org.eclipse.swt.widgets.DirectoryDialog.java Source code

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/*******************************************************************************
 * Copyright (c) 2000, 2019 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.swt.widgets;

import java.io.*;

import org.eclipse.swt.*;
import org.eclipse.swt.internal.*;
import org.eclipse.swt.internal.gtk.*;

/**
 * Instances of this class allow the user to navigate
 * the file system and select a directory.
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>(none)</dd>
 * <dt><b>Events:</b></dt>
 * <dd>(none)</dd>
 * </dl>
 * <p>
 * IMPORTANT: This class is <em>not</em> intended to be subclassed.
 * </p>
 *
 * @see <a href="http://www.eclipse.org/swt/snippets/#directorydialog">DirectoryDialog snippets</a>
 * @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example: ControlExample, Dialog tab</a>
 * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
 * @noextend This class is not intended to be subclassed by clients.
 */
public class DirectoryDialog extends Dialog {
    String message = "", filterPath = "";
    static final String SEPARATOR = File.separator;

    /**
     * Constructs a new instance of this class given only its parent.
     *
     * @param parent a shell which will be the parent of the new instance
     *
     * @exception IllegalArgumentException <ul>
     *    <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
     * </ul>
     * @exception SWTException <ul>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li>
     *    <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li>
     * </ul>
     */
    public DirectoryDialog(Shell parent) {
        this(parent, SWT.APPLICATION_MODAL);
    }

    /**
     * Constructs a new instance of this class given its parent
     * and a style value describing its behavior and appearance.
     * <p>
     * The style value is either one of the style constants defined in
     * class <code>SWT</code> which is applicable to instances of this
     * class, or must be built by <em>bitwise OR</em>'ing together
     * (that is, using the <code>int</code> "|" operator) two or more
     * of those <code>SWT</code> style constants. The class description
     * lists the style constants that are applicable to the class.
     * Style bits are also inherited from superclasses.
     * </p>
     *
     * @param parent a shell which will be the parent of the new instance
     * @param style the style of dialog to construct
     *
     * @exception IllegalArgumentException <ul>
     *    <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
     * </ul>
     * @exception SWTException <ul>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li>
     *    <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li>
     * </ul>
     */
    public DirectoryDialog(Shell parent, int style) {
        super(parent, checkStyle(parent, style));
        checkSubclass();
    }

    /**
     * Returns the path which the dialog will use to filter
     * the directories it shows.
     *
     * @return the filter path
     *
     * @see #setFilterPath
     */
    public String getFilterPath() {
        return filterPath;
    }

    /**
     * Returns the dialog's message, which is a description of
     * the purpose for which it was opened. This message will be
     * visible on the dialog while it is open.
     *
     * @return the message
     */
    public String getMessage() {
        return message;
    }

    /**
     * Makes the dialog visible and brings it to the front
     * of the display.
     *
     * @return a string describing the absolute path of the selected directory,
     *         or null if the dialog was cancelled or an error occurred
     *
     * @exception SWTException <ul>
     *    <li>ERROR_WIDGET_DISPOSED - if the dialog has been disposed</li>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the dialog</li>
     * </ul>
     */
    public String open() {
        if (GTK.GTK_VERSION >= OS.VERSION(3, 20, 0)) {
            return openNativeChooserDialog();
        } else {
            return openChooserDialog();
        }
    }

    /**
     * Open the file chooser dialog using the GtkFileChooserNative API (GTK3.20+) for running applications
     * without direct filesystem access (such as Flatpak). API for GtkFileChoosernative does not
     * give access to any GtkWindow or GtkWidget for the dialog, thus this method omits calls that
     * requires such access. These are be handled by the GtkNativeDialog API.
     *
     * @return a string describing the absolute path of the first selected file, or null
     */
    String openNativeChooserDialog() {
        byte[] titleBytes = Converter.wcsToMbcs(title, true);
        long shellHandle = parent.topHandle();
        Display display = parent != null ? parent.getDisplay() : Display.getCurrent();
        long handle = 0;
        handle = GTK.gtk_file_chooser_native_new(titleBytes, shellHandle, GTK.GTK_FILE_CHOOSER_ACTION_SELECT_FOLDER,
                null, null);
        if (handle == 0)
            error(SWT.ERROR_NO_HANDLES);

