patheditor.java

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/*******************************************************************************
 * Copyright (c) 2000, 2006 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jface.preference;

import java.io.File;
import java.util.ArrayList;
import java.util.StringTokenizer;

import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.DirectoryDialog;

/**
 * A field editor to edit directory paths.
 */
public class PathEditor extends ListEditor {

    /**
     * The last path, or <code>null</code> if none.
     */
    private String lastPath;

    /**
     * The special label text for directory chooser, 
     * or <code>null</code> if none.
     */
    private String dirChooserLabelText;

    /**
     * Creates a new path field editor 
     */
    protected PathEditor() {
    }

    /**
     * Creates a path field editor.
     * 
     * @param name the name of the preference this field editor works on
     * @param labelText the label text of the field editor
     * @param dirChooserLabelText the label text displayed for the directory chooser
     * @param parent the parent of the field editor's control
     */
    public PathEditor(String name, String labelText,
            String dirChooserLabelText, Composite parent) {
        init(name, labelText);
        this.dirChooserLabelText = dirChooserLabelText;
        createControl(parent);
    }

    /* (non-Javadoc)
     * Method declared on ListEditor.
     * Creates a single string from the given array by separating each
     * string with the appropriate OS-specific path separator.
     */
    protected String createList(String[] items) {
        StringBuffer path = new StringBuffer("");//$NON-NLS-1$

        for (int i = 0; i < items.length; i++) {
            path.append(items[i]);
            path.append(File.pathSeparator);
        }
        return path.toString();
    }

    /* (non-Javadoc)
     * Method declared on ListEditor.
     * Creates a new path element by means of a directory dialog.
     */
    protected String getNewInputObject() {

        DirectoryDialog dialog = new DirectoryDialog(getShell());
        if (dirChooserLabelText != null) {
			dialog.setMessage(dirChooserLabelText);
		}
        if (lastPath != null) {
            if (new File(lastPath).exists()) {
				dialog.setFilterPath(lastPath);
			}
        }
        String dir = dialog.open();
        if (dir != null) {
            dir = dir.trim();
            if (dir.length() == 0) {
				return null;
			}
            lastPath = dir;
        }
        return dir;
    }

    /* (non-Javadoc)
     * Method declared on ListEditor.
     */
    protected String[] parseString(String stringList) {
        StringTokenizer st = new StringTokenizer(stringList, File.pathSeparator
                + "\n\r");//$NON-NLS-1$
        ArrayList v = new ArrayList();
        while (st.hasMoreElements()) {
            v.add(st.nextElement());
        }
        return (String[]) v.toArray(new String[v.size()]);
    }
}