString = [self.list objectAtIndex:row];    cell.textLabel.text = rowString;    cell.accessoryType = UITableViewCellAccessoryDetailDisclosureButton;        return cell;}#pragma mark -#pragma mark Table Delegate Methods-(void) tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Hey,do you see the disclosure button?"                                                    message:@"if you are trying to drill down,touch that instaed"                                                   delegate:nil                                          cancelButtonTitle:@"wont't happed again"                                          otherButtonTitles: nil];    [alert show];}-(void) tableView:(UITableView *)tableView accessoryButtonTappedForRowWithIndexPath:(NSIndexPath *)indexPath{    if (self.childController == nil) {        self.childController = [[DisclosureDetailViewController alloc]initWithNibName:@"DisclosureDetailViewController" bundle:nil];    }    self.childController.title =@"DisClosure Button Pressed";    NSUInteger row = [indexPath row];    NSString *selectedMovie = [self.list objectAtIndex:row];        NSString *detailMessage = [[NSString alloc]initWithFormat:@"you pressed   the disclosure button for  %@",selectedMovie];        self.childController.message = detailMessage;    self.childController.title = selectedMovie;    [self.navigationController pushViewController:self.childController animated:YES];}@end

附上代码:http://download.csdn.net/detail/duxinfeng2010/4428970