iOS开发之presentViewController、presentModelViewController和pushViewController

本来这个应该是昨天发出来的，昨天时间来不及就放到今天发了。

昨天在开发中遇到一个问题：从ViewController push一个视图，返回的时候返回不了；查看代码发现push方法、pop方法都没问题；话不多说，直接上代码：

- (void)AddNewFeedBacks

{

FeedBackViewController *feedBackView = [[FeedBackViewController alloc] init];
UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController:feedBackView];
[self.navigationController presentViewController:nav animated:YES completion:nil];

}

- (void)popBack

{

    [self.navigationController popViewControllerAnimated:YES];

}

UIBarButtonItem *leftItem = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:@"reback.png"] style:UIBarButtonItemStylePlain target:self action:@selector(popBack)];

self.navigationItem.leftBarButtonItem = leftItem;

方法控件都没问题；这时候就不得不断点来看，结果发现到popBack方法的时候这个方法没生效，于是查看了navigationController的一些push、pop方法结果发现了问题出在退出视图，也就是[self.navigationController presentViewController:nav animated:YES completion:nil];这里。

然后去查看了下相关api发现这两个方法的区别：

这两个方法都是必须要ViewController, 是建立在UINavigationController之上的。
SQLiteViewController *baSQLiteViewController = [[SQLiteViewController alloc] init];
UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController:baSQLiteViewController];
[self.window addSubview:nav.view];

推出视图push，下一页面会自动添加返回按钮
InforViewController *baInforViewController = [[InforViewController alloc] init];
[self.navigationController pushViewController:baInforViewController animated:YES];

 

以Modal方式推出一个视图，弹出的视图没有返回按钮，需要自己添加
NewDataViewController *baNewViewController = [[NewDataViewController alloc] init];
UINavigationController *baNavigation = [[UINavigationController alloc] initWithRootViewController:baNewViewController];
[self.navigationController presentModalViewController:baNavigation animated:YES];
[baNewViewController release];
[baNavigation release];

为弹出视图添加返回按钮
self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"返回" style:UIBarButtonItemStyleDone target:self action:@selector(returnView)];

返回方法
- (void)returnView

{
    [self.parentViewController dismissModalViewControllerAnimated:YES];
}