//
//  AppDelegate.m
//  navigation的简单实用(纯代码)
//
//  Created by gxiangzi on 15/8/7.
//  Copyright (c) 2015年 itcast. All rights reserved.
//

#import "AppDelegate.h"
#import "GXNavController.h"

@interface AppDelegate ()

@end

@implementation AppDelegate

- (BOOL)application:(UIApplication*)application didFinishLaunchingWithOptions:(NSDictionary*)launchOptions
{
    self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
    // 创建一个导航控制器
    GXNavController* navc = [[GXNavController alloc] init];
    // 设置跟控制器为导航控制器
    self.window.rootViewController = navc;
    [self.window makeKeyAndVisible];
    return YES;
}

.....

#import <UIKit/UIKit.h>

@interface GXNavController : UINavigationController

@end

//
//  GXNavController.m
//  navigation的简单实用(纯代码)
//
//  Created by gxiangzi on 15/8/7.
//  Copyright (c) 2015年 itcast. All rights reserved.
//

#import "GXNavController.h"
#import "GXFirstController.h"

@interface GXNavController ()
@end

@implementation GXNavController

// 重写父类的init方法，设置跟控制器
- (instancetype)init
{
    GXFirstController* first = [[GXFirstController alloc] init];
    first.view.backgroundColor = [UIColor whiteColor];
    return [super initWithRootViewController:first];
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    // 第一个隐藏导航条
    self.navigationBar.hidden = YES;
}

// 重写导航控制器的push方法，设置返回按钮为back
- (void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated
{
    // 显示导航条
    self.navigationBar.hidden = NO;
    [super pushViewController:viewController animated:animated];
}

- (NSArray *)popToRootViewControllerAnimated:(BOOL)animated
{
    // 第一个隐藏导航条
    self.navigationBar.hidden = YES;
    return [super popToRootViewControllerAnimated:animated];
}
@end

#import <UIKit/UIKit.h>

@interface GXBaseViewController : UIViewController

@property (nonatomic,weak)UIButton *popBtn;
@property (nonatomic,weak)UIButton *pushBtn;

- (void)pop2Previous;
- (void)push2Next;
@end

//
//  GXBaseViewController.m
//  navigation的简单实用(纯代码)
//
//  Created by gxiangzi on 15/8/7.
//  Copyright (c) 2015年 itcast. All rights reserved.
//

#import "GXBaseViewController.h"

@interface GXBaseViewController ()
@end

@implementation GXBaseViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    // 创建返回的按钮
    UIButton* popBtn = [UIButton buttonWithType:UIButtonTypeCustom];
    [popBtn setTitle:@"返回上一个控制器" forState:UIControlStateNormal];
    [popBtn setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
    popBtn.backgroundColor = [UIColor grayColor];
    popBtn.frame = CGRectMake(100, 100, 200, 50);
    self.popBtn = popBtn;

    // 创建Push到下一个控制器
    UIButton* pushBtn = [UIButton buttonWithType:UIButtonTypeCustom];
    [pushBtn setTitle:@"push到下一个控制器" forState:UIControlStateNormal];
    [pushBtn setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
    pushBtn.backgroundColor = [UIColor grayColor];
    pushBtn.frame = CGRectMake(100, 300, 200, 50);
    self.pushBtn = pushBtn;

    // 注册监听事件
    [self.popBtn addTarget:self action:@selector(pop2Previous) forControlEvents:UIControlEventTouchUpInside];
    [self.pushBtn addTarget:self action:@selector(push2Next) forControlEvents:UIControlEventTouchUpInside];
}

#pragma mark - 子类重写
#pragma mark - 上一个
- (void)pop2Previous
{
    [self.navigationController popViewControllerAnimated:YES];
}

#pragma mark -下一个
- (void)push2Next
{
    [self.navigationController pushViewController:nil animated:YES];
}
@end