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

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2003 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 import java.util.ArrayList;
  14 import java.util.List;
  15
  16 import org.eclipse.jface.util.Assert;
  17 import org.eclipse.jface.viewers.ColumnLayoutData;
  18 import org.eclipse.jface.viewers.ColumnPixelData;
  19 import org.eclipse.jface.viewers.ColumnWeightData;
  20 import org.eclipse.swt.SWT;
  21 import org.eclipse.swt.events.ControlAdapter;
  22 import org.eclipse.swt.events.ControlEvent;
  23 import org.eclipse.swt.graphics.Point;
  24 import org.eclipse.swt.graphics.Rectangle;
  25 import org.eclipse.swt.widgets.Composite;
  26 import org.eclipse.swt.widgets.Table;
  27 import org.eclipse.swt.widgets.TableColumn;
  28
  29 /**
  30  * A special composite to layout columns inside a table. The composite is needed since we have
  31  * to layout the columns "before" the actual table gets layouted. Hence we can't use a normal
  32  * layout manager.
  33  */
  34 public class TableLayoutComposite extends Composite {
  35
  36         private List columns= new ArrayList();
  37
  38         /**
  39          * Creates a new <code>TableLayoutComposite</code>.
  40          */
  41         public TableLayoutComposite(Composite parent, int style) {
  42                 super(parent, style);
  43         addControlListener(new ControlAdapter() {
  44             public void controlResized(ControlEvent e) {
  45                 Rectangle area= getClientArea();
  46                 Table table= (Table)getChildren()[0];
  47                 Point preferredSize= computeTableSize(table);
  48                 int width= area.width - 2 * table.getBorderWidth();
  49                 if (preferredSize.y > area.height) {
  50                     // Subtract the scrollbar width from the total column width
  51                     // if a vertical scrollbar will be required
  52                     Point vBarSize = table.getVerticalBar().getSize();
  53                     width -= vBarSize.x;
  54                 }
  55                 layoutTable(table, width, area, table.getSize().x < area.width);
  56             }
  57         });
  58         }
  59
  60         /**
  61          * Adds a new column of data to this table layout.
  62          *
  63          * @param data the column layout data
  64          */
  65         public void addColumnData(ColumnLayoutData data) {
  66                 columns.add(data);
  67         }
  68
  69         //---- Helpers -------------------------------------------------------------------------------------
  70
  71         private Point computeTableSize(Table table) {
  72                 Point result= table.computeSize(SWT.DEFAULT, SWT.DEFAULT);
  73
  74                 int width= 0;
  75                 int size= columns.size();
  76                 for (int i= 0; i < size; ++i) {
  77                         ColumnLayoutData layoutData= (ColumnLayoutData) columns.get(i);
  78                         if (layoutData instanceof ColumnPixelData) {
  79                                 ColumnPixelData col= (ColumnPixelData) layoutData;
  80                                 width += col.width;
  81                         } else if (layoutData instanceof ColumnWeightData) {
  82                                 ColumnWeightData col= (ColumnWeightData) layoutData;
  83                                 width += col.minimumWidth;
  84                         } else {
  85                                 Assert.isTrue(false, "Unknown column layout data"); //$NON-NLS-1$
  86                         }
  87                 }
  88                 if (width > result.x)
  89                         result.x= width;
  90                 return result;
  91         }
  92
  93         private void layoutTable(Table table, int width, Rectangle area, boolean increase) {
  94                 // XXX: Layout is being called with an invalid value the first time
  95                 // it is being called on Linux. This method resets the
  96                 // Layout to null so we make sure we run it only when
  97                 // the value is OK.
  98                 if (width <= 1)
  99                         return;
 100
 101                 TableColumn[] tableColumns= table.getColumns();
 102                 int size= Math.min(columns.size(), tableColumns.length);
 103                 int[] widths= new int[size];
 104                 int fixedWidth= 0;
 105                 int numberOfWeightColumns= 0;
 106                 int totalWeight= 0;
 107
 108                 // First calc space occupied by fixed columns
 109                 for (int i= 0; i < size; i++) {
 110                         ColumnLayoutData col= (ColumnLayoutData) columns.get(i);
 111                         if (col instanceof ColumnPixelData) {
 112                                 int pixels= ((ColumnPixelData) col).width;
 113                                 widths[i]= pixels;
 114                                 fixedWidth += pixels;
 115                         } else if (col instanceof ColumnWeightData) {
 116                                 ColumnWeightData cw= (ColumnWeightData) col;
 117                                 numberOfWeightColumns++;
 118                                 // first time, use the weight specified by the column data, otherwise use the actual width as the weight
 119                                 // int weight = firstTime ? cw.weight : tableColumns[i].getWidth();
 120                                 int weight= cw.weight;
 121                                 totalWeight += weight;
 122                         } else {
 123                                 Assert.isTrue(false, "Unknown column layout data"); //$NON-NLS-1$
 124                         }
 125                 }
 126
 127                 // Do we have columns that have a weight
 128                 if (numberOfWeightColumns > 0) {
 129                         // Now distribute the rest to the columns with weight.
 130                         int rest= width - fixedWidth;
 131                         int totalDistributed= 0;
 132                         for (int i= 0; i < size; ++i) {
 133                                 ColumnLayoutData col= (ColumnLayoutData) columns.get(i);
 134                                 if (col instanceof ColumnWeightData) {
 135                                         ColumnWeightData cw= (ColumnWeightData) col;
 136                                         // calculate weight as above
 137                                         // int weight = firstTime ? cw.weight : tableColumns[i].getWidth();
 138                                         int weight= cw.weight;
 139                                         int pixels= totalWeight == 0 ? 0 : weight * rest / totalWeight;
 140                                         if (pixels < cw.minimumWidth)
 141                                                 pixels= cw.minimumWidth;
 142                                         totalDistributed += pixels;
 143                                         widths[i]= pixels;
 144                                 }
 145                         }
 146
 147                         // Distribute any remaining pixels to columns with weight.
 148                         int diff= rest - totalDistributed;
 149                         for (int i= 0; diff > 0; ++i) {
 150                                 if (i == size)
 151                                         i= 0;
 152                                 ColumnLayoutData col= (ColumnLayoutData) columns.get(i);
 153                                 if (col instanceof ColumnWeightData) {
 154                                         ++widths[i];
 155                                         --diff;
 156                                 }
 157                         }
 158                 }
 159
 160                 if (increase) {
 161                         table.setSize(area.width, area.height);
 162                 }
 163                 for (int i= 0; i < size; i++) {
 164                         tableColumns[i].setWidth(widths[i]);
 165                 }
 166                 if (!increase) {
 167                         table.setSize(area.width, area.height);
 168                 }
 169         }
 170 }