Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2015 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 * Jan-Ove Weichel <janove.weichel@vogella.com> - Bug 475879 *******************************************************************************/ package org.eclipse.jface.action; import org.eclipse.core.commands.ExecutionException; import org.eclipse.core.commands.NotEnabledException; import org.eclipse.jface.action.ExternalActionManager.IBindingManagerCallback; import org.eclipse.jface.bindings.Trigger; import org.eclipse.jface.bindings.TriggerSequence; import org.eclipse.jface.bindings.keys.IKeyLookup; import org.eclipse.jface.bindings.keys.KeyLookupFactory; import org.eclipse.jface.bindings.keys.KeyStroke; import org.eclipse.jface.resource.ImageDescriptor; import org.eclipse.jface.resource.JFaceResources; import org.eclipse.jface.resource.LocalResourceManager; import org.eclipse.jface.resource.ResourceManager; import org.eclipse.jface.util.IPropertyChangeListener; import org.eclipse.jface.util.Policy; import org.eclipse.jface.util.PropertyChangeEvent; import org.eclipse.jface.util.Util; import org.eclipse.swt.SWT; import org.eclipse.swt.graphics.GC; import org.eclipse.swt.graphics.Point; import org.eclipse.swt.widgets.Button; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Event; import org.eclipse.swt.widgets.Item; import org.eclipse.swt.widgets.Listener; import org.eclipse.swt.widgets.Menu; import org.eclipse.swt.widgets.MenuItem; import org.eclipse.swt.widgets.ToolBar; import org.eclipse.swt.widgets.ToolItem; import org.eclipse.swt.widgets.Widget; /** * A contribution item which delegates to an action. * <p> * This class may be instantiated; it is not intended to be subclassed. * </p> * @noextend This class is not intended to be subclassed by clients. */ public class ActionContributionItem extends ContributionItem { /** * Mode bit: Show text on tool items or buttons, even if an image is * present. If this mode bit is not set, text is only shown on tool items if * there is no image present. * * @since 3.0 */ public static int MODE_FORCE_TEXT = 1; /** a string inserted in the middle of text that has been shortened */ private static final String ellipsis = "..."; //$NON-NLS-1$ /** * Stores the result of the action. False when the action returned failure. */ private Boolean result = null; private static boolean USE_COLOR_ICONS = true; /** * Returns whether color icons should be used in toolbars. * * @return <code>true</code> if color icons should be used in toolbars, * <code>false</code> otherwise */ public static boolean getUseColorIconsInToolbars() { return USE_COLOR_ICONS; } /** * Sets whether color icons should be used in toolbars. * * @param useColorIcons * <code>true</code> if color icons should be used in toolbars, * <code>false</code> otherwise */ public static void setUseColorIconsInToolbars(boolean useColorIcons) { USE_COLOR_ICONS = useColorIcons; } /** * The presentation mode. */ private int mode = 0; /** * The action. */ private IAction action; /** * The listener for changes to the text of the action contributed by an * external source. */ private final IPropertyChangeListener actionTextListener = event -> update(event.getProperty()); /** * Remembers all images in use by this contribution item */ private LocalResourceManager imageManager; /** * Listener for SWT button widget events. */ private Listener buttonListener; /** * Listener for SWT menu item widget events. */ private Listener menuItemListener; /** * Listener for action property change notifications. */ private final IPropertyChangeListener propertyListener = event -> actionPropertyChange(event); /** * Listener for SWT tool item widget events. */ private Listener toolItemListener; /** * The widget created for this item; <code>null</code> before creation and * after disposal. */ private Widget widget = null; private Listener menuCreatorListener; /** * Creates a new contribution item from the given action. The id of the * action is used as the id of the item. * * @param action * the action */ public ActionContributionItem(IAction action) { super(action.getId()); this.action = action; } /** * Handles a property change event on the action (forwarded by nested * listener). */ private void actionPropertyChange(final PropertyChangeEvent e) { // This code should be removed. Avoid using free asyncExec if (isVisible() && widget != null) { Display display = widget.getDisplay(); if (display.getThread() == Thread.currentThread()) { update(e.getProperty()); } else { display.asyncExec(() -> update(e.getProperty())); } } } /** * Compares this action contribution item with another object. Two action * contribution items are equal if they refer to the identical Action. */ @Override public boolean equals(Object o) { if (!