File Subsystem Changelog

cl.file.1 Change of the mediaLibrary Interface Compatibility

Changed the compatibility of some mediaLibrary APIs.

Change Impact

The compatibility of some mediaLibrary APIs is changed. For applications developed based on earlier versions, pay attention to the iterative update of deprecated APIs.

Key API/Component Changes

Adaptation Guide

getFileAssets

From API version 10, the albums represented by physical directories are replaced by logical albums, which allow multiple files in an album and presence of a file in multiple albums. This design, however, makes parent, albumId, albumUri, and albumName incompatible. They cannot be used as parameters of MediaFetchOptions in getFileAssets(). The following is an example of incorrect use of the APIs.

1. Call getMediaLibrary to obtain a MediaLibrary instance.
2. Call MediaFetchOptions to create the file fetching options.
3. Call getFileAssets to obtain file assets.

Example (incorrect):

import mediaLibrary from '@ohos.multimedia.mediaLibrary';

async function example() {
  try {
    let context = getContext(this);
    let media = mediaLibrary.getMediaLibrary(context);
    let fileKeyObj = mediaLibrary.FileKey;
    let albumId = 1;
    let getImageOp = {
      selections: fileKeyObj.ALBUM_ID + '= ?', // File assets cannot be obtained based on the parent, albumId, albumUri, and albumName attributes.
      selectionArgs: [albumId.toString()],
    };
    const fetchFileResult = await media.getFileAssets(getImageOp); // The obtained fetchFileResult is empty.
    const fileAsset = await fetchFileResult.getFirstObject();
    console.info('mediaLibrary fileAsset displayName: ' + fileAsset.displayName);
  } catch (err) {
    console.error('mediaLibrary fail, err: ' + err);
  }
}

Use getFileAssets() as follows:

Example (correct):

import mediaLibrary from '@ohos.multimedia.mediaLibrary';

async function example() {
  try {
    let context = getContext(this);
    let media = mediaLibrary.getMediaLibrary(context);
    let fileKeyObj = mediaLibrary.FileKey;
    let imageType = mediaLibrary.MediaType.IMAGE;
    let getImageOp = {
      selections: fileKeyObj.MEDIA_TYPE + '= ?',
      selectionArgs: [imageType.toString()], // Query all files of the image type.
    };
    const fetchFileResult = await media.getFileAssets(getImageOp); 
    const fileAsset = await fetchFileResult.getFirstObject();
    console.info('mediaLibrary fileAsset displayName: ' + fileAsset.displayName);
  } catch (err) {
    console.error('mediaLibrary fail, err: ' + err);
  }
}

createAsset

Since the SDK of API version 10, relativePath is no longer associated with an album. After a file is created, the last-level directory of relativePath is not displayed as an album.

getAlbums

Since the SDK of API version 10, relativePath is no longer associated with an album. Therefore, relativePath cannot be used as a search criterion in getAlbums, and the values of ALBUM_NAME can be Camera and Screenshots only. The following is an example of incorrect use of the APIs.

1. Use getMediaLibrary to obtain a MediaLibrary instance.
2. Use MediaFetchOptions to create the album fetching options.
3. Use getAlbums to obtain albums.

Example (incorrect):

import mediaLibrary from '@ohos.multimedia.mediaLibrary';

async function example() {
  try {
    let context = getContext(this);
    let media = mediaLibrary.getMediaLibrary(context);
    let AlbumNoArgsfetchOp = {
      selections: mediaLibrary.FileKey.ALBUM_NAME + ' = ?',
      selectionArgs:['New album 1'], //Obtain the album named New album 1.
    };
    const albumList = await media.getAlbums(AlbumNoArgsfetchOp); // The fetchFileResult returned is empty.
    for (let i = 0; i < albumList.length; i++) {
      console.info('mediaLibrary album albumName: ' + albumList[i].albumName);
    }
  } catch (err) {
    console.error('mediaLibrary fail, err: ' + err);
  }
}

The following example shows how to obtain Camera and Screenshots albums:

Example (correct):

import mediaLibrary from '@ohos.multimedia.mediaLibrary';

async function example() {
  try {
    let context = getContext(this);
    let media = mediaLibrary.getMediaLibrary(context);
    let AlbumNoArgsfetchOp = {
      selections: mediaLibrary.FileKey.ALBUM_NAME + ' = ? OR ' + mediaLibrary.FileKey.ALBUM_NAME + ' = ?',
      selectionArgs: ['Camera', 'Screenshots'], // Obtain the camera and screenshot albums.
    };
    const albumList = await media.getAlbums(AlbumNoArgsfetchOp);
    for (let i = 0; i < albumList.length; i++) {
      console.info('mediaLibrary album albumName: ' + albumList[i].albumName);
    }
  } catch (err) {
    console.error('mediaLibrary fail, err: ' + err);
  }
}

FileAsset.commitModify

The orientation attribute for audio is deleted from the SDK of API version 10. When commitModify is used, the orientation attribute of audio resources cannot be modified.

FileAsset.deleteAsset

The change has resolved a known issue of the file deletion mechanism. This issue may cause a system application to permanently delete a file that is not in the trash using MediaLibrary.deleteAsset.

The correct procedure for a system application to permanently delete a file is as follows:

1. Call getFileAssets to obtain file assets.
2. Call FileAsset.trash to move the file to the trash.
3. Call MediaLibrary.deleteAsset to permanently delete the file.

Example (correct):

import mediaLibrary from '@ohos.multimedia.mediaLibrary';

async function example() {
  try {
    let context = getContext(this);
    let media = mediaLibrary.getMediaLibrary(context);
    let fileKeyObj = mediaLibrary.FileKey;
    let imageType = mediaLibrary.MediaType.IMAGE;
    let getImageOp = {
      selections: fileKeyObj.MEDIA_TYPE + '= ?',
      selectionArgs: [imageType.toString()],
    };
    const fetchFileResult = await media.getFileAssets(getImageOp); 
    const fileAsset = await fetchFileResult.getFirstObject();
    // Delete the file (move it to the trash of Gallery).
    await fileAsset.trash(true);
    // Delete the file from the system permanently.
    await media.deleteAsset(fileAsset.uri);
  } catch (err) {
    console.error('Failed to delete asset permanently from system, error: ' + err);
  }
}

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