ios - 从 UIWindow 中移除 UIViewController 的 View

Question

当用户单击添加按钮时，我将在 UIWindow 上添加 View 。现在，如果用户再次点击添加按钮，我想先删除该 View 并再次添加。

我已使用此代码在 UIWindow 上添加 View :

ProgressVC *vc = [[UIStoryboard storyboardWithName:@"Main" bundle:nil] instantiateViewControllerWithIdentifier:@"IDProgressVC"];
[[[[UIApplication sharedApplication] delegate]window] addSubview:vc.view];

对于删除，我已经尝试过此代码:

[vc.view removeFromSuperview];
[[[[UIApplication sharedApplication] delegate]window] setNeedsLayout];
vc = nil;

我们将不胜感激。

Answer 1

试试这个

// Make this global property

@property(nonatomic, strong) UIView * currentView;

//store the view in gloabal property
ProgressVC *vc = [[UIStoryboard storyboardWithName:@"Main" bundle:nil] instantiateViewControllerWithIdentifier:@"IDProgressVC"];
currentView = vc.view;
[[[[UIApplication sharedApplication] delegate]window] addSubview:currentView];

//remove it 
[currentView removeFromSuperview];
[[[[UIApplication sharedApplication] delegate]window] setNeedsLayout];
currentView = nil;