net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/ui/util/SWTUtil.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2004 IBM Corporation and others.
   3  * All rights reserved. This program and the accompanying materials
   4  * are made available under the terms of the Common Public License v1.0
   5  * which accompanies this distribution, and is available at
   6  * http://www.eclipse.org/legal/cpl-v10.html
   7  *
   8  * Contributors:
   9  *     IBM Corporation - initial API and implementation
  10  *******************************************************************************/
  11 package net.sourceforge.phpdt.internal.ui.util;
  12
  13
  14 import org.eclipse.swt.SWT;
  15 import org.eclipse.swt.dnd.DragSource;
  16 import org.eclipse.swt.dnd.DropTarget;
  17 import org.eclipse.swt.layout.GridData;
  18 import org.eclipse.swt.widgets.Button;
  19 import org.eclipse.swt.widgets.Caret;
  20 import org.eclipse.swt.widgets.Control;
  21 import org.eclipse.swt.widgets.Display;
  22 import org.eclipse.swt.widgets.Menu;
  23 import org.eclipse.swt.widgets.ScrollBar;
  24 import org.eclipse.swt.widgets.Shell;
  25 import org.eclipse.swt.widgets.Table;
  26 import org.eclipse.swt.widgets.Widget;
  27
  28 import org.eclipse.jface.dialogs.IDialogConstants;
  29 import org.eclipse.jface.resource.JFaceResources;
  30 import org.eclipse.jface.util.Assert;
  31
  32 /**
  33  * Utility class to simplify access to some SWT resources.
  34  */
  35 public class SWTUtil {
  36
  37         /**
  38          * Returns the standard display to be used. The method first checks, if
  39          * the thread calling this method has an associated disaply. If so, this
  40          * display is returned. Otherwise the method returns the default display.
  41          */
  42         public static Display getStandardDisplay() {
  43                 Display display;
  44                 display= Display.getCurrent();
  45                 if (display == null)
  46                         display= Display.getDefault();
  47                 return display;
  48         }
  49
  50         /**
  51          * Returns the shell for the given widget. If the widget doesn't represent
  52          * a SWT object that manage a shell, <code>null</code> is returned.
  53          *
  54          * @return the shell for the given widget
  55          */
  56         public static Shell getShell(Widget widget) {
  57                 if (widget instanceof Control)
  58                         return ((Control)widget).getShell();
  59                 if (widget instanceof Caret)
  60                         return ((Caret)widget).getParent().getShell();
  61                 if (widget instanceof DragSource)
  62                         return ((DragSource)widget).getControl().getShell();
  63                 if (widget instanceof DropTarget)
  64                         return ((DropTarget)widget).getControl().getShell();
  65                 if (widget instanceof Menu)
  66                         return ((Menu)widget).getParent().getShell();
  67                 if (widget instanceof ScrollBar)
  68                         return ((ScrollBar)widget).getParent().getShell();
  69
  70                 return null;
  71         }
  72
  73
  74         /**
  75          * Returns a width hint for a button control.
  76          */
  77         public static int getButtonWidthHint(Button button) {
  78                 button.setFont(JFaceResources.getDialogFont());
  79                 PixelConverter converter= new PixelConverter(button);
  80                 int widthHint= converter.convertHorizontalDLUsToPixels(IDialogConstants.BUTTON_WIDTH);
  81                 return Math.max(widthHint, button.computeSize(SWT.DEFAULT, SWT.DEFAULT, true).x);
  82         }
  83
  84         /**
  85          * Returns a height hint for a button control.
  86          */
  87         public static int getButtonHeightHint(Button button) {
  88                 button.setFont(JFaceResources.getDialogFont());
  89                 PixelConverter converter= new PixelConverter(button);
  90                 return converter.convertVerticalDLUsToPixels(IDialogConstants.BUTTON_HEIGHT);
  91         }
  92
  93         /**
  94          * Sets width and height hint for the button control.
  95          * <b>Note:</b> This is a NOP if the button's layout data is not
  96          * an instance of <code>GridData</code>.
  97          *
  98          * @param button        the button for which to set the dimension hint
  99          */
 100         public static void setButtonDimensionHint(Button button) {
 101                 Assert.isNotNull(button);
 102                 Object gd= button.getLayoutData();
 103                 if (gd instanceof GridData) {
 104                         ((GridData)gd).heightHint= getButtonHeightHint(button);
 105                         ((GridData)gd).widthHint= getButtonWidthHint(button);
 106                         ((GridData)gd).horizontalAlignment = GridData.FILL;
 107                 }
 108         }
 109
 110         public static int getTableHeightHint(Table table, int rows) {
 111                 if (table.getFont().equals(JFaceResources.getDefaultFont()))
 112                         table.setFont(JFaceResources.getDialogFont());
 113                 int result= table.getItemHeight() * rows + table.getHeaderHeight();
 114                 if (table.getLinesVisible())
 115                         result+= table.getGridLineWidth() * (rows - 1);
 116                 return result;
 117         }
 118
 119
 120 }