容器视图中的 UI 未更新

UI in Container View is not updating

我有一个带有按钮的视图,当用户按下按钮时,会显示一个容器视图。我使用:

ContainerView.setNeedsDisplay()

更新容器视图。我这样做是因为我有 UI 标签,我希望文本基于单击的按钮。

问题是在更新视图和更新文本时,标签文本没有改变。

我写了一个 Helper 来做这个,来源可能对你有帮助:

+ (void)navigateFromController:(UIViewController *)fromController toController:(UIViewController *)toController {
    if (fromController) {
        // Remove any existing child controllers.
        for (UIViewController *child in [toController childViewControllers]) {
            [child willMoveToParentViewController:nil];
            [child.view removeFromSuperview];
            [child removeFromParentViewController];
        }

        // Embed the new controller.
        [fromController addChildViewController:toController];

        toController.view.frame = fromController.view.bounds;
        toController.view.translatesAutoresizingMaskIntoConstraints = false;
        [fromController.view addSubview:toController.view];

        [toController.view.leftAnchor constraintEqualToAnchor:fromController.view.leftAnchor].active = YES;
        [toController.view.rightAnchor constraintEqualToAnchor:fromController.view.rightAnchor].active = YES;
        [toController.view.topAnchor constraintEqualToAnchor:fromController.view.topAnchor].active = YES;
        [toController.view.bottomAnchor constraintEqualToAnchor:fromController.view.bottomAnchor].active = YES;

        [fromController didMoveToParentViewController:fromController];
    }
}

感谢 Rroobb 的评论,有用! -计算器。com/a/37748737/3108877