        if (filterPath != null && filterPath.length() > 0) {
            StringBuilder stringBuilder = new StringBuilder();
            /* filename must be a full path */
            if (!filterPath.startsWith(SEPARATOR)) {
                stringBuilder.append(SEPARATOR);
            }
            stringBuilder.append(filterPath);
            byte[] buffer = Converter.wcsToMbcs(stringBuilder.toString(), true);
            /*
             * in GTK version 2.10, gtk_file_chooser_set_current_folder requires path
             * to be true canonical path. So using realpath to convert the path to
             * true canonical path.
             */
            long ptr = OS.realpath(buffer, null);
            if (ptr != 0) {
                GTK.gtk_file_chooser_set_current_folder(handle, ptr);
                OS.g_free(ptr);
            }
        }
        if (message.length() > 0) {
            byte[] buffer = Converter.wcsToMbcs(message, true);
            long box = GTK.gtk_box_new(GTK.GTK_ORIENTATION_HORIZONTAL, 0);
            GTK.gtk_box_set_homogeneous(box, false);
            if (box == 0)
                error(SWT.ERROR_NO_HANDLES);
            long label = GTK.gtk_label_new(buffer);
            if (label == 0)
                error(SWT.ERROR_NO_HANDLES);
            GTK.gtk_container_add(box, label);
            GTK.gtk_widget_show(label);
            GTK.gtk_label_set_line_wrap(label, true);
            GTK.gtk_label_set_justify(label, GTK.GTK_JUSTIFY_CENTER);
            GTK.gtk_file_chooser_set_extra_widget(handle, box);
        }
        String answer = null;
        display.addIdleProc();
        int signalId = 0;
        long hookId = 0;
        if ((style & SWT.RIGHT_TO_LEFT) != 0) {
            signalId = OS.g_signal_lookup(OS.map, GTK.GTK_TYPE_WIDGET());
            hookId = OS.g_signal_add_emission_hook(signalId, 0, display.emissionProc, handle, 0);
        }
        display.sendPreExternalEventDispatchEvent();
        int response = GTK.gtk_native_dialog_run(handle);
        /*
        * This call to gdk_threads_leave() is a temporary work around
        * to avoid deadlocks when gdk_threads_init() is called by native
        * code outside of SWT (i.e AWT, etc). It ensures that the current
        * thread leaves the GTK lock acquired by the function above.
        */
        if (!GTK.GTK4)
            GDK.gdk_threads_leave();
        display.sendPostExternalEventDispatchEvent();
        if ((style & SWT.RIGHT_TO_LEFT) != 0) {
            OS.g_signal_remove_emission_hook(signalId, hookId);
        }
        if (response == GTK.GTK_RESPONSE_ACCEPT) {
            long path = GTK.gtk_file_chooser_get_filename(handle);
            if (path != 0) {
                long utf8Ptr = OS.g_filename_to_utf8(path, -1, null, null, null);
                if (utf8Ptr == 0)
                    utf8Ptr = OS.g_filename_display_name(path);
                if (path != utf8Ptr)
                    OS.g_free(path);
                if (utf8Ptr != 0) {
                    long[] items_written = new long[1];
                    long utf16Ptr = OS.g_utf8_to_utf16(utf8Ptr, -1, null, items_written, null);
                    OS.g_free(utf8Ptr);
                    if (utf16Ptr != 0) {
                        int clength = (int) items_written[0];
                        char[] chars = new char[clength];
                        C.memmove(chars, utf16Ptr, clength * 2);
                        OS.g_free(utf16Ptr);
                        answer = new String(chars);
                        filterPath = answer;
                    }
                }
            }
        }
        display.removeIdleProc();
        return answer;
    }

