Xamarin：不确定使用DriveFile.Open投射什么 [英] Xamarin: Unsure what to cast using DriveFile.Open

问题描述

我试图查找关于Xamarin的DriveFile.Open的文档，但是仍然无法找到要从下面的代码中返回声明的类。

  var pendingResult = driveFile.Open（..，..，..）
 var obj = pendingResult.await（）; 
  

在Android文档中，要投射到的类为

  DriveContents driveContents = driveContentsResult.getDriveContents（）; 
  

但是我找不到名为DriveContentsResult的类。

OnResult 回调）

解决方案 pre> driveFile.Open（_googleApiClient，DriveFile.ModeReadOnly，null）.SetResultCallback（this）;


会调用 onResult ，您可以投射结果：

pre $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ var contentResults =（结果）.JavaCast< IDriveApiDriveContentsResult>（）;
var driveContent = contentResults.DriveContents;
D.WriteLine（driveContent.DriveId）;

$ b

异步方式：

  var driveContentResult = driveFile.OpenAsync（_googleApiClient，DriveFile.ModeReadOnly，null）.ContinueWith（（resultTask）=> 
 {
 var driveContentResults = resultTask.Result; 
 var driveContent = driveContentResults.DriveContents; 
 D.WriteLine（driveContent.DriveId）; 
}）; 
  

I tried to lookup the documentation about DriveFile.Open for Xamarin but still can't find the class to cast the return statement from the code below

var pendingResult = driveFile.Open(.. , .., ..) 
var obj = pendingResult.await();

On Android Documentation, the class to be casting to is

DriveContents driveContents = driveContentsResult.getDriveContents();

But i can't find the Class called DriveContentsResult.

解决方案

Non-Async way (using OnResult callback)

driveFile.Open(_googleApiClient, DriveFile.ModeReadOnly, null).SetResultCallback(this);

Will call onResult and there you can cast the result:

void IResultCallback.OnResult(Java.Lang.Object result)
{
    var contentResults = (result).JavaCast<IDriveApiDriveContentsResult>();
    var driveContent = contentResults.DriveContents;
    D.WriteLine(driveContent.DriveId);

}

Async way:

var driveContentResult = driveFile.OpenAsync(_googleApiClient, DriveFile.ModeReadOnly, null).ContinueWith((resultTask) =>
{
    var driveContentResults = resultTask.Result;
    var driveContent = driveContentResults.DriveContents;
    D.WriteLine(driveContent.DriveId);
});

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