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

   1 package net.sourceforge.phpdt.internal.ui.util;
   2
   3 import java.util.Comparator;
   4 import java.util.HashSet;
   5 import java.util.Set;
   6 import java.util.Vector;
   7
   8 //incastrix
   9 //import org.eclipse.jface.text.Assert;
  10 import org.eclipse.core.runtime.Assert;
  11 import org.eclipse.jface.viewers.ILabelProvider;
  12 import org.eclipse.swt.SWT;
  13 import org.eclipse.swt.events.DisposeEvent;
  14 import org.eclipse.swt.events.DisposeListener;
  15 import org.eclipse.swt.events.SelectionListener;
  16 import org.eclipse.swt.graphics.Image;
  17 import org.eclipse.swt.layout.GridData;
  18 import org.eclipse.swt.layout.GridLayout;
  19 import org.eclipse.swt.widgets.Composite;
  20 import org.eclipse.swt.widgets.Event;
  21 import org.eclipse.swt.widgets.Table;
  22 import org.eclipse.swt.widgets.TableItem;
  23
  24 /**
  25  * A composite widget which holds a list of elements for user selection. The
  26  * elements are sorted alphabetically. Optionally, the elements can be filtered
  27  * and duplicate entries can be hidden (folding).
  28  */
  29 public class FilteredList extends Composite {
  30
  31         public interface FilterMatcher {
  32                 /**
  33                  * Sets the filter.
  34                  *
  35                  * @param pattern
  36                  *            the filter pattern.
  37                  * @param ignoreCase
  38                  *            a flag indicating whether pattern matching is case
  39                  *            insensitive or not.
  40                  * @param ignoreWildCards
  41                  *            a flag indicating whether wildcard characters are
  42                  *            interpreted or not.
  43                  */
  44                 void setFilter(String pattern, boolean ignoreCase,
  45                                 boolean ignoreWildCards);
  46
  47                 /**
  48                  * Returns <code>true</code> if the object matches the pattern,
  49                  * <code>false</code> otherwise. <code>setFilter()</code> must have
  50                  * been called at least once prior to a call to this method.
  51                  */
  52                 boolean match(Object element);
  53         }
  54
  55         private class DefaultFilterMatcher implements FilterMatcher {
  56                 private StringMatcher fMatcher;
  57
  58                 public void setFilter(String pattern, boolean ignoreCase,
  59                                 boolean ignoreWildCards) {
  60                         fMatcher = new StringMatcher(pattern + '*', ignoreCase,
  61                                         ignoreWildCards);
  62                 }
  63
  64                 public boolean match(Object element) {
  65                         return fMatcher.match(fRenderer.getText(element));
  66                 }
  67         }
  68
  69         private Table fList;
  70
  71         private ILabelProvider fRenderer;
  72
  73         private boolean fMatchEmtpyString = true;
  74
  75         private boolean fIgnoreCase;
  76
  77         private boolean fAllowDuplicates;
  78
  79         private String fFilter = ""; //$NON-NLS-1$
  80
  81         private TwoArrayQuickSorter fSorter;
  82
  83         private Object[] fElements = new Object[0];
  84
  85         private Label[] fLabels;
  86
  87         private Vector fImages = new Vector();
  88
  89         private int[] fFoldedIndices;
  90
  91         private int fFoldedCount;
  92
  93         private int[] fFilteredIndices;
  94
  95         private int fFilteredCount;
  96
  97         private FilterMatcher fFilterMatcher = new DefaultFilterMatcher();
  98
  99         private Comparator fComparator;
 100
 101         private static class Label {
 102                 public final String string;
 103
 104                 public final Image image;
 105
 106                 public Label(String string, Image image) {
 107                         this.string = string;
 108                         this.image = image;
 109                 }
 110
 111                 public boolean equals(Label label) {
 112                         if (label == null)
 113                                 return false;
 114
 115                         return string.equals(label.string) && image.equals(label.image);
 116                 }
 117         }
 118
 119         private final class LabelComparator implements Comparator {
 120                 private boolean fIgnoreCase;
 121
 122                 LabelComparator(boolean ignoreCase) {
 123                         fIgnoreCase = ignoreCase;
 124                 }
 125
 126                 public int compare(Object left, Object right) {
 127                         Label leftLabel = (Label) left;
 128                         Label rightLabel = (Label) right;
 129
 130                         int value;
 131
 132                         if (fComparator == null) {
 133                                 value = fIgnoreCase ? leftLabel.string
 134                                                 .compareToIgnoreCase(rightLabel.string)
 135                                                 : leftLabel.string.compareTo(rightLabel.string);
 136                         } else {
 137                                 value = fComparator
 138                                                 .compare(leftLabel.string, rightLabel.string);
 139                         }
 140
 141                         if (value != 0)
 142                                 return value;
 143
 144                         // images are allowed to be null
 145                         if (leftLabel.image == null) {
 146                                 return (rightLabel.image == null) ? 0 : -1;
 147                         } else if (rightLabel.image == null) {
 148                                 return +1;
 149                         } else {
 150                                 return fImages.indexOf(leftLabel.image)
 151                                                 - fImages.indexOf(rightLabel.image);
 152                         }
 153                 }
 154
 155         }
 156
 157         /**
 158          * Constructs a new instance of a filtered list.
