从嵌套在 UIScrollview 中的 ViewController 呈现ModalViewController？

Question

我正在创建一个iPhone应用程序，并且在从嵌套在Scrollview中的viewController运行presentModalViewController代码时遇到问题，当我单击按钮来呈现下一个视图控制器时，我会看到一个缓慢的动画和两秒钟的空白屏幕。

从我的 AppDelegate 中，我将 rootViewController 设置为 ViewController （其中包含设置滚动视图布局的代码），

我基本上在滚动视图内加载两个视图控制器，以便用户可以下拉屏幕以查看历史记录。

AppDelegateCode

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions

{

[application setStatusBarStyle:UIStatusBarStyleBlackOpaque];  

self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
ViewController *controller =  [[[ViewController alloc] initWithNibName:@"ViewController" bundle:nil] autorelease];
self.window.rootViewController = controller; //self.viewController;
[self.window makeKeyAndVisible];
return YES;

}

ViewController 代码

- (void)viewWillAppear:(BOOL)animated

{ [超级viewWillAppear：动画]；

CGRect bounds = self.view.bounds;

vScroller.bounces = NO;
vScroller.pagingEnabled = YES;
vScroller.showsVerticalScrollIndicator = FALSE;
vScroller.alwaysBounceVertical = FALSE;

vScroller.contentSize = CGSizeMake(bounds.size.width, bounds.size.height * 2);

// History View Controller..
historyViewController *historyView = [[historyViewController alloc] initWithNibName:@"historyViewController" bundle:nil];

[vScroller addSubview:historyView.view];
[historyView release];

// Reconfigure Content Offset
vScroller.contentOffset = CGPointMake(0, bounds.size.height);

// Calculator View Controller
mainCalculatorViewController *mainView = [[mainCalculatorViewController alloc] initWithNibName:@"mainCalculatorViewController" bundle:nil];
mainView.view.frame = CGRectOffset(bounds, 0, bounds.size.height);
[vScroller addSubview:mainView.view];

}

ma​​inCalculatorViewController 信息按钮代码

  - (IBAction)btnInfo:(id)sender 
    {
        infoViewController *controller = [[infoViewController alloc] initWithNibName:@"infoViewController" bundle:nil];

        controller.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
        [self presentModalViewController:controller animated:YES];
        [controller release];
    }

问题是，当单击信息按钮时，我得到的动画很糟糕，在我看来，按钮和presentModal 视图控制器可能应该从保存嵌套滚动视图的父ViewController 运行但我不确定如何做到这一点。

任何提示或建议都会很棒。

谢谢亚伦

Answer 1

首先，我不知道界面生成器是如何做到这一点的。但以编程方式，您可能应该创建一个新的 navigationController 来处理 modalVC。

-(void)showModalVC
{
    self.myModalVC = [[ModalVC alloc] init];

    self.myModalVC.dismissDelegate = self;

    UINavigationController *navController = [[UINavigationController alloc]
                                             initWithRootViewController:self.myModalVC];

    navController.modalPresentationStyle = UIModalPresentationFormSheet; //or something similar, this one is used on an iPad

    UILabel *navTopItemTitle = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 300, 44)];
    navTopItemTitle.text = @"Modal shizzle";
    navTopItemTitle.backgroundColor = [UIColor clearColor];
    navTopItemTitle.textColor = [UIColor whiteColor];
    navTopItemTitle.textAlignment = UITextAlignmentCenter;

    [navController.navigationBar.topItem setTitleView:navTopItemTitle];

    [self presentModalViewController:navController animated:YES];

    [self.addTabViewController release];
    [navController release];
}

这就是我使用 ModalVC 的方式。

我希望它对你有用。

祝你好运。