存储访问框架 - 在ACTION_OPEN_DOCUMENT文件选择器中显示特定文件

Question

我正在使用Storage Access Framework删除特定文件。我已经知道用户想删除哪个特定文件。有没有办法在文件选择器中向用户显示此特定文件？目前，它始终从根目录打开，然后用户必须导航到该文件。这是一个可用性问题。

或者，有没有办法只是请求所需的权限？

Answer 1

这对我有用。

package com.test.filedialog.file;

import java.io.File;
import java.io.FilenameFilter;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.content.DialogInterface;
import android.os.Environment;
import android.util.Log;
import com.test.filedialog.file.ListenerList.FireHandler;

public class FileDialog {
    private static final String PARENT_DIR = "..";
    private final String TAG = getClass().getName();
    private String[] fileList;
    private File currentPath;

    public interface FileSelectedListener {
        void fileSelected(File file);
    }

    public interface DirectorySelectedListener {
        void directorySelected(File directory);
    }

    private ListenerList<FileSelectedListener> fileListenerList = new ListenerList<FileSelectedListener>();
    private ListenerList<DirectorySelectedListener> dirListenerList = new ListenerList<DirectorySelectedListener>();
    private final Activity activity;
    private boolean selectDirectoryOption;
    private String fileEndsWith;
    private String[] fileEndsWiths;   

    /**
     * @param activity 
     * @param initialPath - HERE IS WHERE YOU SHOULD GIVE THE DIRECTORY YOU WANT
     */
    public FileDialog(Activity activity, File initialPath) {
        this.activity = activity;
        if (!path.exists()) path = Environment.getExternalStorageDirectory();
        loadFileList(path);
    }

    /**
     * @return file dialog
     */
    public Dialog createFileDialog() {
        Dialog dialog = null;
        AlertDialog.Builder builder = new AlertDialog.Builder(activity);

        builder.setTitle(currentPath.getPath());
        if (selectDirectoryOption) {
            builder.setPositiveButton("Select directory", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int which) {
                    Log.d(TAG, currentPath.getPath());
                    fireDirectorySelectedEvent(currentPath);
                }
            });
        }

        builder.setItems(fileList, new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int which) {
                String fileChosen = fileList[which];
                File chosenFile = getChosenFile(fileChosen);
                if (chosenFile.isDirectory()) {
                    loadFileList(chosenFile);
                    dialog.cancel();
                    dialog.dismiss();
                    showDialog();
                } else fireFileSelectedEvent(chosenFile);
            }
        });

        dialog = builder.show();
        return dialog;
    }    

    public void addFileListener(FileSelectedListener listener) {
        fileListenerList.add(listener);
    }

    public void removeFileListener(FileSelectedListener listener) {
        fileListenerList.remove(listener);
    }

    public void setSelectDirectoryOption(boolean selectDirectoryOption) {
        this.selectDirectoryOption = selectDirectoryOption;
    }

    public void addDirectoryListener(DirectorySelectedListener listener) {
        dirListenerList.add(listener);
    }

    public void removeDirectoryListener(DirectorySelectedListener listener) {
        dirListenerList.remove(listener);
    }

    /**
     * Show file dialog
     */
    public void showDialog() {
        createFileDialog().show();
    }

    private void fireFileSelectedEvent(final File file) {
        fileListenerList.fireEvent(new FireHandler<FileSelectedListener>() {
            public void fireEvent(FileSelectedListener listener) {
                listener.fileSelected(file);
            }
        });
    }

    private void fireDirectorySelectedEvent(final File directory) {
        dirListenerList.fireEvent(new FireHandler<DirectorySelectedListener>() {
            public void fireEvent(DirectorySelectedListener listener) {
                listener.directorySelected(directory);
            }
        });
    }

    private void loadFileList(File path) {
        this.currentPath = path;
        List<String> r = new ArrayList<String>();
        if (path.exists()) {
            if (path.getParentFile() != null) r.add(PARENT_DIR);
            @SuppressWarnings("unused")
            FilenameFilter filter = new FilenameFilter() {
                public boolean accept(File dir, String filename) {
                    File sel = new File(dir, filename);

                    if (!sel.canRead()) return false;
                    if (selectDirectoryOption) return sel.isDirectory();
                    else {
                        boolean endsWith = false;
                        if(fileEndsWiths != null){
                            System.out.println("File Input Lengths : " + fileEndsWiths.length);
                            for(int i = 0; i < fileEndsWiths.length; i++){
                                endsWith = fileEndsWiths[i] != null ? filename.toLowerCase(Locale.getDefault()).endsWith(fileEndsWiths[i]) : true;
                            }
                        }
                        else{
                            endsWith = fileEndsWith != null ? filename.toLowerCase(Locale.getDefault()).endsWith(fileEndsWith) : true;
                            System.out.println("No Files");
                        }                       

                        return endsWith || sel.isDirectory();
                    }
                }
            };
//            String[] fileList1 = path.list(filter);
            File[] fileList1 = path.listFiles();
            for (File file : fileList1) {
                r.add(file.getName());
            }
        }
        fileList = (String[]) r.toArray(new String[]{});
    }

    private File getChosenFile(String fileChosen) {
        if (fileChosen.equals(PARENT_DIR)) return currentPath.getParentFile();
        else return new File(currentPath, fileChosen);
    }

    public void setFileEndsWith(String[] fileEndsWith) {
        this.fileEndsWiths = fileEndsWith;
    }

    public void setFileEndsWith(String fileEndsWith) {
        this.fileEndsWith = fileEndsWith != null ? fileEndsWith.toLowerCase(Locale.getDefault()) : fileEndsWith;
    }
 }

class ListenerList<L> {
    private List<L> listenerList = new ArrayList<L>();

    public interface FireHandler<L> {
        void fireEvent(L listener);
    }

    public void add(L listener) {
        listenerList.add(listener);
    }

    public void fireEvent(FireHandler<L> fireHandler) {
        List<L> copy = new ArrayList<L>(listenerList);
        for (L l : copy) {
            fireHandler.fireEvent(l);
        }
    }

    public void remove(L listener) {
        listenerList.remove(listener);
    }

    public List<L> getListenerList() {
        return listenerList;
    }
}

要浏览和接收所选文件，请使用以下内容。

private void browseFiles(){
    File mPath = new File(Environment.getExternalStorageDirectory() + "//DIR//");
    FileDialog fileDialog = new FileDialog(getActivity(), mPath);
    /**
     * Specify the file type here
     * **/
    String[] fileTypes = new String[] { ".png", ".jpg", ".jpeg", ".PNG", ".JPG", ".JPEG", ".gif", ".GIF", ".tif", ".TIF"};
    //This fileTypes Array is optional
    fileDialog.setFileEndsWith(fileTypes);
    fileDialog.setFileEndsWith(".png");

    fileDialog.addFileListener(new FileDialog.FileSelectedListener() {
        public void fileSelected(File file) {
            //file is the selected File
        }
    });

    fileDialog.showDialog();
}