 159          *
 160          * @param parent
 161          *            the parent composite.
 162          * @param style
 163          *            the widget style.
 164          * @param renderer
 165          *            the label renderer.
 166          * @param ignoreCase
 167          *            specifies whether sorting and folding is case sensitive.
 168          * @param allowDuplicates
 169          *            specifies whether folding of duplicates is desired.
 170          * @param matchEmptyString
 171          *            specifies whether empty filter strings should filter
 172          *            everything or nothing.
 173          */
 174         public FilteredList(Composite parent, int style, ILabelProvider renderer,
 175                         boolean ignoreCase, boolean allowDuplicates,
 176                         boolean matchEmptyString) {
 177                 super(parent, SWT.NONE);
 178
 179                 GridLayout layout = new GridLayout();
 180                 layout.marginHeight = 0;
 181                 layout.marginWidth = 0;
 182                 setLayout(layout);
 183
 184                 fList = new Table(this, style);
 185                 fList.setLayoutData(new GridData(GridData.FILL_BOTH));
 186                 fList.addDisposeListener(new DisposeListener() {
 187                         public void widgetDisposed(DisposeEvent e) {
 188                                 fRenderer.dispose();
 189                         }
 190                 });
 191
 192                 fRenderer = renderer;
 193                 fIgnoreCase = ignoreCase;
 194                 fSorter = new TwoArrayQuickSorter(new LabelComparator(ignoreCase));
 195                 fAllowDuplicates = allowDuplicates;
 196                 fMatchEmtpyString = matchEmptyString;
 197         }
 198
 199         /**
 200          * Sets the list of elements.
 201          *
 202          * @param elements
 203          *            the elements to be shown in the list.
 204          */
 205         public void setElements(Object[] elements) {
 206                 if (elements == null) {
 207                         fElements = new Object[0];
 208                 } else {
 209                         // copy list for sorting
 210                         fElements = new Object[elements.length];
 211                         System.arraycopy(elements, 0, fElements, 0, elements.length);
 212                 }
 213
 214                 int length = fElements.length;
 215
 216                 // fill labels
 217                 fLabels = new Label[length];
 218                 Set imageSet = new HashSet();
 219                 for (int i = 0; i != length; i++) {
 220                         String text = fRenderer.getText(fElements[i]);
 221                         Image image = fRenderer.getImage(fElements[i]);
 222
 223                         fLabels[i] = new Label(text, image);
 224                         imageSet.add(image);
 225                 }
 226                 fImages.clear();
 227                 fImages.addAll(imageSet);
 228
 229                 fSorter.sort(fLabels, fElements);
 230
 231                 fFilteredIndices = new int[length];
 232                 fFilteredCount = filter();
 233
 234                 fFoldedIndices = new int[length];
 235                 fFoldedCount = fold();
 236
 237                 updateList();
 238         }
 239
 240         /**
 241          * Tests if the list (before folding and filtering) is empty.
 242          *
 243          * @return returns <code>true</code> if the list is empty,
 244          *         <code>false</code> otherwise.
