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

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/*******************************************************************************
 * Copyright (c) 2000, 2017 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 org.eclipse.swt.*;
import org.eclipse.swt.events.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.internal.win32.*;

/**
 * Instances of this class represent icons that can be placed on the
 * system tray or task bar status area.
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>(none)</dd>
 * <dt><b>Events:</b></dt>
 * <dd>DefaultSelection, MenuDetect, Selection</dd>
 * </dl>
 * <p>
 * IMPORTANT: This class is <em>not</em> intended to be subclassed.
 * </p>
 *
 * @see <a href="http://www.eclipse.org/swt/snippets/#tray">Tray, TrayItem snippets</a>
 * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
 *
 * @since 3.0
 * @noextend This class is not intended to be subclassed by clients.
 */
public class TrayItem extends Item {
    Tray parent;
    int id;
    Image image2, highlightImage;
    ToolTip toolTip;
    String toolTipText;
    boolean visible = true;

    /**
     * Constructs a new instance of this class given its parent
     * (which must be a <code>Tray</code>) and a style value
     * describing its behavior and appearance. The item is added
     * to the end of the items maintained by its parent.
     * <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 composite control which will be the parent of the new instance (cannot be null)
     * @param style the style of control 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>
     *
     * @see SWT
     * @see Widget#checkSubclass
     * @see Widget#getStyle
     */
    public TrayItem(Tray parent, int style) {
        super(parent, style);
        this.parent = parent;
        parent.createItem(this, parent.getItemCount());
        createUpdateWidget(true);
    }

    /**
     * Adds the listener to the collection of listeners who will
     * be notified when the receiver is selected by the user, by sending
     * it one of the messages defined in the <code>SelectionListener</code>
     * interface.
     * <p>
     * <code>widgetSelected</code> is called when the receiver is selected
     * <code>widgetDefaultSelected</code> is called when the receiver is double-clicked
     * </p>
     *
     * @param listener the listener which should be notified when the receiver is selected by the user
     *
     * @exception IllegalArgumentException <ul>
     *    <li>ERROR_NULL_ARGUMENT - if the listener is null</li>
     * </ul>
     * @exception SWTException <ul>
     *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
     * </ul>
     *
     * @see SelectionListener
     * @see #removeSelectionListener
     * @see SelectionEvent
     */
    public void addSelectionListener(SelectionListener listener) {
        checkWidget();
        if (listener == null)
            error(SWT.ERROR_NULL_ARGUMENT);
        TypedListener typedListener = new TypedListener(listener);
        addListener(SWT.Selection, typedListener);
        addListener(SWT.DefaultSelection, typedListener);
    }

    /**
     * Adds the listener to the collection of listeners who will
     * be notified when the platform-specific context menu trigger
     * has occurred, by sending it one of the messages defined in
     * the <code>MenuDetectListener</code> interface.
     *
     * @param listener the listener which should be notified
     *
     * @exception IllegalArgumentException <ul>
     *    <li>ERROR_NULL_ARGUMENT - if the listener is null</li>
     * </ul>
     * @exception SWTException <ul>
     *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
     * </ul>
     *
     * @see MenuDetectListener
     * @see #removeMenuDetectListener
     *
     * @since 3.3
     */
    public void addMenuDetectListener(MenuDetectListener listener) {
        checkWidget();
        if (listener == null)
            error(SWT.ERROR_NULL_ARGUMENT);
        TypedListener typedListener = new TypedListener(listener);
        addListener(SWT.MenuDetect, typedListener);
    }

    @Override
    protected void checkSubclass() {
        if (!isValidSubclass())
            error(SWT.ERROR_INVALID_SUBCLASS);
    }