    String openChooserDialog() {
        byte[] titleBytes = Converter.wcsToMbcs(title, true);
        long shellHandle = parent.topHandle();
        Display display = parent != null ? parent.getDisplay() : Display.getCurrent();
        long handle = 0;
        if (display.getDismissalAlignment() == SWT.RIGHT) {
            handle = GTK.gtk_file_chooser_dialog_new(titleBytes, shellHandle,
                    GTK.GTK_FILE_CHOOSER_ACTION_SELECT_FOLDER, GTK.GTK_NAMED_LABEL_CANCEL, GTK.GTK_RESPONSE_CANCEL,
                    GTK.GTK_NAMED_LABEL_OK, GTK.GTK_RESPONSE_OK, 0);
        } else {
            handle = GTK.gtk_file_chooser_dialog_new(titleBytes, shellHandle,
                    GTK.GTK_FILE_CHOOSER_ACTION_SELECT_FOLDER, GTK.GTK_NAMED_LABEL_OK, GTK.GTK_RESPONSE_OK,
                    GTK.GTK_NAMED_LABEL_CANCEL, GTK.GTK_RESPONSE_CANCEL, 0);
        }
        if (handle == 0)
            error(SWT.ERROR_NO_HANDLES);
        long group = GTK.gtk_window_get_group(0);
        GTK.gtk_window_group_add_window(group, handle);
        GTK.gtk_window_set_modal(handle, true);
        long pixbufs = GTK.gtk_window_get_icon_list(shellHandle);
        if (pixbufs != 0) {
            GTK.gtk_window_set_icon_list(handle, pixbufs);
            OS.g_list_free(pixbufs);
        }
        if (filterPath != null && filterPath.length() > 0) {
            StringBuilder stringBuilder = new StringBuilder();
            /* filename must be a full path */
            if (!filterPath.startsWith(SEPARATOR)) {
                stringBuilder.append(SEPARATOR);
            }
            stringBuilder.append(filterPath);
            byte[] buffer = Converter.wcsToMbcs(stringBuilder.toString(), true);
            /*
             * in GTK version 2.10, gtk_file_chooser_set_current_folder requires path
             * to be true canonical path. So using realpath to convert the path to
             * true canonical path.
             */
            long ptr = OS.realpath(buffer, null);
            if (ptr != 0) {
                GTK.gtk_file_chooser_set_current_folder(handle, ptr);
                OS.g_free(ptr);
            }
        }
        if (message.length() > 0) {
            byte[] buffer = Converter.wcsToMbcs(message, true);
            long box = GTK.gtk_box_new(GTK.GTK_ORIENTATION_HORIZONTAL, 0);
            GTK.gtk_box_set_homogeneous(box, false);
            if (box == 0)
                error(SWT.ERROR_NO_HANDLES);
            long label = GTK.gtk_label_new(buffer);
            if (label == 0)
                error(SWT.ERROR_NO_HANDLES);
            GTK.gtk_container_add(box, label);
            GTK.gtk_widget_show(label);
            GTK.gtk_label_set_line_wrap(label, true);
            GTK.gtk_label_set_justify(label, GTK.GTK_JUSTIFY_CENTER);
            GTK.gtk_file_chooser_set_extra_widget(handle, box);
        }
        String answer = null;
        display.addIdleProc();
        Dialog oldModal = null;
        if (GTK.gtk_window_get_modal(handle)) {
            oldModal = display.getModalDialog();
            display.setModalDialog(this);
        }
        int signalId = 0;
        long hookId = 0;
        if ((style & SWT.RIGHT_TO_LEFT) != 0) {
            signalId = OS.g_signal_lookup(OS.map, GTK.GTK_TYPE_WIDGET());
            hookId = OS.g_signal_add_emission_hook(signalId, 0, display.emissionProc, handle, 0);
        }
        display.sendPreExternalEventDispatchEvent();
        int response = GTK.gtk_dialog_run(handle);
        /*
        * This call to gdk_threads_leave() is a temporary work around
        * to avoid deadlocks when gdk_threads_init() is called by native
        * code outside of SWT (i.e AWT, etc). It ensures that the current
        * thread leaves the GTK lock acquired by the function above.
        */
        if (!GTK.GTK4)
            GDK.gdk_threads_leave();
        display.sendPostExternalEventDispatchEvent();
        if ((style & SWT.RIGHT_TO_LEFT) != 0) {
            OS.g_signal_remove_emission_hook(signalId, hookId);
        }
        if (GTK.gtk_window_get_modal(handle)) {
            display.setModalDialog(oldModal);
        }
        if (response == GTK.GTK_RESPONSE_OK) {
            long path = GTK.gtk_file_chooser_get_filename(handle);
            if (path != 0) {
                long utf8Ptr = OS.g_filename_to_utf8(path, -1, null, null, null);
                if (utf8Ptr == 0)
                    utf8Ptr = OS.g_filename_display_name(path);
                if (path != utf8Ptr)
                    OS.g_free(path);
                if (utf8Ptr != 0) {
                    long[] items_written = new long[1];
                    long utf16Ptr = OS.g_utf8_to_utf16(utf8Ptr, -1, null, items_written, null);
                    OS.g_free(utf8Ptr);
                    if (utf16Ptr != 0) {
                        int clength = (int) items_written[0];
                        char[] chars = new char[clength];
                        C.memmove(chars, utf16Ptr, clength * 2);
                        OS.g_free(utf16Ptr);
                        answer = new String(chars);
                        filterPath = answer;
                    }
                }
            }
        }
        display.removeIdleProc();
        GTK.gtk_widget_destroy(handle);
        return answer;
    }

    /**
     * Sets the path that the dialog will use to filter
     * the directories it shows to the argument, which may
     * be null. If the string is null, then the operating
     * system's default filter path will be used.
     * <p>
     * Note that the path string is platform dependent.
     * For convenience, either '/' or '\' can be used
     * as a path separator.
     * </p>
     *
     * @param string the filter path
     */
    public void setFilterPath(String string) {
        filterPath = string;
    }

    /**
     * Sets the dialog's message, which is a description of
     * the purpose for which it was opened. This message will be
     * visible on the dialog while it is open.
     * <p>
     * NOTE: This operation is a hint and is not supported on some platforms. For
     * example, on Windows (Vista and later), the <code>DirectoryDialog</code>
     * doesn't have any provision to set a message.
     * </p>
     *
     * @param string the message
     *
     * @exception IllegalArgumentException <ul>
     *    <li>ERROR_NULL_ARGUMENT - if the string is null</li>
     * </ul>
     */
    public void setMessage(String string) {
        if (string == null)
            error(SWT.ERROR_NULL_ARGUMENT);
        message = string;
    }
}