我正在使用Xamarin表单并为以下目标编写依赖服务：
我在这里尝试做的是在条目点击上从我的应用程序调用Files应用程序并且click事件似乎运行良好我的依赖服务调用完美但现在当我尝试使用UIDocumentPickerViewController时我无法获取View控制器上下文在我的依赖服务中调用PresentViewController方法。现在我知道了xamarin表单的上下文，但我不知道它是否会在这里工作，我甚至不知道使用它是否是一个明智的想法，因为它已经被标记为过时，因为我不是来自iOS背景，我不知道什么是正确的解决方案。
我的代码如下：
public class DocumentPickerRenderer : IDocumentPicker
{
public object PickFile()
{
var docPicker = new UIDocumentPickerViewController(new string[] { UTType.Data, UTType.Content }, UIDocumentPickerMode.Import);
docPicker.WasCancelled += (sender, wasCancelledArgs) =>
{
};
docPicker.DidPickDocumentAtUrls += (object sender, UIDocumentPickedAtUrlsEventArgs e) =>
{
Console.WriteLine("url = {0}", e.Urls[0].AbsoluteString);
//bool success = await MoveFileToApp(didPickDocArgs.Url);
var success = true;
string filename = e.Urls[0].LastPathComponent;
string msg = success ? string.Format("Successfully imported file '{0}'", filename) : string.Format("Failed to import file '{0}'", filename);
var alertController = UIAlertController.Create("import", msg, UIAlertControllerStyle.Alert);
var okButton = UIAlertAction.Create("OK", UIAlertActionStyle.Default, (obj) =>
{
alertController.DismissViewController(true, null);
});
alertController.AddAction(okButton);
PresentViewController(alertController, true, null);
};
PresentViewController(docPicker, true, null);
}
}
我的问题：
Hello Guys，您可以使用以下代码挑选使用iOS设备的代码中提及的任何类型的文档 -
使用以下界面：
public interface IMedia
{
Task<string> OpenDocument();
}
public Task<string> OpenDocument()
{
var task = new TaskCompletionSource<string>();
try
{
OpenDoc(GetController(), (obj) =>
{
if (obj == null)
{
task.SetResult(null);
return;
}
var aa = obj.AbsoluteUrl;
task.SetResult(aa.Path);
});
}
catch (Exception ex)
{
task.SetException(ex);
}
return task.Task;
}
static Action<NSUrl> _callbackDoc;
public static void OpenDoc(UIViewController parent, Action<NSUrl> callback)
{
_callbackDoc = callback;
var version = UIDevice.CurrentDevice.SystemVersion;
int verNum = 0;
Int32.TryParse(version.Substring(0, 2), out verNum);
var allowedUTIs = new string[]
{
UTType.UTF8PlainText,
UTType.PlainText,
UTType.RTF,
UTType.PNG,
UTType.Text,
UTType.PDF,
UTType.Image,
UTType.Spreadsheet,
"com.microsoft.word.doc",
"org.openxmlformats.wordprocessingml.document",
"com.microsoft.powerpoint.ppt",
"org.openxmlformats.spreadsheetml.sheet",
"org.openxmlformats.presentationml.presentation",
"com.microsoft.excel.xls",
};
// Display the picker
var pickerMenu = new UIDocumentMenuViewController(allowedUTIs, UIDocumentPickerMode.Import);
pickerMenu.DidPickDocumentPicker += (sender, args) =>
{
if (verNum < 11)
{
args.DocumentPicker.DidPickDocument += (sndr, pArgs) =>
{
UIApplication.SharedApplication.OpenUrl(pArgs.Url);
pArgs.Url.StopAccessingSecurityScopedResource();
var cb = _callbackDoc;
_callbackDoc = null;
pickerMenu.DismissModalViewController(true);
cb(pArgs.Url.AbsoluteUrl);
};
}
else
{
args.DocumentPicker.DidPickDocumentAtUrls += (sndr, pArgs) =>
{
UIApplication.SharedApplication.OpenUrl(pArgs.Urls[0]);
pArgs.Urls[0].StopAccessingSecurityScopedResource();
var cb = _callbackDoc;
_callbackDoc = null;
pickerMenu.DismissModalViewController(true);
cb(pArgs.Urls[0].AbsoluteUrl);
};
}
// Display the document picker
parent.PresentViewController(args.DocumentPicker, true, null);
};
pickerMenu.ModalPresentationStyle = UIModalPresentationStyle.Popover;
parent.PresentViewController(pickerMenu, true, null);
UIPopoverPresentationController presentationPopover = pickerMenu.PopoverPresentationController;
if (presentationPopover != null)
{
presentationPopover.SourceView = parent.View;
presentationPopover.PermittedArrowDirections = UIPopoverArrowDirection.Down;
}
}
现在您需要使用以下代码进行调用：
