无法获得我刚刚在google drive上创建的文件夹ID

Question

public class Helpers  extends Activity implements
    GoogleApiClient.ConnectionCallbacks,
    GoogleApiClient.OnConnectionFailedListener {
SharedPreferences preferences;

private static final String TAG = "BaseDriveActivity";

public static  String EXISTING_FOLDER_ID;


protected static final int REQUEST_CODE_RESOLUTION = 1;

protected static final int NEXT_AVAILABLE_REQUEST_CODE = 2;

public static final String folderId = "FOLDER_ID";
public static final String fileName = "folderId";

private GoogleApiClient mGoogleApiClient;


@Override
protected void onResume() {
    super.onResume();
    if (mGoogleApiClient == null) {
        mGoogleApiClient = new GoogleApiClient.Builder(this)
                .addApi(Drive.API)
                .addScope(Drive.SCOPE_FILE)
                .addScope(Drive.SCOPE_APPFOLDER) // required for App Folder sample
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .build();
    }
    mGoogleApiClient.connect();
}

@Override
protected void onActivityResult(int requestCode, int resultCode,
                                Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == REQUEST_CODE_RESOLUTION && resultCode == RESULT_OK) {
        mGoogleApiClient.connect();
    }
}

@Override
protected void onPause() {
    if (mGoogleApiClient != null) {
        mGoogleApiClient.disconnect();
    }
    super.onPause();
}

final ResultCallback<DriveFolder.DriveFolderResult> callback = new ResultCallback<DriveFolder.DriveFolderResult>() {
    @Override
    public void onResult(DriveFolder.DriveFolderResult result) {
        if (!result.getStatus().isSuccess()) {
            showMessage("Error while trying to create the folder");
            return;
        }

        EXISTING_FOLDER_ID = result.getDriveFolder().getDriveId().toString();
        showMessage("Created a folder: " + result.getDriveFolder().getDriveId().toString());

        preferences = getSharedPreferences(fileName , MODE_PRIVATE);
        SharedPreferences.Editor editor = preferences.edit();
        editor.putString(folderId , EXISTING_FOLDER_ID );
        editor.apply();
    }
};

public  void mcreateFolder() {

    MetadataChangeSet changeSet = new MetadataChangeSet.Builder()
            .setTitle("SmsSync").build();
    Drive.DriveApi.getRootFolder(getGoogleApiClient()).createFolder(
            getGoogleApiClient(), changeSet).setResultCallback(callback);

}

@Override
public void onConnected(Bundle bundle) {
    Log.i(TAG, "GoogleApiClient connected");
    preferences = getSharedPreferences(fileName , MODE_PRIVATE);
    EXISTING_FOLDER_ID = preferences.getString(folderId ,null);
    if (EXISTING_FOLDER_ID == null ) {
        mcreateFolder();

    }

}

@Override
public void onConnectionSuspended(int cause) {
    Log.i(TAG, "GoogleApiClient connection suspended");
}

@Override
public void onConnectionFailed(ConnectionResult result) {
    Log.i(TAG, "GoogleApiClient connection failed: " + result.toString());
    if (!result.hasResolution()) {
        // show the localized error dialog.
        GooglePlayServicesUtil.getErrorDialog(result.getErrorCode(), this, 0).show();
        return;
    }
    try {
        result.startResolutionForResult(this, REQUEST_CODE_RESOLUTION);
    } catch (IntentSender.SendIntentException e) {
        Log.e(TAG, "Exception while starting resolution activity", e);
    }
}

public void showMessage(String message) {
    Toast.makeText(this, message, Toast.LENGTH_LONG).show();
}

public GoogleApiClient getGoogleApiClient() {
    return mGoogleApiClient;
}}

如果我使用result.getDriveFolder().getDriveID().getResourceID()获取id，那么它总是为null。
我首先使用此代码创建文件夹，并将其粘贴到https://github.com/googledrive/android-demos/blob/master/src/com/google/android/gms/drive/sample/demo/createFolderActivity.java

为了在文件夹中创建文件，我使用以下指南https://github.com/googledrive/android-demos/blob/master/src/com/google/android/gms/drive/sample/demo/createFileInFolderActivity.java
传递我保存的FolderID并将其传递到创建文件函数。

Answer 1

不要将DriveId与ResourceID混用。两者看起来都像字符串，但DriveId与ResourceID不同。参见SO21800257。另外，ResourceId并不是立即可用的，请参见SO 22874657。

DriveId通常看起来像：

“DriveID:caeshdbcmw1rvblahblahblahblahmyjaugssy8yyfrttnkru55”

由于许多开发人员都在争论这个问题，所以我将尽可能深入地阐述我的知识。

     Google Drive             Google Play Svcs      YourApp
   (up in the cloud)         (on your device)      (on your device)
  +--------------------+      +--------------+     +--------------+         
  | 'id' (RESTful API) | - - -> ResourceId  - - - -> ResourceId   |
  +--------------------+      |  DriveId    - - - -> DriveId      |
                              +--------------+     +--------------+

我试图用上面的艺术表达来传达的是：

>

当您在设备上创建驱动器对象（文件夹/文件）时，GooPlaySvcs将给您驱动器ID

您可以使用此DriveId与GooPlaySvcs进行本地通信，也可以缓存它，等等。

根据Daniel在SO 21800257（上面的链接）中的注释，不要依赖于DriveId是一个常量字符串，它应该随着提交的对象而改变。使用driveId.equals（）（我没有测试）

无论何时您走出本地设备（在不同设备上驱动web接口、其他应用程序、YourApp)，都需要使用ResourceId，这是驱动器上唯一唯一的ID（在云中：-）。

在GooPlaySvcs将对象提交到驱动器后，ResourceId可供您使用。有一些强制执行的方法，但这是另一回事（搜索requestSync（））。

如果您决定获取ResourceId并将其用于RESTfull调用（删除/垃圾），请注意以下事实：Google Play Services按照您无法控制的计划传播其更改（似乎是这样，请再次查看requestSync（）问题），并且REST/GDAA冲突可能会对数据造成损害。GDAA（GooPlayServices）可能有一段时间不知道您的REST更改。您必须自己管理同步。我承认我尝试的时候失败得很惨。