具有透明背景的 Objective-C 模态视图控制器

Question

我想创建一个具有透明背景的模态视图控制器，但是当我尝试将背景的 alpha 设置为 0.5 时，它只会让其后面的视图完全变黑。这是因为背景视图在转换后被移除。

self.view.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:0.5];
[self setModalPresentationStyle:UIModalPresentationFullScreen];
[self setDefinesPresentationContext:YES];

然后呈现视图控制器代码

SecondViewController *alertView = [[SecondViewController alloc] initWithNibName:@"SecondViewController" bundle:nil];
[self presentViewController:alertView animated:YES completion:nil];

请看链接 image/linke.gif

Answer 1

在firstViewController 中的按钮操作中尝试此代码以更改视图控制器并呈现一个新类secondViewController

  secondViewController *VC = [self.storyboard instantiateViewControllerWithIdentifier:@"secondViewController"];

    VC.view.backgroundColor=[UIColor colorWithWhite:0 alpha:0.1f];
    VC.modalPresentationStyle=UIModalPresentationOverCurrentContext;
    [self presentViewController:VC animated:NO completion:nil];