(o instanceof ActionContributionItem)) { return false; } return action.equals(((ActionContributionItem) o).action); } /** * The <code>ActionContributionItem</code> implementation of this * <code>IContributionItem</code> method creates an SWT * <code>Button</code> for the action using the action's style. If the * action's checked property has been set, the button is created and primed * to the value of the checked property. */ @Override public void fill(Composite parent) { if (widget == null && parent != null) { int flags = SWT.PUSH; if (action != null) { if (action.getStyle() == IAction.AS_CHECK_BOX) { flags = SWT.TOGGLE; } if (action.getStyle() == IAction.AS_RADIO_BUTTON) { flags = SWT.RADIO; } } Button b = new Button(parent, flags); b.setData(this); b.addListener(SWT.Dispose, getButtonListener()); // Don't hook a dispose listener on the parent b.addListener(SWT.Selection, getButtonListener()); if (action.getHelpListener() != null) { b.addHelpListener(action.getHelpListener()); } widget = b; update(null); // Attach some extra listeners. action.addPropertyChangeListener(propertyListener); if (action != null) { String commandId = action.getActionDefinitionId(); ExternalActionManager.ICallback callback = ExternalActionManager.getInstance().getCallback(); if ((callback != null) && (commandId != null)) { callback.addPropertyChangeListener(commandId, actionTextListener); } } } } /** * The <code>ActionContributionItem</code> implementation of this * <code>IContributionItem</code> method creates an SWT * <code>MenuItem</code> for the action using the action's style. If the * action's checked property has been set, a button is created and primed to * the value of the checked property. If the action's menu creator property * has been set, a cascading submenu is created. */ @Override public void fill(Menu parent, int index) { if (widget == null && parent != null) { int flags = SWT.PUSH; if (action != null) { int style = action.getStyle(); if (style == IAction.AS_CHECK_BOX) { flags = SWT.CHECK; } else if (style == IAction.AS_RADIO_BUTTON) { flags = SWT.RADIO; } else if (style == IAction.AS_DROP_DOWN_MENU) { flags = SWT.CASCADE; } } MenuItem mi = null; if (index >= 0) { mi = new MenuItem(parent, flags, index); } else { mi = new MenuItem(parent, flags); } widget = mi; mi.setData(this); mi.addListener(SWT.Dispose, getMenuItemListener()); mi.addListener(SWT.Selection, getMenuItemListener()); if (action.getHelpListener() != null) { mi.addHelpListener(action.getHelpListener()); } if (flags == SWT.CASCADE) { // just create a proxy for now, if the user shows it then // fill it in Menu subMenu = new Menu(parent); subMenu.addListener(SWT.Show, getMenuCreatorListener()); subMenu.addListener(SWT.Hide, getMenuCreatorListener()); mi.setMenu(subMenu); } update(null); // Attach some extra listeners. action.addPropertyChangeListener(propertyListener); if (action != null) { String commandId = action.getActionDefinitionId(); ExternalActionManager.ICallback callback = ExternalActionManager.getInstance().getCallback(); if ((callback != null) && (commandId != null)) { callback.addPropertyChangeListener(commandId, actionTextListener); } } } } /** * The <code>ActionContributionItem</code> implementation of this , * <code>IContributionItem</code> method creates an SWT * <code>ToolItem</code> for the action using the action's style. If the * action's checked property has been set, a button is created and primed to * the value of the checked property. If the action's menu creator property * has been set, a drop-down tool item is created. */ @Override public void fill(ToolBar parent, int index) { if (widget == null && parent != null) { int flags = SWT.PUSH; if (action != null) { int style = action.getStyle(); if (style == IAction.AS_CHECK_BOX) { flags = SWT.CHECK; } else if (style == IAction.AS_RADIO_BUTTON) { flags = SWT.RADIO; } else if (style == IAction.AS_DROP_DOWN_MENU) { flags = SWT.DROP_DOWN; } } ToolItem ti = null; if (index >= 0) { ti = new ToolItem(parent, flags, index); } else { ti = new ToolItem(parent, flags); } ti.setData(this); ti.addListener(SWT.Selection, getToolItemListener()); ti.addListener(SWT.Dispose, getToolItemListener()); widget = ti; update(null); // Attach some extra listeners. action.addPropertyChangeListener(propertyListener); if (action != null) { String commandId = action.getActionDefinitionId(); ExternalActionManager.ICallback callback = ExternalActionManager.getInstance().getCallback(); if ((callback != null) && (commandId != null)) { callback.addPropertyChangeListener(commandId, actionTextListener); } } } } /** * Returns the action associated with this contribution item. * * @return the action */ public IAction getAction() { return action; } /** * Returns the listener for SWT button widget events. * * @return a listener for button events */ private Listener getButtonListener() { if (buttonListener == null) { buttonListener = event -> { switch (event.type) { case SWT.Dispose: handleWidgetDispose(event); break; case SWT.Selection: Widget ew = event.widget; if (ew != null) { handleWidgetSelection(event, ((Button) ew).getSelection()); } break; } }; } return buttonListener; } /** * Returns the listener for SWT menu item widget events. * * @return a listener for menu item events */ private Listener getMenuItemListener() { if (menuItemListener == null) { menuItemListener = event -> { switch (event.type) { case SWT.Dispose: handleWidgetDispose(event); break; case SWT.Selection: Widget ew = event.widget; if (ew != null) { handleWidgetSelection(event, ((MenuItem) ew).getSelection()); } break; } }; } return menuItemListener; } /** * Returns the presentation mode, which is the bitwise-or of the * <code>MODE_*</code> constants. The default mode setting is 0, meaning * that for menu items, both text and image are shown (if present), but for * tool items, the text is shown only if there is no image. * * @return the presentation mode settings * * @since 3.0 */ public int getMode() { return mode; } /** * Returns the listener for SWT tool item widget events. * * @return a listener for tool item events */ private Listener getToolItemListener() { if (toolItemListener == null) { toolItemListener = event -> { switch (event.type) { case SWT.Dispose: handleWidgetDispose(event); break; case SWT.Selection: Widget ew = event.widget; if (ew != null) { handleWidgetSelection(event, ((ToolItem) ew).getSelection()); } break; } }; } return toolItemListener; } /** * Handles a widget dispose event for the widget corresponding to this item. */ private void handleWidgetDispose(Event e) { // Check if our widget is the one being disposed. if (e.widget == widget) { // Dispose of the menu creator. if (action.getStyle() == IAction.AS_DROP_DOWN_MENU && menuCreatorCalled) { IMenuCreator mc = action.getMenuCreator(); if (mc != null) { mc.dispose(); } } // Unhook all of the listeners. action.removePropertyChangeListener(propertyListener); if (action != null) { String commandId = action.getActionDefinitionId(); ExternalActionManager.ICallback callback = ExternalActionManager.getInstance().getCallback(); if ((callback != null) && (commandId != null)) { callback.removePropertyChangeListener(commandId, actionTextListener); } } // Clear the widget field. widget = null; disposeOldImages(); } } /** * Handles a widget selection event. */ private void handleWidgetSelection(Event e, boolean selection) { Widget item = e.widget; if (item != null) { int style = item.getStyle(); if ((style & (SWT.TOGGLE | SWT.CHECK)) != 0) { if (action.getStyle() == IAction.AS_CHECK_BOX) { action.setChecked(selection); } } else if ((style & SWT.RADIO) != 0) { if (action.getStyle() == IAction.AS_RADIO_BUTTON) { action.setChecked(selection); } } else if ((style & SWT.DROP_DOWN) != 0) { if (e.detail == 4) { // on drop-down button if (action.getStyle() == IAction.AS_DROP_DOWN_MENU) { IMenuCreator mc = action.getMenuCreator(); menuCreatorCalled = true; ToolItem ti = (ToolItem) item; // we create the menu as a sub-menu of "dummy" so that // we can use // it in a cascading menu too. // If created on a SWT control we would get an SWT // error... // Menu dummy= new Menu(ti.getParent()); // Menu m= mc.getMenu(dummy); // dummy.dispose(); if (mc != null) { Menu m = mc.getMenu(ti.getParent()); if (m != null) { // position the menu below the drop down item Point point = ti.getParent().toDisplay(new Point(e.x, e.y)); m.setLocation(point.x, point.y); // waiting // for SWT // 0.42 m.setVisible(true); return; // we don't fire the action } } } } } ExternalActionManager.IExecuteCallback callback = null; String actionDefinitionId = action.getActionDefinitionId(); if (actionDefinitionId != null) { Object obj = ExternalActionManager.getInstance().getCallback(); if (obj instanceof ExternalActionManager.IExecuteCallback) { callback = (ExternalActionManager.IExecuteCallback) obj; } } // Ensure action is enabled first. // See 1GAN3M6: ITPUI:WINNT - Any IAction in the workbench can be // executed while disabled. if (action.isEnabled()) { boolean trace = Policy.TRACE_ACTIONS; long ms = 0L; if (trace) { ms = System.currentTimeMillis(); System.out.println("Running action: " + action.getText()); //$NON-NLS-1$ } IPropertyChangeListener resultListener = null; if (callback != null) { resultListener = event -> { // Check on result if (event.getProperty().equals(IAction.RESULT)) { if (event.getNewValue() instanceof Boolean) { result = (Boolean) event.getNewValue(); } } }; action.addPropertyChangeListener(resultListener); callback.preExecute(action, e); } action.runWithEvent(e); if (callback != null) { if (result == null || result.equals(Boolean.TRUE)) { callback.postExecuteSuccess(action, Boolean.TRUE); } else { callback.postExecuteFailure(action, new ExecutionException(action.getText() + " returned failure.")); //$NON-NLS-1$ } } if (resultListener != null) { result = null; action.removePropertyChangeListener(resultListener); } if (trace) { System.out .println((System.currentTimeMillis() - ms) + " ms to run action: " + action.getText()); //$NON-NLS-1$ } } else { if (callback != null) { callback.notEnabled(action, new NotEnabledException(action.getText() + " is not enabled.")); //$NON-NLS-1$ } } } } @Override public int hashCode() { return action.hashCode(); } /** * Returns whether the given action has any images. * * @param actionToCheck * the action * @return <code>true</code> if the action has any images, * <code>false</code> if not */ private boolean hasImages(IAction actionToCheck) { return actionToCheck.getImageDescriptor() != null || actionToCheck.getHoverImageDescriptor() != null || actionToCheck.getDisabledImageDescriptor() != null; } /** * Returns whether the command corresponding to this action is active. */ private boolean isCommandActive() { IAction actionToCheck = getAction(); if (actionToCheck != null) { String commandId = actionToCheck.getActionDefinitionId(); ExternalActionManager.ICallback callback = ExternalActionManager.getInstance().getCallback(); if (callback != null) { return callback.isActive(commandId); } } return true; } /** * The action item implementation of this <code>IContributionItem</code> * method returns <code>true</code> for menu items and <code>false</code> * for everything else. */ @Override public boolean isDynamic() { if (widget instanceof MenuItem) { // Optimization. Only recreate the item is the check or radio style // has changed. boolean itemIsCheck = (widget.getStyle() & SWT.CHECK) != 0; boolean actionIsCheck = getAction() != null && getAction().getStyle() == IAction.AS_CHECK_BOX; boolean itemIsRadio = (widget.getStyle() & SWT.RADIO) != 0; boolean actionIsRadio = getAction() != null && getAction().getStyle() == IAction.AS_RADIO_BUTTON; return (itemIsCheck != actionIsCheck) || (itemIsRadio != actionIsRadio); } return false; } @Override public boolean isEnabled() { return action != null && action.isEnabled(); } /** * Returns <code>true</code> if this item is allowed to enable, * <code>false</code> otherwise. * * @return if this item is allowed to be enabled * @since 2.0 */ protected boolean isEnabledAllowed() { if (getParent() == null) { return true; } Boolean value = getParent().getOverrides().getEnabled(this); return (value == null) ? true : value.booleanValue(); } /** * The <code>ActionContributionItem</code> implementation of this * <code>ContributionItem</code> method extends the super implementation * by also checking whether the command corresponding to this action is * active. */ @Override public boolean isVisible() { return super.isVisible() && isCommandActive(); } /** * Sets the presentation mode, which is the bitwise-or of the * <code>MODE_*</code> constants. * * @param mode * the presentation mode settings * * @since 3.0 */ public void setMode(int mode) { this.mode = mode; update(); } /** * The action item implementation of this <code>IContributionItem</code> * method calls <code>update(null)</code>. */ @Override public final void update() { update(null); } /** * Synchronizes the UI with the given property. * * @param propertyName * the name of the property, or <code>null</code> meaning all * applicable properties */ @Override public void update(String propertyName) { if (widget != null) { // determine what to do boolean textChanged = propertyName == null || propertyName.equals(IAction.TEXT); boolean imageChanged = propertyName == null || propertyName.equals(IAction.IMAGE); boolean tooltipTextChanged = propertyName == null || propertyName.equals(IAction.TOOL_TIP_TEXT); boolean enableStateChanged = propertyName == null || propertyName.equals(IAction.ENABLED) || propertyName.equals(IContributionManagerOverrides.P_ENABLED); boolean checkChanged = (action.getStyle() == IAction.AS_CHECK_BOX || action.getStyle() == IAction.AS_RADIO_BUTTON) && (propertyName == null || propertyName.equals(IAction.CHECKED)); if (widget instanceof ToolItem) { ToolItem ti = (ToolItem) widget; String text = action.getText(); // the set text is shown only if there is no image or if forced // by MODE_FORCE_TEXT boolean showText = text != null && ((getMode() & MODE_FORCE_TEXT) != 0 || !hasImages(action)); // only do the trimming if the text will be used if (showText && text != null) { text = Action.removeAcceleratorText(text); text = Action.removeMnemonics(text); } if (textChanged) { String textToSet = showText ? text : ""; //$NON-NLS-1$ boolean rightStyle = (ti.getParent().getStyle() & SWT.RIGHT) != 0; if (rightStyle || !ti.getText().equals(textToSet)) { // In addition to being required to update the text if // it // gets nulled out in the action, this is also a // workaround // for bug 50151: Using SWT.RIGHT on a ToolBar leaves // blank space ti.setText(textToSet); } } if (imageChanged) { // only substitute a missing image if it has no text updateImages(!showText); } if (tooltipTextChanged || textChanged) { String toolTip = action.getToolTipText(); if ((toolTip == null) || (toolTip.length() == 0)) { toolTip = text; } ExternalActionManager.ICallback callback = ExternalActionManager.getInstance().getCallback(); String commandId = action.getActionDefinitionId(); if ((callback != null) && (commandId != null) && (toolTip != null)) { String acceleratorText = callback.getAcceleratorText(commandId); if (acceleratorText != null && acceleratorText.length() != 0) { toolTip = JFaceResources.format("Toolbar_Tooltip_Accelerator", //$NON-NLS-1$ toolTip, acceleratorText); } } // if the text is showing, then only set the tooltip if // different if (!showText || toolTip != null && !toolTip.equals(text)) { ti.setToolTipText(toolTip); } else { ti.setToolTipText(null); } } if (enableStateChanged) { boolean shouldBeEnabled = action.isEnabled() && isEnabledAllowed(); if (ti.getEnabled() != shouldBeEnabled) { ti.setEnabled(shouldBeEnabled); } } if (checkChanged) { boolean bv = action.isChecked(); if (ti.getSelection() != bv) { ti.setSelection(bv); } } return; } if (widget instanceof MenuItem) { MenuItem mi = (MenuItem) widget; if (textChanged) { int accelerator = 0; String acceleratorText = null; IAction updatedAction = getAction(); String text = null; accelerator = updatedAction.getAccelerator(); ExternalActionManager.ICallback callback = ExternalActionManager.getInstance().getCallback(); // Block accelerators that are already in use. if ((accelerator != 0) && (callback != null) && (callback.isAcceleratorInUse(accelerator))) { accelerator = 0; } /* * Process accelerators on GTK in a special way to