var filePath = await DependencyService.Get<IMedia>().OpenDocument();
对于Android中的选择文档，您可以使用以下代码
public class IntentHelper
{
public const int DocPicker = 101;
static Action<string> _callback;
public static async void ActivityResult(int requestCode, Result resultCode, Intent data)
{ if (requestCode == RequestCodes.DocPicker)
{
if (data.Data == null)
{
_callback(null);
}
else
{
var destFilePath = FilePath.GetPath(CurrentActivity, data.Data);
_callback(destFilePath);
}
}
}
public static Activity CurrentActivity
{
get
{
return (Xamarin.Forms.Forms.Context as MainActivity);
}
}
public static void OpenDocPicker(Action<string> callback)
{
_callback = callback;
var intent = new Intent(Intent.ActionOpenDocument);
intent.AddCategory(Intent.CategoryOpenable);
intent.SetType("*/*");
CurrentActivity.StartActivityForResult(intent, RequestCodes.DocPicker);
}
}
对于Android中的选择文档，您可以使用以下代码：
public class IntentHelper
{
public const int DocPicker = 101;
static Action<string> _callback;
public static async void ActivityResult(int requestCode, Result resultCode, Intent data)
{
if (requestCode == RequestCodes.DocPicker)
{
if (data.Data == null)
{
_callback(null);
}
else
{
var destFilePath = FilePath.GetPath(CurrentActivity, data.Data);
_callback(destFilePath);
}
}
}
public static Activity CurrentActivity
{
get
{
return (Xamarin.Forms.Forms.Context as MainActivity);
}
}
public static void OpenDocPicker(Action<string> callback)
{
_callback = callback;
var intent = new Intent(Intent.ActionOpenDocument);
intent.AddCategory(Intent.CategoryOpenable);
intent.SetType("*/*");
CurrentActivity.StartActivityForResult(intent, RequestCodes.DocPicker);
}
}
使用下面的代码来访问帮助程序类：public class Media：
IMedia {
public Task<string> OpenDocument() {
var task = new TaskCompletionSource<string>();
try {
IntentHelper.OpenDocPicker((path) => { task.SetResult(path); });
} catch (Exception ex) {
task.SetResult(null);
}
return task.Task;
}
}
因为我正在寻找UIDocumentPickerViewController而不是UIDocumentMenuViewController，所以其他答案并不是我想要的：
所以这就是我最终做到的方式：
调用文档选择器：
var docPicker = new UIDocumentPickerViewController(new string[]
{ UTType.Data, UTType.Content }, UIDocumentPickerMode.Import);
docPicker.WasCancelled += DocPicker_WasCancelled;
docPicker.DidPickDocumentAtUrls += DocPicker_DidPickDocumentAtUrls;
docPicker.DidPickDocument += DocPicker_DidPickDocument;
var _currentViewController = GetCurrentUIController();
if (_currentViewController != null)
_currentViewController.PresentViewController(docPicker, true, null);
GetCurrentUIController是获取当前UI控制器的函数，如下所示：
public UIViewController GetCurrentUIController()
{
UIViewController viewController;
var window = UIApplication.SharedApplication.KeyWindow;
if (window == null)
{
return null;
}
if (window.RootViewController.PresentedViewController == null)
{
window = UIApplication.SharedApplication.Windows
.First(i => i.RootViewController != null &&
i.RootViewController.GetType().FullName
.Contains(typeof(Xamarin.Forms.Platform.iOS.Platform).FullName));
}
viewController = window.RootViewController;
while (viewController.PresentedViewController != null)
{
viewController = viewController.PresentedViewController;
}
return viewController;
}
对于iOS 11以下，我添加了DidPickDocument事件：
private void DocPicker_DidPickDocument(object sender, UIDocumentPickedEventArgs e)
{
try
{
NSUrl filePath = e.Url.AbsoluteUrl;
//This is the url for your document and you can use it as you please.
}
catch (Exception ex)
{
}
}
对于iOS 11以上，你使用DidPickDocumentUrls，因为那里支持multipick：
private void DocPicker_DidPickDocumentAtUrls(object sender, UIDocumentPickedAtUrlsEventArgs e)
{
try
{
List<NSUrl> filePath = e.Urls.ToList().Select(y => y.AbsoluteUrl).ToList();
//returns the list of images selected
}
catch (Exception ex)
{
AppLogger.LogException(ex);
}
}