点击“快速查看”图标后，文档未打开

Question

我的任务是实现快速查看功能，以显示打开所选文档的选项。我正在使用 UIDocumentInteractionController 的 PresentOptionsMenu 方法来显示选项。显示了“快速查看”图标，但是当我单击它时没有任何反应。带有选项的弹出窗口关闭，文档未打开。

我做错了什么？为什么点击“快速查看”图标后文档打不开？

The popup displayed after selecting a document

我的代码是：

public class DataViewer
{
     public event EventHandler DocumentOpened;

     public async Task OpenDocument(string filePath)
     {
         var viewer = UIDocumentInteractionController.FromUrl(new NSUrl(filePath, false));
         viewer.WillBeginSendingToApplication += async (sender, args) =>
         {
             DocumentOpened?.Invoke(this, EventArgs.Empty);
         };
         var controller = UIApplication.SharedApplication.KeyWindow.RootViewController;
         viewer.PresentOptionsMenu(controller.View.Frame, controller.View, true);
     }
}

Answer 1

需要注明ViewController 呈现文档预览。

尝试在委托 UIDocumentInteractionControllerDelegate 中实现方法 ViewControllerForPreview。

var viewer = UIDocumentInteractionController.FromUrl(new NSUrl(filePath, false));
viewer.WillBeginSendingToApplication += async (sender, args) =>
{
    DocumentOpened?.Invoke(this, EventArgs.Empty);
};
var controller = UIApplication.SharedApplication.KeyWindow.RootViewController;

viewer.Delegate = new MyClass(controller);   //add this line
viewer.PresentOptionsMenu(controller.View.Frame, controller.View, true);


 public class MyClass : UIDocumentInteractionControllerDelegate
    {
        readonly UIViewController _controller;
        public MyClass(UIViewController controller)
        {
            _controller = controller;
        }

        public override UIViewController ViewControllerForPreview(UIDocumentInteractionController controller)
        {
            return _controller;
        }

        public override UIView ViewForPreview(UIDocumentInteractionController controller)
        {
            return _controller.View;
        }
    }

参考

点击“快速查看”图标后，文档未打开

After tapping on the Quick Look icon the document is not opened

c#

quicklook

xamarin.ios

xamarin.forms