如何获取Google驱动器文档的文件名和实际路径？

Question

我使用以下代码来获取文件管理器中的文件名和文件路径。但是，它不会返回Google云端硬盘文件的路径。知道如何获得实际路径吗？

我的代码 -

public String getFilePath() {
    if (uri.getScheme().equalsIgnoreCase("file")) {
        return uri.getLastPathSegment();
    }

    cursorLoader.setUri(uri);
    cursorLoader.setProjection(projections);
    Cursor cursor = cursorLoader.loadInBackground();
    int column_index = cursor.getColumnIndexOrThrow(MediaStore.Files.FileColumns.DATA);
    cursor.moveToFirst();
    String realPath = cursor.getString(column_index);
    cursor.close();

    if (realPath == null || realPath.isEmpty()) {
        return null;
    }

return null;
}

Answer 1

您必须使用URI。通过URI你可以getContentResolver.query(theUriThatYouHave, null, null, null, null)。现在你有了一个游标，你可以检查列名等。

对于Google云端硬盘，列名为_display_name。这将为您提供文件名。

现在您想要访问该文件？你可以通过InputStream打开一个getContentResolver().openInputStream(theUriThatYouHave)到URI。

Answer 2

通过以下步骤轻松获取Google云端硬盘URI中的文件名和实际路径：

1. 在Android清单文件中添加文件提供程序路径。

   <?xml version="1.0" encoding="utf-8"?>
   <manifest xmlns:android="http://schemas.android.com/apk/res/android"
       package="com.demo.filemangerdemo">
       <uses-permission android:name="android.permission.INTERNET" />
       <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
       <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
       <uses-permission android:name="android.permission.STORAGE" />
       <application
           android:allowBackup="true"
           android:icon="@mipmap/ic_launcher"
           android:label="@string/app_name"
           android:roundIcon="@mipmap/ic_launcher_round"
           android:supportsRtl="true"
           android:theme="@style/AppTheme">
           <activity android:name="com.demo.filemangerdemo.activity.MainActivity">
               <intent-filter>
                   <action android:name="android.intent.action.MAIN" />
   
                   <category android:name="android.intent.category.LAUNCHER" />
               </intent-filter>
           </activity>
           <provider
               android:name="android.support.v4.content.FileProvider"
               android:authorities="${applicationId}.provider"
               android:exported="false"
               android:grantUriPermissions="true">
               <meta-data
                   android:name="android.support.FILE_PROVIDER_PATHS"
                   android:resource="@xml/provider_paths"/>
           </provider>
       </application>
   </manifest>

2. 在res下创建xml文件夹并添加provider_paths.xml。

   <?xml version="1.0" encoding="utf-8"?>
   <paths xmlns:android="http://schemas.android.com/apk/res/android">
       <cache-path
           name="my_cache"
           path="." />
       <cache-path
           name="cache"
           path="." />
       <external-cache-path
           name="external_cache"
           path="." />
       <files-path
           name="files"
           path="." />
   </paths>

3. Utils类用于访问Google云端硬盘的数据。

   public class Utils {
       private static Uri contentUri = null;
   
       @SuppressLint("NewApi")
       public static String getPath(final Context context, final Uri uri) {
           // check here to KITKAT or new version
           final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
           // DocumentProvider
           if (isKitKat && DocumentsContract.isDocumentUri(context, uri))
             {
               // MediaProvider
                if (isMediaDocument(uri)) {
                    if (isGoogleDriveUri(uri)) {
                   return getDriveFilePath(uri, context);
               }
   
   
             }
         }

4. 是GoogleDriveUri方法

   private static boolean isGoogleDriveUri(Uri uri) {
       return "com.google.android.apps.docs.storage".equals(uri.getAuthority()) || "com.google.android.apps.docs.storage.legacy".equals(uri.getAuthority());
   }

5. getDriveFilePath方法

   private static String getDriveFilePath(Uri uri, Context context) {
       Uri returnUri = uri;
       Cursor returnCursor = context.getContentResolver().query(returnUri, null, null, null, null);
       /*
        * Get the column indexes of the data in the Cursor,
        *     * move to the first row in the Cursor, get the data,
        *     * and display it.
        * */
       int nameIndex = returnCursor.getColumnIndex(OpenableColumns.DISPLAY_NAME);
       int sizeIndex = returnCursor.getColumnIndex(OpenableColumns.SIZE);
       returnCursor.moveToFirst();
   
       String name = (returnCursor.getString(nameIndex));
       String size = (Long.toString(returnCursor.getLong(sizeIndex)));
       File file = new File(context.getCacheDir(), name);
       try {
           InputStream inputStream = context.getContentResolver().openInputStream(uri);
           FileOutputStream outputStream = new FileOutputStream(file);
           int read = 0;
           int maxBufferSize = 1 * 1024 * 1024;
           int bytesAvailable = inputStream.available();
   
           //int bufferSize = 1024;
           int bufferSize = Math.min(bytesAvailable, maxBufferSize);
   
           final byte[] buffers = new byte[bufferSize];
           while ((read = inputStream.read(buffers)) != -1) {
               outputStream.write(buffers, 0, read);
           }
           Log.e("File Size", "Size " + file.length());
           inputStream.close();
           outputStream.close();
           Log.e("File Path", "Path " + file.getPath());
       } catch (Exception e) {
           Log.e("Exception", e.getMessage());
       }
           return file.getPath();
       }     
   }

6. 获取onActivityResult中的文件路径

   protected void onActivityResult(int requestCode, int resultCode, Intent data) {
       super.onActivityResult(requestCode, resultCode, data);
       if (requestCode == REQUEST_CODE && resultCode == RESULT_OK) {
           if ((data != null) && (data.getData() != null)) {
               Uri selectedFile = data.getData();
               if (selectedFile.getLastPathSegment() != null) {
                   //Here you will get File Path
                   String strPath = FileUtils.getPath(this, selectedFile);  
               }
           }
       }
   }