    void createUpdateWidget(boolean newIcon) {
        NOTIFYICONDATA iconData = new NOTIFYICONDATA();
        iconData.cbSize = NOTIFYICONDATA.sizeof;
        /*
         * As per MSDN article iconData.uID is unique for every TrayItem
         * instance(https://msdn.microsoft.com/en-us/library/windows/desktop/
         * bb762159%28v=vs.85%29.aspx) and this uID value should be specified
         * during TrayItem instance creation & should be cached and used in
         * subsequent calls to Shell_NotifyIcon to perform later actions on the
         * TrayItem instance refer Win10 bug 488739.
         */
        iconData.uID = id = (newIcon ? display.nextTrayId++ : id);
        iconData.hWnd = display.hwndMessage;
        iconData.uFlags = OS.NIF_MESSAGE;
        iconData.uCallbackMessage = Display.SWT_TRAYICONMSG;
        /*
         * OS.NIM_ADD message should be called only once in a TrayItem instance
         * life-cycle i.e. in the TrayItem instance creation step only, else
         * will lead to multiple TrayIcons entries on Win10 refer bug 488739.
         */
        OS.Shell_NotifyIcon((newIcon ? OS.NIM_ADD : OS.NIM_MODIFY), iconData);
    }

    @Override
    void destroyWidget() {
        parent.destroyItem(this);
        releaseHandle();
    }

    /**
     * Returns the receiver's highlight image if it has one, or null
     * if it does not.
     *
     * @return the receiver's highlight image
     *
     * @exception SWTException <ul>
     *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
     * </ul>
     *
     * @since 3.8
     */
    public Image getHighlightImage() {
        checkWidget();
        return highlightImage;
    }

    /**
     * Returns the receiver's parent, which must be a <code>Tray</code>.
     *
     * @return the receiver's parent
     *
     * @exception SWTException <ul>
     *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
     * </ul>
     *
     * @since 3.2
     */
    public Tray getParent() {
        checkWidget();
        return parent;
    }

    /**
     * Returns the receiver's tool tip, or null if it has
     * not been set.
     *
     * @return the receiver's tool tip text
     *
     * @exception SWTException <ul>
     *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
     * </ul>
     *
     * @since 3.2
     */
    public ToolTip getToolTip() {
        checkWidget();
        return toolTip;
    }

    /**
     * Returns the receiver's tool tip text, or null if it has
     * not been set.
     *
     * @return the receiver's tool tip text
     *
     * @exception SWTException <ul>
     *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
     * </ul>
     */
    public String getToolTipText() {
        checkWidget();
        return toolTipText;
    }

    /**
     * Returns <code>true</code> if the receiver is visible and
     * <code>false</code> otherwise.
     *
     * @return the receiver's visibility
     *
     * @exception SWTException <ul>
     *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
     * </ul>
     */
    public boolean getVisible() {
        checkWidget();
        return visible;
    }

    long messageProc(long hwnd, int msg, long wParam, long lParam) {
        /*
        * Feature in Windows.  When the user clicks on the tray
        * icon, another application may be the foreground window.
        * This means that the event loop is not running and can
        * cause problems.  For example, if a menu is shown, when
        * the user clicks outside of the menu to cancel it, the
        * menu is not hidden until an event is processed.  If
        * another application is the foreground window, then the
        * menu is not hidden.  The fix is to force the tray icon
        * message window to the foreground when sending an event.
        */
        switch ((int) lParam) {
        case OS.WM_LBUTTONDOWN:
            if (hooks(SWT.Selection)) {
                OS.SetForegroundWindow(hwnd);
                sendSelectionEvent(SWT.Selection);
            }
            break;
        case OS.WM_LBUTTONDBLCLK:
        case OS.WM_RBUTTONDBLCLK:
            if (hooks(SWT.DefaultSelection)) {
                OS.SetForegroundWindow(hwnd);
                sendSelectionEvent(SWT.DefaultSelection);
            }
            break;
        case OS.WM_RBUTTONUP: {
            if (hooks(SWT.MenuDetect)) {
                OS.SetForegroundWindow(hwnd);
                sendEvent(SWT.MenuDetect);
                // widget could be disposed at this point
                if (isDisposed())
                    return 0;
            }
            break;
        }
        case OS.NIN_BALLOONSHOW:
            if (toolTip != null && !toolTip.visible) {
                toolTip.visible = true;
                if (toolTip.hooks(SWT.Show)) {
                    OS.SetForegroundWindow(hwnd);
                    toolTip.sendEvent(SWT.Show);
                    // widget could be disposed at this point
                    if (isDisposed())
                        return 0;
                }
            }
            break;
        case OS.NIN_BALLOONHIDE:
        case OS.NIN_BALLOONTIMEOUT:
        case OS.NIN_BALLOONUSERCLICK:
            if (toolTip != null) {
                if (toolTip.visible) {
                    toolTip.visible = false;
                    if (toolTip.hooks(SWT.Hide)) {
                        OS.SetForegroundWindow(hwnd);
                        toolTip.sendEvent(SWT.Hide);
                        // widget could be disposed at this point
                        if (isDisposed())
                            return 0;
                    }
                }
                if (lParam == OS.NIN_BALLOONUSERCLICK) {
                    if (toolTip.hooks(SWT.Selection)) {
                        OS.SetForegroundWindow(hwnd);
                        toolTip.sendSelectionEvent(SWT.Selection);
                        // widget could be disposed at this point
                        if (isDisposed())
                            return 0;
                    }
                }
            }
            break;
        }
        display.wakeThread();
        return 0;
    }