 245          */
 246         public boolean isEmpty() {
 247                 return (fElements == null) || (fElements.length == 0);
 248         }
 249
 250         /**
 251          * Sets the filter matcher.
 252          */
 253 //      public void setFilterMatcher(FilterMatcher filterMatcher) {
 254 //              Assert.isNotNull(filterMatcher);
 255 //              fFilterMatcher = filterMatcher;
 256 //      }
 257
 258         /**
 259          * Sets a custom comparator for sorting the list.
 260          */
 261         public void setComparator(Comparator comparator) {
 262                 Assert.isNotNull(comparator);
 263                 fComparator = comparator;
 264         }
 265
 266         /**
 267          * Adds a selection listener to the list.
 268          *
 269          * @param listener
 270          *            the selection listener to be added.
 271          */
 272         public void addSelectionListener(SelectionListener listener) {
 273                 fList.addSelectionListener(listener);
 274         }
 275
 276         /**
 277          * Removes a selection listener from the list.
 278          *
 279          * @param listener
 280          *            the selection listener to be removed.
 281          */
 282         public void removeSelectionListener(SelectionListener listener) {
 283                 fList.removeSelectionListener(listener);
 284         }
 285
 286         /**
 287          * Sets the selection of the list.
 288          *
 289          * @param selection
 290          *            an array of indices specifying the selection.
 291          */
 292         public void setSelection(int[] selection) {
 293                 fList.setSelection(selection);
 294         }
 295
 296         /**
 297          * Returns the selection of the list.
 298          *
 299          * @return returns an array of indices specifying the current selection.
 300          */
 301         public int[] getSelectionIndices() {
 302                 return fList.getSelectionIndices();
 303         }
 304
 305         /**
 306          * Returns the selection of the list. This is a convenience function for
 307          * <code>getSelectionIndices()</code>.
 308          *
 309          * @return returns the index of the selection, -1 for no selection.
 310          */
 311         public int getSelectionIndex() {
 312                 return fList.getSelectionIndex();
 313         }
 314
 315         /**
 316          * Sets the selection of the list.
 317          *
 318          * @param elements
 319          *            the array of elements to be selected.
 320          */
 321         public void setSelection(Object[] elements) {
 322                 if ((elements == null) || (fElements == null))
 323                         return;
 324
 325                 // fill indices
 326                 int[] indices = new int[elements.length];
 327                 for (int i = 0; i != elements.length; i++) {
 328                         int j;
 329                         for (j = 0; j != fFoldedCount; j++) {
 330                                 int max = (j == fFoldedCount - 1) ? fFilteredCount
 331                                                 : fFoldedIndices[j + 1];
 332
 333                                 int l;
 334                                 for (l = fFoldedIndices[j]; l != max; l++) {
 335                                         // found matching element?
 336                                         if (fElements[fFilteredIndices[l]].equals(elements[i])) {
 337                                                 indices[i] = j;
 338                                                 break;
 339                                         }
 340                                 }
 341
 342                                 if (l != max)
 343                                         break;
 344                         }
 345
 346                         // not found
 347                         if (j == fFoldedCount)
 348                                 indices[i] = 0;
 349                 }
 350
 351                 fList.setSelection(indices);
 352         }
 353
 354         /**
 355          * Returns an array of the selected elements. The type of the elements
 356          * returned in the list are the same as the ones passed with
 357          * <code>setElements</code>. The array does not contain the rendered
 358          * strings.
 359          *
 360          * @return returns the array of selected elements.
 361          */
 362         public Object[] getSelection() {
 363                 if (fList.isDisposed() || (fList.getSelectionCount() == 0))
 364                         return new Object[0];
 365
 366                 int[] indices = fList.getSelectionIndices();
 367                 Object[] elements = new Object[indices.length];
 368
 369                 for (int i = 0; i != indices.length; i++)
 370                         elements[i] = fElements[fFilteredIndices[fFoldedIndices[indices[i]]]];
 371
 372                 return elements;
 373         }
 374
 375         /**
 376          * Sets the filter pattern. Current only prefix filter patterns are
 377          * supported.
 378          *
 379          * @param filter
 380          *            the filter pattern.
