Android Uri和文件路径互相转换的实例代码

在项目中需要用到将Uri转换为绝对路径，在网上找到一个方法，做个笔记

网上有不少方法，但是有的对4.4后的版本无效，这里的方法可以在4.4之后的版本将Uri转换为绝对路径

public class GetPathFromUri {
  /**
   * 专为Android4.4设计的从Uri获取文件绝对路径
   */
  public static String getPath(final Context context, final Uri uri) {
    final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
    // DocumentProvider
    if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
      // ExternalStorageProvider
      if (isExternalStorageDocument(uri)) {
        final String docId = DocumentsContract.getDocumentId(uri);
        final String[] split = docId.split(":");
        final String type = split[0];
        if ("primary".equalsIgnoreCase(type)) {
          return Environment.getExternalStorageDirectory() + "/" + split[1];
        }
      }
      // DownloadsProvider
      else if (isDownloadsDocument(uri)) {
        final String id = DocumentsContract.getDocumentId(uri);
        final Uri contentUri = ContentUris.withAppendedId(
            Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));
        return getDataColumn(context, contentUri, null, null);
      }
      // MediaProvider
      else if (isMediaDocument(uri)) {
        final String docId = DocumentsContract.getDocumentId(uri);
        final String[] split = docId.split(":");
        final String type = split[0];
        Uri contentUri = null;
        if ("image".equals(type)) {
          contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
        } else if ("video".equals(type)) {
          contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
        } else if ("audio".equals(type)) {
          contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
        }
        final String selection = "_id=?";
        final String[] selectionArgs = new String[]{split[1]};
        return getDataColumn(context, contentUri, selection, selectionArgs);
      }
    }
    // MediaStore (and general)
    else if ("content".equalsIgnoreCase(uri.getScheme())) {
      return getDataColumn(context, uri, null, null);
    }
    // File
    else if ("file".equalsIgnoreCase(uri.getScheme())) {
      return uri.getPath();
    }
    return null;
  }
  /**
   * Get the value of the data column for this Uri. This is useful for
   * MediaStore Uris, and other file-based ContentProviders.
   *
   * @param context    The context.
   * @param uri      The Uri to query.
   * @param selection   (Optional) Filter used in the query.
   * @param selectionArgs (Optional) Selection arguments used in the query.
   * @return The value of the _data column, which is typically a file path.
   */
  public static String getDataColumn(Context context, Uri uri, String selection,
                String[] selectionArgs) {
    Cursor cursor = null;
    final String column = "_data";
    final String[] projection = {column};
    try {
      cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs,
          null);
      if (cursor != null && cursor.moveToFirst()) {
        final int column_index = cursor.getColumnIndexOrThrow(column);
        return cursor.getString(column_index);
      }
    } finally {
      if (cursor != null)
        cursor.close();
    }
    return null;
  }
  /**
   * @param uri The Uri to check.
   * @return Whether the Uri authority is ExternalStorageProvider.
   */
  public static boolean isExternalStorageDocument(Uri uri) {
    return "com.android.externalstorage.documents".equals(uri.getAuthority());
  }
  /**
   * @param uri The Uri to check.
   * @return Whether the Uri authority is DownloadsProvider.
   */
  public static boolean isDownloadsDocument(Uri uri) {
    return "com.android.providers.downloads.documents".equals(uri.getAuthority());
  }
  /**
   * @param uri The Uri to check.
   * @return Whether the Uri authority is MediaProvider.
   */
  public static boolean isMediaDocument(Uri uri) {
    return "com.android.providers.media.documents".equals(uri.getAuthority());
  }
} 

绝对路径转Uri比较简单

以绝对路径创建一个File对象，然后调用

Uri.fromFile(file)

以上所述是小编给大家介绍的Android Uri和文件路径互相转换的实例代码，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对我们网站的支持！