从导航堆栈中删除viewController时发出问题

Question

我正在制作演示，我必须从NavigationController中删除一些viewControllers，为此我已经实现了下面的代码，但它给了我一个问题。

我已经推送了VC1，VC2，VC3，现在我想推送VC4并删除VC2 ......

ViewController4 *VC4=[[ViewController4 alloc]initWithNibName:@"ViewController4" bundle:nil];
[self.navigationController pushViewController:VC4 animated:YES];

NSMutableArray *viewControllers = [NSMutableArray arrayWithArray:[[self navigationController] viewControllers]];

for(UIViewController *objVC in viewControllers)
{
    if([objVC isKindOfClass:[ViewController2 class]])
    {
        [viewControllers removeObjectIdenticalTo:objVC];
    }
}
self.navigationController.viewControllers =viewControllers ;

此代码适用于iOS8，但在带有VC2的iOS7中，当我按下VC4中的后退按钮时，VC3也会自动删除。 即使我在下面放置代码，控制器也会自动从堆栈中删除。

ViewController4 *VC4=[[ViewController4 alloc]initWithNibName:@"ViewController4" bundle:nil];
[self.navigationController pushViewController:VC4 animated:YES];

NSMutableArray *viewControllers = [NSMutableArray arrayWithArray:[[self navigationController] viewControllers]];

self.navigationController.viewControllers =viewControllers ;

Answer 1

这是修复，在iOS7和iOS8中正常工作：

NSMutableArray *viewControllers = [NSMutableArray arrayWithArray:[[self navigationController] viewControllers]];

    // Find the things to remove
        NSMutableArray *toDelete = [NSMutableArray array];

    for(UIViewController *objVC in viewControllers)
    {
        if([objVC isKindOfClass:[ViewController2 class]])
        {
            [toDelete addObject:objVC];
        }
    }
    [viewControllers removeObjectsInArray:toDelete];
    self.navigationController.viewControllers =viewControllers ;

ViewController4 *VC4=[[ViewController4 alloc]initWithNibName:@"ViewController4" bundle:nil];
[self.navigationController pushViewController:VC4 animated:YES];