/*
* Copyright 2010, 2011, 2012 mapsforge.org
*
* This program is free software: you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License as published by the Free Software
* Foundation, either version 3 of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
* PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.mapsforge.applications.android.advancedmapviewer.filepicker;
import java.io.File;
import java.io.FileFilter;
import java.util.Arrays;
import java.util.Comparator;
import org.mapsforge.applications.android.advancedmapviewer.R;
import org.mapsforge.applications.android.advancedmapviewer.filefilter.ValidFileFilter;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.view.View;
import android.view.WindowManager;
import android.widget.AdapterView;
import android.widget.GridView;
/**
* A FilePicker displays the contents of directories. The user can navigate within the file system and select a single
* file whose path is then returned to the calling activity. The ordering of directory contents can be specified via
* {@link #setFileComparator(Comparator)}. By default subfolders and files are grouped and each group is ordered
* alphabetically.
* <p>
* A {@link FileFilter} can be activated via {@link #setFileDisplayFilter(FileFilter)} to restrict the displayed files
* and folders. By default all files and folders are visible.
* <p>
* Another <code>FileFilter</code> can be applied via {@link #setFileSelectFilter(ValidFileFilter)} to check if a
* selected file is valid before its path is returned. By default all files are considered as valid and can be selected.
*/
public class FilePicker extends Activity implements AdapterView.OnItemClickListener {
/**
* The name of the extra data in the result {@link Intent}.
*/
public static final String SELECTED_FILE = "selectedFile";
private static final String CURRENT_DIRECTORY = "currentDirectory";
private static final String DEFAULT_DIRECTORY = "/";
private static final int DIALOG_FILE_INVALID = 0;
private static final int DIALOG_FILE_SELECT = 1;
private static Comparator<File> fileComparator = getDefaultFileComparator();
private static FileFilter fileDisplayFilter;
private static ValidFileFilter fileSelectFilter;
private static final String PREFERENCES_FILE = "FilePicker";
/**
* Sets the file comparator which is used to order the contents of all directories before displaying them. If set to
* null, subfolders and files will not be ordered.
*
* @param fileComparator
* the file comparator (may be null).
*/
public static void setFileComparator(Comparator<File> fileComparator) {
FilePicker.fileComparator = fileComparator;
}
/**
* Sets the file display filter. This filter is used to determine which files and subfolders of directories will be
* displayed. If set to null, all files and subfolders are shown.
*
* @param fileDisplayFilter
* the file display filter (may be null).
*/
public static void setFileDisplayFilter(FileFilter fileDisplayFilter) {
FilePicker.fileDisplayFilter = fileDisplayFilter;
}
/**
* Sets the file select filter. This filter is used when the user selects a file to determine if it is valid. If set
* to null, all files are considered as valid.
*
* @param fileSelectFilter
* the file selection filter (may be null).
*/
public static void setFileSelectFilter(ValidFileFilter fileSelectFilter) {
FilePicker.fileSelectFilter = fileSelectFilter;
}
/**
* Creates the default file comparator.
*
* @return the default file comparator.
*/
private static Comparator<File> getDefaultFileComparator() {
// order all files by type and alphabetically by name
return new Comparator<File>() {
@Override
public int compare(File file1, File file2) {
if (file1.isDirectory() && !file2.isDirectory()) {
return -1;
} else if (!file1.isDirectory() && file2.isDirectory()) {
return 1;
} else {
return file1.getName().compareToIgnoreCase(file2.getName());
}
}
};
}
private File currentDirectory;
private FilePickerIconAdapter filePickerIconAdapter;
private File[] files;
private File[] filesWithParentFolder;
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
File selectedFile = this.files[(int) id];
if (selectedFile.isDirectory()) {
this.currentDirectory = selectedFile;
browseToCurrentDirectory();
} else if (fileSelectFilter == null || fileSelectFilter.accept(selectedFile)) {
setResult(RESULT_OK, new Intent().putExtra(SELECTED_FILE, selectedFile.getAbsolutePath()));
finish();
} else {
showDialog(DIALOG_FILE_INVALID);
}
}
/**
* Browses to the current directory.
*/
private void browseToCurrentDirectory() {
setTitle(this.currentDirectory.getAbsolutePath());
// read the subfolders and files from the current directory
if (fileDisplayFilter == null) {
this.files = this.currentDirectory.listFiles();
} else {
this.files = this.currentDirectory.listFiles(fileDisplayFilter);
}
if (this.files == null) {
this.files = new File[0];
} else {
// order the subfolders and files
Arrays.sort(this.files, fileComparator);
}
// if a parent directory exists, add it at the first position
if (this.currentDirectory.getParentFile() != null) {
this.filesWithParentFolder = new File[this.files.length + 1];
this.filesWithParentFolder[0] = this.currentDirectory.getParentFile();
System.arraycopy(this.files, 0, this.filesWithParentFolder, 1, this.files.length);
this.files = this.filesWithParentFolder;
this.filePickerIconAdapter.setFiles(this.files, true);
} else {
this.filePickerIconAdapter.setFiles(this.files, false);
}
this.filePickerIconAdapter.notifyDataSetChanged();
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_file_picker);
this.filePickerIconAdapter = new FilePickerIconAdapter(this);
GridView gridView = (GridView) findViewById(R.id.filePickerView);
gridView.setOnItemClickListener(this);
gridView.setAdapter(this.filePickerIconAdapter);
if (savedInstanceState == null) {
// first start of this instance
showDialog(DIALOG_FILE_SELECT);
}
}
@Override
protected Dialog onCreateDialog(int id) {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
switch (id) {
case DIALOG_FILE_INVALID:
builder.setIcon(android.R.drawable.ic_menu_info_details);
builder.setTitle(R.string.error);
StringBuilder stringBuilder = new StringBuilder();
stringBuilder.append(getString(R.string.file_invalid));
stringBuilder.append("\n\n");
stringBuilder.append(FilePicker.fileSelectFilter.getFileOpenResult().getErrorMessage());
builder.setMessage(stringBuilder.toString());
builder.setPositiveButton(R.string.ok, null);
return builder.create();
case DIALOG_FILE_SELECT:
builder.setMessage(R.string.file_select);
builder.setPositiveButton(R.string.ok, null);
return builder.create();
default:
// do dialog will be created
return null;
}
}
@Override
protected void onPause() {
super.onPause();
// save the current directory
Editor editor = getSharedPreferences(PREFERENCES_FILE, MODE_PRIVATE).edit();
editor.clear();
if (this.currentDirectory != null) {
editor.putString(CURRENT_DIRECTORY, this.currentDirectory.getAbsolutePath());
}
editor.commit();
}
@Override
protected void onResume() {
super.onResume();
// check if the full screen mode should be activated
if (PreferenceManager.getDefaultSharedPreferences(this).getBoolean("fullscreen", false)) {
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
getWindow().clearFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN);
} else {
getWindow().clearFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN);
}
// restore the current directory
SharedPreferences preferences = getSharedPreferences(PREFERENCES_FILE, MODE_PRIVATE);
this.currentDirectory = new File(preferences.getString(CURRENT_DIRECTORY, DEFAULT_DIRECTORY));
if (!this.currentDirectory.exists() || !this.currentDirectory.canRead()) {
this.currentDirectory = new File(DEFAULT_DIRECTORY);
}
browseToCurrentDirectory();
}
}