Question

我想知道如何确定文件路径是来自内部存储还是外部存储。

我要删除文件。在删除它之前，我想检查它是来自内部存储器还是外部存储器。如果文件来自内部存储，那么我可以像这样

$ unzip -l test3.zip
Archive:  test.zip
  Length      Date    Time    Name
---------  ---------- -----   ----
        0  2019-11-08 16:51   file1
        0  2019-11-08 16:51   file2
        0  2019-11-08 16:51   file3
        0  2019-11-08 16:52   file4
        0  2019-11-08 16:53   file5
---------                     -------
        0                     5 files

但是如果文件来自外部存储（sdcard）。然后我先检查权限，然后通过存储访问框架将其删除。

我目前正在这样做。

file.delete();

deleteFileWithSAF（）

            File selectedFile = Constant.allMemoryVideoList.get(fPosition).getFile().getAbsoluteFile();

            if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                if (???????????? check if file is not from internal storage ???????????) {
                    List<UriPermission> permissions = getContentResolver().getPersistedUriPermissions();
                    if (permissions != null && permissions.size() > 0) {
                        sdCardUri = permissions.get(0).getUri();
                        deleteFileWithSAF();
                    } else {
                        AlertDialog.Builder builder = new AlertDialog.Builder(this);
                        builder.setTitle("Please select external storage directory (e.g SDCard)")
                                .setMessage("Due to change in android security policy it is not possible to delete or rename file in external storage without granting permission")
                                .setPositiveButton("OK", new DialogInterface.OnClickListener() {
                                    @Override
                                    public void onClick(DialogInterface dialog, int which) {
                                        // call document tree dialog
                                        Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT_TREE);
                                        startActivityForResult(intent, REQUEST_CODE_OPEN_DOCUMENT_TREE);
                                    }
                                })
                                .setNegativeButton("CANCEL", new DialogInterface.OnClickListener() {
                                    @Override
                                    public void onClick(DialogInterface dialog, int which) {

                                    }
                                })
                                .show();
                    }

                } else {
                    deleteFile();
                }
            } else {
                deleteFile();
            }

这是我加载内部和外部存储文件的方式。

StorageUtil是库https://github.com/hendrawd/StorageUtil

    private void deleteFileWithSAF() {
        //First we get `DocumentFile` from the `TreeUri` which in our case is `sdCardUri`.
        DocumentFile documentFile = DocumentFile.fromTreeUri(this, sdCardUri);

        //Then we split file path into array of strings.
        //ex: parts:{"", "storage", "extSdCard", "MyFolder", "MyFolder", "myImage.jpg"}
        // There is a reason for having two similar names "MyFolder" in
        //my exmple file path to show you similarity in names in a path will not
        //distract our hiarchy search that is provided below.
        String[] parts = (selectedFile.getPath()).split("\\/");

        // findFile method will search documentFile for the first file
        // with the expected `DisplayName`

        // We skip first three items because we are already on it.(sdCardUri = /storage/extSdCard)
        for (int i = 3; i < parts.length; i++) {
            if (documentFile != null) {
                documentFile = documentFile.findFile(parts[i]);
            }
        }

        if (documentFile == null) {

            // File not found on tree search
            // User selected a wrong directory as the sd-card
            // Here must inform user about how to get the correct sd-card
            // and invoke file chooser dialog again.

            AlertDialog.Builder builder = new AlertDialog.Builder(this);
            builder.setTitle("Please select root of external storage directory (click SELECT button at bottom)")
                    .setMessage("Due to change in android security policy it is not possible to delete or rename file in external storage without granting permission")
                    .setPositiveButton("OK", new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialog, int which) {
                            // call for document tree dialog
                            Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT_TREE);
                            startActivityForResult(intent, REQUEST_CODE_OPEN_DOCUMENT_TREE);
                        }
                    })
                    .setNegativeButton("CANCEL", new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialog, int which) {

                        }
                    })
                    .show();

        } else {

            // File found on sd-card and it is a correct sd-card directory
            // save this path as a root for sd-card on your database(SQLite, XML, txt,...)

            // Now do whatever you like to do with documentFile.
            // Here I do deletion to provide an example.


            if (documentFile.delete()) {// if delete file succeed
                // Remove information related to your media from ContentResolver,
                // which documentFile.delete() didn't do the trick for me.
                // Must do it otherwise you will end up with showing an empty
                // ImageView if you are getting your URLs from MediaStore.


                getApplicationContext().sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, Uri.fromFile(selectedFile)));
//                              Methods.removeMedia(this,selectedFile.getPath());

                if (deleteSingleFileCall){
                    Constant.allMemoryVideoList.remove(videoPosition);
                    adapter.notifyItemRemoved(videoPosition);
                    deleteSingleFileCall = false;
                }

                /*update the playback record to
                 * getFileName() contain file.getName()*/
                for (int i = 0; i < Constant.filesPlaybackHistory.size(); i++) {
                    if ((selectedFile.getName()).equals(Constant.filesPlaybackHistory.get(i).getFileName())) {
                        Constant.filesPlaybackHistory.remove(i);
                        break;
                    }
                }

                //save the playback history
                Paper.book().write("playbackHistory", Constant.filesPlaybackHistory);

            }
        }
    }

以下数组列表中的所有已加载文件。

String[] allPath = StorageUtil.getStorageDirectories(this);
private File directory;
for (String path: allPath){
    directory = new File(path);
    Methods.load_Directory_Files(directory);
}

FilesInfo：包含有关文件的所有信息，例如缩略图，时长，目录，新建或以前播放过的文件（如果播放过则是最后播放位置等）

LoadDirectoryFiles（）

//all the directory that contains files
public static ArrayList<File> directoryList = null;
//list of all files (internal and external)
public static ArrayList<FilesInfo> allMemoryVideoList = new ArrayList<>();

图片，以便读者可以轻松了解正在发生的事情。

如何知道文件来自android的内部或外部存储？

0 个答案: