Question

我想在特定操作发生后在代码中打开一个Popover（例如，点按一个按钮）。

以下代码让我打开一个带有NavigationBar的Popover，但它看起来不像我用IB做的那个。（IB方法是在UINavigationController中嵌入UIViewController并定义两个按钮取消并保存）。我唯一想要的是在Popover上放置这两个按钮。我没有使用任何导航功能！

        var cell = grid.VisibleCellAtCoordinate(coordinate) as SDataGridTextCell;

        var viewController = new UIViewController();
        var navBar = new UINavigationBar(new RectangleF(0, 0, viewController.View.Bounds.Width, 50)) 
        {
            AutoresizingMask = UIViewAutoresizing.FlexibleWidth,
            BarStyle = UIBarStyle.Black, 
            Translucent = true, 
            Items = new[] 
            { 
                new UINavigationItem("test") 
                { 
                    LeftBarButtonItem = new UIBarButtonItem(UIBarButtonSystemItem.Cancel, (s, e) => { _popoverController.Dismiss(true); }),
                    RightBarButtonItem = new UIBarButtonItem(UIBarButtonSystemItem.Save, (s, e) => { _popoverController.Dismiss(true); })
                }
            }
        };

        var textField = new UITextField(new RectangleF(0, 50, viewController.View.Bounds.Width, viewController.View.Bounds.Height)) { Placeholder = "Mein Text...", BackgroundColor = UIColor.White };
        textField.BecomeFirstResponder();


        viewController.View.Add(navBar);
        viewController.View.Add(textField);
        viewController.View.SubviewAdded(textField);
        _popoverController = new UIPopoverController(viewController);
        _popoverController.SetPopoverContentSize(new SizeF(250, 200), false);
        _popoverController.PresentFromRect(cell.Bounds, cell, UIPopoverArrowDirection.Any, false);

这些按钮看起来像这个图像（丑陋）：
Ugly - From Code

此图像显示了在IB中创建时的外观：
Nice - From IB

Answer 1

这是在popover中使用独立导航栏的一个警告。据我所知，将视图控制器嵌入导航控制器是避免它的唯一方法。

Answer 2

将内容视图（UIViewController）正确嵌入到 UINavigationController 有一些问题，因为我试图每次直接将导航栏项（按钮）添加到 UINavigationController ' s NavigationItem 属性。但这必须通过内容视图控制器来完成......

        var contentViewController = new UIViewController();
        var textField = new UITextField(contentViewController.View.Bounds)
        {
            BackgroundColor = UIColor.White,
            AutoresizingMask = ~UIViewAutoresizing.None,
            Placeholder = "My Text..."
        };
        contentViewController.View.Add(textField);

        var navigationController = new UINavigationController(contentViewController);
        contentViewController.Title = "Popover";
        contentViewController.NavigationItem.LeftBarButtonItem = new UIBarButtonItem(UIBarButtonSystemItem.Cancel, (s, e) => { _popoverController.Dismiss(false); });
        contentViewController.NavigationItem.RightBarButtonItem = new UIBarButtonItem(UIBarButtonSystemItem.Save, (s, e) => { _popoverController.Dismiss(false); });

        _popoverController = new UIPopoverController(navigationController);
        _popoverController.SetPopoverContentSize(new SizeF(300, 300), false);
        _popoverController.PresentFromRect(button1.Bounds, button1, UIPopoverArrowDirection.Any, false);

如果以编程方式创建，UIPopoverController中的UINavigationBar看起来很难看

2 个答案: