錯誤應用試圖呈現拆分視圖控制器模態

Question

我用故事板，我想加載一組特定的XIBs的，問題是，我得到這個錯誤：

'NSInvalidArgumentException', reason: 'Application tried to present a Split View Controllers modally <PlaceHolderViewController: 0x38e890> 

在PlaceHolderViewController我有一個按鈕，用這段代碼加載xib，我沒有問題從iPhone加載xib，但在iPad上我遇到了這個問題。

這是代碼：

- (IBAction)actionButtonConversor:(id)sender { 
    ConverterViewController *converterViewController; 
    UnitSelectViewController *unitSelectViewController; 

    if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) { 
     converterViewController = [[ConverterViewController alloc] initWithNibName:@"ConverterViewController_iPhone" bundle:nil]; 
     unitSelectViewController= [[UnitSelectViewController alloc] initWithNibName:@"UnitSelectViewController_iPhone" bundle:nil]; 
     self.navigationController = [[UINavigationController alloc] initWithRootViewController:converterViewController]; 
     self.navigationController.navigationBar.tintColor = [UIColor colorWithRed:0.0f green:0.48235297203063965f blue:0.63137257099151611f alpha:1]; 
     [self presentModalViewController:self.navigationController animated:YES]; 
    } else { 
     converterViewController = [[ConverterViewController alloc] initWithNibName:@"ConverterViewController_iPad" bundle:nil]; 
     unitSelectViewController= [[UnitSelectViewController alloc] initWithNibName:@"UnitSelectViewController_iPad" bundle:nil]; 
     UINavigationController *masterNavigationController = [[UINavigationController alloc] initWithRootViewController:unitSelectViewController]; 
     UINavigationController *detailNavigationController = [[UINavigationController alloc] initWithRootViewController:converterViewController]; 
     masterNavigationController.navigationBar.tintColor = [UIColor colorWithRed:0.0f green:0.48235297203063965f blue:0.63137257099151611f alpha:1]; 
     detailNavigationController.navigationBar.tintColor = [UIColor colorWithRed:0.0f green:0.48235297203063965f blue:0.63137257099151611f alpha:1]; 

     self.splitViewController = [[UISplitViewController alloc] init]; 

     self.splitViewController.delegate = converterViewController; 

     self.splitViewController.viewControllers = [NSArray arrayWithObjects:masterNavigationController, detailNavigationController, nil]; 
     [self presentModalViewController:self.splitViewController animated:YES]; // ERROR comes from here i think 
    } 

    unitSelectViewController.delegate = converterViewController; 
    converterViewController.unitSelectViewController = unitSelectViewController; 
} 

Answer 1

問題看起來明顯。以下是從UISplitViewController文件複製：

"you must always install the view from a UISplitViewController object as the root view of your application’s window. [...] Split view controllers cannot be presented modally."

換句話說，你看到的是預期的行爲。