    void recreate() {
        createUpdateWidget(false);
        if (!visible)
            setVisible(false);
        if (text.length() != 0)
            setText(text);
        if (image != null)
            setImage(image);
        if (toolTipText != null)
            setToolTipText(toolTipText);
    }

    @Override
    void releaseHandle() {
        super.releaseHandle();
        parent = null;
    }

    @Override
    void releaseWidget() {
        super.releaseWidget();
        if (toolTip != null)
            toolTip.item = null;
        toolTip = null;
        if (image2 != null)
            image2.dispose();
        image2 = null;
        highlightImage = null;
        toolTipText = null;
        NOTIFYICONDATA iconData = new NOTIFYICONDATA();
        iconData.cbSize = NOTIFYICONDATA.sizeof;
        iconData.uID = id;
        iconData.hWnd = display.hwndMessage;
        OS.Shell_NotifyIcon(OS.NIM_DELETE, iconData);
    }

    /**
     * Removes the listener from the collection of listeners who will
     * be notified when the receiver is selected by the user.
     *
     * @param listener the listener which should no longer be notified
     *
     * @exception IllegalArgumentException <ul>
     *    <li>ERROR_NULL_ARGUMENT - if the listener is null</li>
     * </ul>
     * @exception SWTException <ul>
     *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
     * </ul>
     *
     * @see SelectionListener
     * @see #addSelectionListener
     */
    public void removeSelectionListener(SelectionListener listener) {
        checkWidget();
        if (listener == null)
            error(SWT.ERROR_NULL_ARGUMENT);
        if (eventTable == null)
            return;
        eventTable.unhook(SWT.Selection, listener);
        eventTable.unhook(SWT.DefaultSelection, listener);
    }

    /**
     * Removes the listener from the collection of listeners who will
     * be notified when the platform-specific context menu trigger has
     * occurred.
     *
     * @param listener the listener which should no longer be notified
     *
     * @exception IllegalArgumentException <ul>
     *    <li>ERROR_NULL_ARGUMENT - if the listener is null</li>
     * </ul>
     * @exception SWTException <ul>
     *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
     * </ul>
     *
     * @see MenuDetectListener
     * @see #addMenuDetectListener
     *
     * @since 3.3
     */
    public void removeMenuDetectListener(MenuDetectListener listener) {
        checkWidget();
        if (listener == null)
            error(SWT.ERROR_NULL_ARGUMENT);
        if (eventTable == null)
            return;
        eventTable.unhook(SWT.MenuDetect, listener);
    }

    /**
     * Sets the receiver's highlight image.
     *
     * @param image the new highlight image
     *
     * @exception IllegalArgumentException <ul>
     *    <li>ERROR_INVALID_ARGUMENT - if the image has been disposed</li>
     * </ul>
     * @exception SWTException <ul>
     *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
     * </ul>
     *
     * @since 3.8
     */
    public void setHighlightImage(Image image) {
        checkWidget();
        if (image != null && image.isDisposed())
            error(SWT.ERROR_INVALID_ARGUMENT);
        highlightImage = image;
    }