avoid Bug * 42009. We will override the native input method by * allowing these reserved accelerators to be placed on the * menu. We will only do this for "Ctrl+Shift+[0-9A-FU]". */ final String commandId = updatedAction.getActionDefinitionId(); if ((Util.isGtk()) && (callback instanceof IBindingManagerCallback) && (commandId != null)) { final IBindingManagerCallback bindingManagerCallback = (IBindingManagerCallback) callback; final IKeyLookup lookup = KeyLookupFactory.getDefault(); final TriggerSequence[] triggerSequences = bindingManagerCallback .getActiveBindingsFor(commandId); for (int i = 0; i < triggerSequences.length; i++) { final TriggerSequence triggerSequence = triggerSequences[i]; final Trigger[] triggers = triggerSequence.getTriggers(); if (triggers.length == 1) { final Trigger trigger = triggers[0]; if (trigger instanceof KeyStroke) { final KeyStroke currentKeyStroke = (KeyStroke) trigger; final int currentNaturalKey = currentKeyStroke.getNaturalKey(); if ((currentKeyStroke .getModifierKeys() == (lookup.getCtrl() | lookup.getShift())) && ((currentNaturalKey >= '0' && currentNaturalKey <= '9') || (currentNaturalKey >= 'A' && currentNaturalKey <= 'F') || (currentNaturalKey == 'U'))) { accelerator = currentKeyStroke.getModifierKeys() | currentNaturalKey; acceleratorText = triggerSequence.format(); break; } } } } } if (accelerator == 0) { if ((callback != null) && (commandId != null)) { acceleratorText = callback.getAcceleratorText(commandId); } } IContributionManagerOverrides overrides = null; if (getParent() != null) { overrides = getParent().getOverrides(); } if (overrides != null) { text = getParent().getOverrides().getText(this); } mi.setAccelerator(accelerator); if (text == null) { text = updatedAction.getText(); } if (text != null && acceleratorText == null) { // use extracted accelerator text in case accelerator // cannot be fully represented in one int (e.g. // multi-stroke keys) acceleratorText = LegacyActionTools.extractAcceleratorText(text); if (acceleratorText == null && accelerator != 0) { acceleratorText = Action.convertAccelerator(accelerator); } } if (text == null) { text = ""; //$NON-NLS-1$ } else { text = Action.removeAcceleratorText(text); } if (acceleratorText == null) { mi.setText(text); } else { mi.setText(text + '\t' + acceleratorText); } } if (imageChanged) { updateImages(false); } if (enableStateChanged) { boolean shouldBeEnabled = action.isEnabled() && isEnabledAllowed(); if (mi.getEnabled() != shouldBeEnabled) { mi.setEnabled(shouldBeEnabled); } } if (checkChanged) { boolean bv = action.isChecked(); if (mi.getSelection() != bv) { mi.setSelection(bv); } } return; } if (widget instanceof Button) { Button button = (Button) widget; if (imageChanged) { updateImages(false); } if (textChanged) { String text = action.getText(); boolean showText = text != null && ((getMode() & MODE_FORCE_TEXT) != 0 || !hasImages(action)); // only do the trimming if the text will be used if (showText) { text = Action.removeAcceleratorText(text); } String textToSet = showText ? text : ""; //$NON-NLS-1$ button.setText(textToSet); } if (tooltipTextChanged) { button.setToolTipText(action.getToolTipText()); } if (enableStateChanged) { boolean shouldBeEnabled = action.isEnabled() && isEnabledAllowed(); if (button.getEnabled() != shouldBeEnabled) { button.setEnabled(shouldBeEnabled); } } if (checkChanged) { boolean bv = action.isChecked(); if (button.getSelection() != bv) { button.setSelection(bv); } } return; } } } /** * Updates the images for this action. * * @param forceImage * <code>true</code> if some form of image is compulsory, and * <code>false</code> if it is acceptable for this item to have * no image * @return <code>true</code> if there are images for this action, * <code>false</code> if not */ private boolean updateImages(boolean forceImage) { ResourceManager parentResourceManager = JFaceResources.getResources(); if (widget instanceof ToolItem) { if (USE_COLOR_ICONS) { ImageDescriptor image = action.getHoverImageDescriptor(); if (image == null) { image = action.getImageDescriptor(); } ImageDescriptor disabledImage = action.getDisabledImageDescriptor(); // Make sure there is a valid image. if (image == null && forceImage) { image = ImageDescriptor.getMissingImageDescriptor(); } LocalResourceManager localManager = new LocalResourceManager(parentResourceManager); // performance: more efficient in SWT to set disabled and hot // image before regular image ((ToolItem) widget).setDisabledImage( disabledImage == null ? null : localManager.createImageWithDefault(disabledImage)); ((ToolItem) widget).setImage(image == null ? null : localManager.createImageWithDefault(image)); disposeOldImages(); imageManager = localManager; return image != null; } ImageDescriptor image = action.getImageDescriptor(); ImageDescriptor hoverImage = action.getHoverImageDescriptor(); ImageDescriptor disabledImage = action.getDisabledImageDescriptor(); // If there is no regular image, but there is a hover image, // convert the hover image to gray and use it as the regular image. if (image == null && hoverImage != null) { image = ImageDescriptor.createWithFlags(action.getHoverImageDescriptor(), SWT.IMAGE_GRAY); } else { // If there is no hover image, use the regular image as the // hover image, // and convert the regular image to gray if (hoverImage == null && image != null) { hoverImage = image; image = ImageDescriptor.createWithFlags(action.getImageDescriptor(), SWT.IMAGE_GRAY); } } // Make sure there is a valid image. if (hoverImage == null && image == null && forceImage) { image = ImageDescriptor.getMissingImageDescriptor(); } // Create a local resource manager to remember the images we've // allocated for this tool item LocalResourceManager localManager = new LocalResourceManager(parentResourceManager); // performance: more efficient in SWT to set disabled and hot image // before regular image ((ToolItem) widget).setDisabledImage( disabledImage == null ? null : localManager.createImageWithDefault(disabledImage)); ((ToolItem) widget) .setHotImage(hoverImage == null ? null : localManager.createImageWithDefault(hoverImage)); ((ToolItem) widget).setImage(image == null ? null : localManager.createImageWithDefault(image)); // Now that we're no longer referencing the old images, clear them // out. disposeOldImages(); imageManager = localManager; return image != null; } else if (widget instanceof Item || widget instanceof Button) { // Use hover image if there is one, otherwise use regular image. ImageDescriptor image = action.getHoverImageDescriptor(); if (image == null) { image = action.getImageDescriptor(); } // Make sure there is a valid image. if (image == null && forceImage) { image = ImageDescriptor.getMissingImageDescriptor(); } // Create a local resource manager to remember the images we've // allocated for this widget LocalResourceManager localManager = new LocalResourceManager(parentResourceManager); if (widget instanceof Item) { ((Item) widget).setImage(image == null ? null : localManager.createImageWithDefault(image)); } else if (widget instanceof Button) { ((Button) widget).setImage(image == null ? null : localManager.createImageWithDefault(image)); } // Now that we're no longer referencing the old images, clear them // out. disposeOldImages(); imageManager = localManager; return image != null; } return false; } /** * Dispose any images allocated for this contribution item */ private void disposeOldImages() { if (imageManager != null) { imageManager.dispose(); imageManager = null; } } /** * Shorten the given text <code>t</code> so that its length doesn't exceed * the width of the given ToolItem.The default implementation replaces * characters in the center of the original string with an ellipsis ("..."). * Override if you need a different strategy. * * @param textValue * the text to shorten * @param item * the tool item the text belongs to * @return the shortened string * */ protected String shortenText(String textValue, ToolItem item) { if (textValue == null) { return null; } GC gc = new GC(item.getParent()); int maxWidth = item.getImage().getBounds().width * 4; if (gc.textExtent(textValue).x < maxWidth) { gc.dispose(); return textValue; } for (int i = textValue.length(); i > 0; i--) { String test = textValue.substring(0, i); test = test + ellipsis; if (gc.textExtent(test).x < maxWidth) { gc.dispose(); return test; } } gc.dispose(); // If for some reason we fall through abort return textValue; } @Override public void dispose() { if (widget != null) { widget.dispose(); widget = null; } holdMenu = null; } /** * Handle show and hide on the proxy menu for IAction.AS_DROP_DOWN_MENU * actions. * * @return the appropriate listener * @since 3.4 */ private Listener getMenuCreatorListener() { if (menuCreatorListener == null) { menuCreatorListener = event -> { switch (event.type) { case SWT.Show: handleShowProxy((Menu) event.widget); break; case SWT.Hide: handleHideProxy((Menu) event.widget); break; } }; } return menuCreatorListener; } /** * This is the easiest way to hold the menu until we can swap it in to the * proxy. */ private Menu holdMenu = null; private boolean menuCreatorCalled = false; /** * The proxy menu is being shown, we better get the real menu. * * @param proxy * the proxy menu * @since 3.4 */ private void handleShowProxy(Menu proxy) { proxy.removeListener(SWT.Show, getMenuCreatorListener()); IMenuCreator mc = action.getMenuCreator(); menuCreatorCalled = true; if (mc == null) { return; } holdMenu = mc.getMenu(proxy.getParentMenu()); if (holdMenu == null) { return; } copyMenu(holdMenu, proxy); } /** * Create MenuItems in the proxy menu that can execute the real menu items * if selected. Create proxy menus for any real item submenus. * * @param realMenu * the real menu to copy from * @param proxy * the proxy menu to populate * @since 3.4 */ private void copyMenu(Menu realMenu, Menu proxy) { if (realMenu.isDisposed() || proxy.isDisposed()) { return; } // we notify the real menu so it can populate itself if it was // listening for SWT.Show realMenu.notifyListeners(SWT.Show, null); final Listener passThrough = event -> { if (!event.widget.isDisposed()) { Widget realItem = (Widget) event.widget.getData(); if (!realItem.isDisposed()) { int style = event.widget.getStyle(); if (event.type == SWT.Selection && ((style & (SWT.TOGGLE | SWT.CHECK | SWT.RADIO)) != 0) && realItem instanceof MenuItem) { ((MenuItem) realItem).setSelection(((MenuItem) event.widget).getSelection()); } event.widget = realItem; realItem.notifyListeners(event.type, event); } } }; MenuItem[] items = realMenu.getItems(); for (int i = 0; i < items.length; i++) { final MenuItem realItem = items[i]; final MenuItem proxyItem = new MenuItem(proxy, realItem.getStyle()); proxyItem.setData(realItem); proxyItem.setAccelerator(realItem.getAccelerator()); proxyItem.setEnabled(realItem.getEnabled()); proxyItem.setImage(realItem.getImage()); proxyItem.setSelection(realItem.getSelection()); proxyItem.setText(realItem.getText()); // pass through any events proxyItem.addListener(SWT.Selection, passThrough); proxyItem.addListener(SWT.Arm, passThrough); proxyItem.addListener(SWT.Help, passThrough); final Menu itemMenu = realItem.getMenu(); if (itemMenu != null) { // create a proxy for any sub menu items final Menu subMenu = new Menu(proxy); subMenu.setData(itemMenu); proxyItem.setMenu(subMenu); subMenu.addListener(SWT.Show, new Listener() { @Override public void handleEvent(Event event) { event.widget.removeListener(SWT.Show, this); if (event.type == SWT.Show) { copyMenu(itemMenu, subMenu); } } }); subMenu.addListener(SWT.Help, passThrough); subMenu.addListener(SWT.Hide, passThrough); } } } /** * The proxy menu is being hidden, so we need to make it go away. * * @param proxy * the proxy menu * @since 3.4 */ private void handleHideProxy(final Menu proxy) { proxy.removeListener(SWT.Hide, getMenuCreatorListener()); proxy.getDisplay().asyncExec(() -> { if (!proxy.isDisposed()) { MenuItem parentItem = proxy.getParentItem(); proxy.dispose(); parentItem.setMenu(holdMenu); } if (holdMenu != null && !holdMenu.isDisposed()) { holdMenu.notifyListeners(SWT.Hide, null); } holdMenu = null; }); } /** * Return the widget associated with this contribution item. It should not * be cached, as it can be disposed and re-created by its containing * ContributionManager, which controls all of the widgets lifecycle methods. * <p> * This can be used to set layout data on the widget if appropriate. The * actual type of the widget can be any valid control for this * ContributionItem's current ContributionManager. * </p> * * @return the widget, or <code>null</code> depending on the lifecycle. * @since 3.4 */ public Widget getWidget() { return widget; } }