ios基础篇（十一）——UINavgationController的使用（二）页面切换

上篇说到了添加UIBarButtonItem，接下来说说界面切换；

1、首先我们在刚才的RootViewController中添加一个按钮用来实现跳转：

打开RootViewController.m(我就继续写了)，添加一个跳转button：

效果图：

2、button动作实现，新建一个NewViewController继承自UIViewController；用pushViewController到navigationController中去；

#import "NewViewController.h"

- (void)nextAction{
    
    NewViewController *NewVC = [[NewViewController alloc] init];
    [self.navigationController pushViewController:NewVC animated:YES];
    NewVC.title = @"NewViewController";
}

点击button,如图Back为系统自带按钮；

如果不想使用系统自带按钮，我们可以自定义按钮：

 UIBarButtonItem *backButton = [[UIBarButtonItem alloc] initWithTitle:@"返回"style:UIBarButtonItemStyleDone target:nil action:nil];
    self.navigationItem.backBarButtonItem = backButton;

如图：

3、title的自定义：

#import "NewViewController.h"

@interface NewViewController ()

@end

@implementation NewViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.

    UILabel *title = [[UILabel alloc] init];
    title.text = @"标题";
    title.font = [UIFont systemFontOfSize:20];
    [title sizeToFit];
    self.navigationItem.titleView = title;
    
}

效果图：

4、如果想放置多个按钮：

SegmentedControl又被称作分段控制器，可以一下放置多个按钮又不影响美观：

 NSArray *colorArray = @[@"黑", @"白", @"灰"];
    UISegmentedControl *segmentCtrl = [[UISegmentedControl alloc] initWithItems:colorArray];
    segmentCtrl.selectedSegmentIndex = 1;
    segmentCtrl.tintColor = [UIColor redColor];
    self.navigationItem.titleView = segmentCtrl;

效果图：

添加点击响应事件：

[segmentCtrl addTarget:self action:@selector(segmentAction:) forControlEvents:UIControlEventValueChanged];

- (void)segmentAction:(id)segment{

    switch ([segment selectedSegmentIndex]) {
        case 0:
        {
            UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"提示" message:@"您选择了颜色黑" delegate:self cancelButtonTitle:@"是" otherButtonTitles:@"否", nil];
            [alert show];

        }
            break;
        case 1:
        {
            UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"提示" message:@"您选择了颜色白" delegate:self cancelButtonTitle:@"是" otherButtonTitles:@"否", nil];
            [alert show];
            
        }
            break;
        case 2:
        {
            UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"提示" message:@"您选择了颜色灰" delegate:self cancelButtonTitle:@"是" otherButtonTitles:@"否", nil];
            [alert show];
            
        }
            break;

        default:
            break;
    }
}

效果图：