| /******************************************************************************* |
| * Copyright (c) 2000, 2008 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.compare.examples.xml; |
| |
| import org.eclipse.core.runtime.Assert; |
| import org.eclipse.jface.dialogs.IDialogConstants; |
| import org.eclipse.swt.SWT; |
| import org.eclipse.swt.dnd.DragSource; |
| import org.eclipse.swt.dnd.DropTarget; |
| import org.eclipse.swt.graphics.GC; |
| import org.eclipse.swt.layout.GridData; |
| import org.eclipse.swt.widgets.Button; |
| import org.eclipse.swt.widgets.Caret; |
| import org.eclipse.swt.widgets.Control; |
| import org.eclipse.swt.widgets.Display; |
| import org.eclipse.swt.widgets.Menu; |
| import org.eclipse.swt.widgets.ScrollBar; |
| import org.eclipse.swt.widgets.Shell; |
| import org.eclipse.swt.widgets.Widget; |
| |
| /** |
| * Utility class to simplify access to some SWT resources. |
| */ |
| public class SWTUtil { |
| |
| /* |
| * Returns the standard display to be used. The method first checks, if |
| * the thread calling this method has an associated disaply. If so, this |
| * display is returned. Otherwise the method returns the default display. |
| */ |
| public static Display getStandardDisplay() { |
| Display display; |
| display= Display.getCurrent(); |
| if (display == null) |
| display= Display.getDefault(); |
| return display; |
| } |
| |
| /* |
| * Returns the shell for the given widget. If the widget doesn't represent |
| * a SWT object that manage a shell, <code>null</code> is returned. |
| * |
| * @return the shell for the given widget |
| */ |
| public static Shell getShell(Widget widget) { |
| if (widget instanceof Control) |
| return ((Control)widget).getShell(); |
| if (widget instanceof Caret) |
| return ((Caret)widget).getParent().getShell(); |
| if (widget instanceof DragSource) |
| return ((DragSource)widget).getControl().getShell(); |
| if (widget instanceof DropTarget) |
| return ((DropTarget)widget).getControl().getShell(); |
| if (widget instanceof Menu) |
| return ((Menu)widget).getParent().getShell(); |
| if (widget instanceof ScrollBar) |
| return ((ScrollBar)widget).getParent().getShell(); |
| return null; |
| } |
| |
| private static double getVerticalDialogUnitSize(Control control) { |
| GC gc= new GC(control); |
| try { |
| int height = gc.getFontMetrics().getHeight(); |
| return height * 0.125; |
| } finally { |
| gc.dispose(); |
| } |
| } |
| |
| private static double getHorizontalDialogUnitSize(Control control) { |
| GC gc= new GC(control); |
| try { |
| int averageWidth= gc.getFontMetrics().getAverageCharWidth(); |
| return averageWidth * 0.25; |
| } finally { |
| gc.dispose(); |
| } |
| } |
| |
| public static int convertHeightInCharsToPixels(int chars, Control control) { |
| return convertVerticalDLUsToPixels(chars * 8, control); |
| } |
| |
| public static int convertHorizontalDLUsToPixels(int dlus, Control control) { |
| return (int)Math.round(dlus * getHorizontalDialogUnitSize(control)); |
| } |
| |
| public static int convertVerticalDLUsToPixels(int dlus, Control control) { |
| return (int)Math.round(dlus * getVerticalDialogUnitSize(control)); |
| } |
| |
| public static int convertWidthInCharsToPixels(int chars, Control control) { |
| return convertHorizontalDLUsToPixels(chars * 4, control); |
| } |
| |
| /* |
| * Returns a width hint for a button control. |
| */ |
| public static int getButtonWidthHint(Button button) { |
| int widthHint= convertHorizontalDLUsToPixels(IDialogConstants.BUTTON_WIDTH, button); |
| return Math.max(widthHint, button.computeSize(SWT.DEFAULT, SWT.DEFAULT, true).x); |
| } |
| |
| /* |
| * Returns a height hint for a button control. |
| */ |
| // public static int getButtonHeigthHint(Button button) { |
| // return convertVerticalDLUsToPixels(IDialogConstants.BUTTON_HEIGHT, button); |
| // } |
| |
| /* |
| * Sets width and height hint for the button control. |
| * <b>Note:</b> This is a NOP if the button's layout data is not |
| * an instance of <code>GridData</code>. |
| * |
| * @param the button for which to set the dimension hint |
| */ |
| public static void setButtonDimensionHint(Button button) { |
| Assert.isNotNull(button); |
| Object gd= button.getLayoutData(); |
| if (gd instanceof GridData) { |
| //((GridData)gd).heightHint= getButtonHeigthHint(button); |
| ((GridData)gd).widthHint= getButtonWidthHint(button); |
| } |
| } |
| } |