 381          */
 382         public void setFilter(String filter) {
 383                 fFilter = (filter == null) ? "" : filter; //$NON-NLS-1$
 384
 385                 fFilteredCount = filter();
 386                 fFoldedCount = fold();
 387                 updateList();
 388         }
 389
 390         /**
 391          * Returns the filter pattern.
 392          *
 393          * @return returns the filter pattern.
 394          */
 395         public String getFilter() {
 396                 return fFilter;
 397         }
 398
 399         /**
 400          * Returns all elements which are folded together to one entry in the list.
 401          *
 402          * @param index
 403          *            the index selecting the entry in the list.
 404          * @return returns an array of elements folded together, <code>null</code>
 405          *         if index is out of range.
 406          */
 407         public Object[] getFoldedElements(int index) {
 408                 if ((index < 0) || (index >= fFoldedCount))
 409                         return null;
 410
 411                 int start = fFoldedIndices[index];
 412                 int count = (index == fFoldedCount - 1) ? fFilteredCount - start
 413                                 : fFoldedIndices[index + 1] - start;
 414
 415                 Object[] elements = new Object[count];
 416                 for (int i = 0; i != count; i++)
 417                         elements[i] = fElements[fFilteredIndices[start + i]];
 418
 419                 return elements;
 420         }
 421
 422         /*
 423          * Folds duplicate entries. Two elements are considered as a pair of
 424          * duplicates if they coiincide in the rendered string and image. @return
 425          * returns the number of elements after folding.
 426          */
 427         private int fold() {
 428                 if (fAllowDuplicates) {
 429                         for (int i = 0; i != fFilteredCount; i++)
 430                                 fFoldedIndices[i] = i; // identity mapping
 431
 432                         return fFilteredCount;
 433
 434                 } else {
 435                         int k = 0;
 436                         Label last = null;
 437                         for (int i = 0; i != fFilteredCount; i++) {
 438                                 int j = fFilteredIndices[i];
 439
 440                                 Label current = fLabels[j];
 441                                 if (!current.equals(last)) {
 442                                         fFoldedIndices[k] = i;
 443                                         k++;
 444                                         last = current;
 445                                 }
 446                         }
 447                         return k;
 448                 }
 449         }
 450
 451         /*
 452          * Filters the list with the filter pattern. @return returns the number of
 453          * elements after filtering.
 454          */
 455         private int filter() {
 456                 if (((fFilter == null) || (fFilter.length() == 0))
 457                                 && !fMatchEmtpyString)
 458                         return 0;
 459
 460                 fFilterMatcher.setFilter(fFilter.trim(), fIgnoreCase, false);
 461
 462                 int k = 0;
 463                 for (int i = 0; i != fElements.length; i++) {
 464                         if (fFilterMatcher.match(fElements[i]))
 465                                 fFilteredIndices[k++] = i;
 466                 }
 467
 468                 return k;
 469         }
 470
 471         /*
 472          * Updates the list widget.
 473          */
 474         private void updateList() {
 475                 if (fList.isDisposed())
 476                         return;
 477
 478                 fList.setRedraw(false);
 479
 480                 // resize table
 481                 int itemCount = fList.getItemCount();
 482                 if (fFoldedCount < itemCount)
 483                         fList.remove(0, itemCount - fFoldedCount - 1);
 484                 else if (fFoldedCount > itemCount)
 485                         for (int i = 0; i != fFoldedCount - itemCount; i++)
 486                                 new TableItem(fList, SWT.NONE);
 487
 488                 // fill table
 489                 TableItem[] items = fList.getItems();
 490                 for (int i = 0; i != fFoldedCount; i++) {
 491                         TableItem item = items[i];
 492                         Label label = fLabels[fFilteredIndices[fFoldedIndices[i]]];
 493
 494                         item.setText(label.string);
 495                         item.setImage(label.image);
 496                 }
 497
 498                 // select first item if any
 499                 if (fList.getItemCount() > 0)
 500                         fList.setSelection(0);
 501
 502                 fList.setRedraw(true);
 503                 fList.notifyListeners(SWT.Selection, new Event());
 504         }
 505
 506 }