Question

我使用以下代码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，您可以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，有一个列名_display_name。这将为您提供文件名。

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

Answer 2

通过以下步骤非常容易地从Google云端硬盘URI获取文件名和真实路径：

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>

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>

用于从Google云端硬盘访问数据的实用程序类。

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);
            }


          }
      }

isGoogleDriveUri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());
}

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();
    }     
}

在onActivityResult中获取文件路径

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);  
            }
        }
    }
}

如何获取Google驱动器文档的文件名和实际路径？

2 个答案: