Android file choose dialog again

steveh picture steveh · Apr 3, 2013 · Viewed 7.5k times · Source

i have exactly the same question as this post Choose File Dialog

i didn't see any really usable answers in there.

ideally i would like a simple java code example of a simple dialog that works like MFC CFileDialog Class, i.e. you simply new it, do a .show and it works

everything i've seen so far looks overly complicated for what should be a very simple job. can anyone help with more up to date info?

thanks

UPDATE,

in that post Choose File Dialog the answer by Kirill Mikhailov seems to work fine after a few mins testing

Answer

steveh picture steveh · Apr 4, 2013

i added a cancel button to that example, seems to work fine

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

import com.design2112.tabtrax.ListenerList.FireHandler;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.content.DialogInterface;
import android.os.Environment;

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<FileDialog.FileSelectedListener>();
    private ListenerList<DirectorySelectedListener> dirListenerList = new ListenerList<FileDialog.DirectorySelectedListener>();
    private final Activity activity;
    private boolean selectDirectoryOption;
    private String fileEndsWith;

    /**
     * @param activity
     * @param initialPath
     */
    public FileDialog(Activity activity, String path) {
        this.activity = activity; 
        loadFileList(new File(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 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);
            }
        });
        builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int which) { 
                dialog.dismiss();
            }
        });
        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<FileDialog.FileSelectedListener>() {
            public void fireEvent(FileSelectedListener listener) {
                listener.fileSelected(file);
            }
        });
    }

    private void fireDirectorySelectedEvent(final File directory) {
        dirListenerList.fireEvent(new FireHandler<FileDialog.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);
            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 = fileEndsWith != null ? filename
                                .toLowerCase().endsWith(fileEndsWith) : true;
                        return endsWith || sel.isDirectory();
                    }
                }
            };
            String[] fileList1 = path.list(filter);
            for (String file : fileList1) {
                r.add(file);
            }
        }
        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.fileEndsWith = fileEndsWith != null ? fileEndsWith.toLowerCase()
                : 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;
    }
}