    /**
     * Sets the receiver's image.
     *
     * @param image the new image
     *
     * @exception IllegalArgumentException <ul>
     *    <li>ERROR_INVALID_ARGUMENT - if the image has been disposed</li>
     * </ul>
     * @exception SWTException <ul>
     *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
     * </ul>
     */
    @Override
    public void setImage(Image image) {
        checkWidget();
        if (image != null && image.isDisposed())
            error(SWT.ERROR_INVALID_ARGUMENT);
        super.setImage(image);
        if (image2 != null)
            image2.dispose();
        image2 = null;
        long hIcon = 0;
        Image icon = image;
        if (icon != null) {
            switch (icon.type) {
            case SWT.BITMAP:
                image2 = Display.createIcon(image);
                hIcon = image2.handle;
                break;
            case SWT.ICON:
                hIcon = icon.handle;
                break;
            }
        }
        NOTIFYICONDATA iconData = new NOTIFYICONDATA();
        iconData.cbSize = NOTIFYICONDATA.sizeof;
        iconData.uID = id;
        iconData.hWnd = display.hwndMessage;
        iconData.hIcon = hIcon;
        iconData.uFlags = OS.NIF_ICON;
        OS.Shell_NotifyIcon(OS.NIM_MODIFY, iconData);
    }

    /**
     * Sets the receiver's tool tip to the argument, which
     * may be null indicating that no tool tip should be shown.
     *
     * @param toolTip the new tool tip (or null)
     *
     * @exception SWTException <ul>
     *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
     * </ul>
     *
     * @since 3.2
     */
    public void setToolTip(ToolTip toolTip) {
        checkWidget();
        ToolTip oldTip = this.toolTip, newTip = toolTip;
        if (oldTip != null)
            oldTip.item = null;
        this.toolTip = newTip;
        if (newTip != null)
            newTip.item = this;
    }

    /**
     * Sets the receiver's tool tip text to the argument, which
     * may be null indicating that the default tool tip for the
     * control will be shown. For a control that has a default
     * tool tip, such as the Tree control on Windows, setting
     * the tool tip text to an empty string replaces the default,
     * causing no tool tip text to be shown.
     * <p>
     * The mnemonic indicator (character '&amp;') is not displayed in a tool tip.
     * To display a single '&amp;' in the tool tip, the character '&amp;' can be
     * escaped by doubling it in the string.
     * </p>
     * <p>
     * NOTE: This operation is a hint and behavior is platform specific, on Windows
     * for CJK-style mnemonics of the form " (&amp;C)" at the end of the tooltip text
     * are not shown in tooltip.
     * </p>
     *
     * @param string the new tool tip text (or null)
     *
     * @exception SWTException <ul>
     *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
     * </ul>
     */
    public void setToolTipText(String string) {
        checkWidget();
        toolTipText = string;
        NOTIFYICONDATA iconData = new NOTIFYICONDATA();
        if (string != null) {
            char[] szTip = iconData.szTip;
            int length = Math.min(szTip.length - 1, string.length());
            string.getChars(0, length, szTip, 0);
        }
        iconData.cbSize = NOTIFYICONDATA.sizeof;
        iconData.uID = id;
        iconData.hWnd = display.hwndMessage;
        iconData.uFlags = OS.NIF_TIP;
        OS.Shell_NotifyIcon(OS.NIM_MODIFY, iconData);
    }

    /**
     * Makes the receiver visible if the argument is <code>true</code>,
     * and makes it invisible otherwise.
     *
     * @param visible the new visibility state
     *
     * @exception SWTException <ul>
     *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
     *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
     * </ul>
     */
    public void setVisible(boolean visible) {
        checkWidget();
        if (this.visible == visible)
            return;
        if (visible) {
            /*
            * It is possible (but unlikely), that application
            * code could have disposed the widget in the show
            * event.  If this happens, just return.
            */
            sendEvent(SWT.Show);
            if (isDisposed())
                return;
        }
        this.visible = visible;
        NOTIFYICONDATA iconData = new NOTIFYICONDATA();
        iconData.cbSize = NOTIFYICONDATA.sizeof;
        iconData.uID = id;
        iconData.hWnd = display.hwndMessage;
        iconData.uFlags = OS.NIF_STATE;
        iconData.dwState = visible ? 0 : OS.NIS_HIDDEN;
        iconData.dwStateMask = OS.NIS_HIDDEN;
        OS.Shell_NotifyIcon(OS.NIM_MODIFY, iconData);
        if (!visible)
            sendEvent(SWT.Hide);
    }

}