eu.etaxonomy.taxeditor.editor/src/main/java/eu/etaxonomy/taxeditor/editor/name/container/LineWrapSupport.java

   1 /**
   2 * Copyright (C) 2007 EDIT
   3 * European Distributed Institute of Taxonomy
   4 * http://www.e-taxonomy.eu
   5 *
   6 * The contents of this file are subject to the Mozilla Public License Version 1.1
   7 * See LICENSE.TXT at the top of this package for the full license terms.
   8 */
   9 package eu.etaxonomy.taxeditor.editor.name.container;
  10
  11 import org.apache.log4j.Logger;
  12 import org.eclipse.jface.text.TextViewer;
  13 import org.eclipse.swt.custom.StyledText;
  14 import org.eclipse.swt.events.ModifyEvent;
  15 import org.eclipse.swt.events.ModifyListener;
  16 import org.eclipse.ui.forms.IManagedForm;
  17 import org.eclipse.ui.forms.widgets.ScrolledForm;
  18
  19 /**
  20  * Checks whether the ScrolledForm a TextViewer is on needs to be
  21  *  redrawn because of a new line break or the removal of an existing
  22  *  one ...
  23  *  <p>
  24  *  ... in theory, anyway. Until I figure out how to detect a word wrap,
  25  *   the ScrolledForm is redrawn with every modify event.
  26  *
  27  * @author p.ciardelli
  28  * @created 19.05.2008
  29  */
  30 public class LineWrapSupport {
  31         private static final Logger logger = Logger
  32                         .getLogger(LineWrapSupport.class);
  33
  34         ModifyListener listener = new LineWrapListener();
  35         int lineCount;
  36
  37         private StyledText textWidget;
  38         private ScrolledForm scrolledForm;
  39
  40 //      private TextViewer viewer;
  41
  42         /**
  43          * <p>Constructor for LineWrapSupport.</p>
  44          *
  45          * @param viewer a {@link org.eclipse.jface.text.TextViewer} object.
  46          * @param form a {@link org.eclipse.ui.forms.IManagedForm} object.
  47          */
  48 //      public TextViewer getViewer() {
  49 //              return viewer;
  50 //      }
  51         public LineWrapSupport(TextViewer viewer, IManagedForm form) {
  52
  53                 if (viewer == null) {
  54                         throw new IllegalArgumentException(
  55                                         "The provided TextViewer object is null."); //$NON-NLS-1$
  56                 }
  57
  58 //              this.viewer = viewer;
  59
  60                 textWidget = viewer.getTextWidget();
  61                 textWidget.addModifyListener(listener);
  62
  63                 this.lineCount = textWidget.getLinePixel(textWidget.getLineCount());
  64                 this.scrolledForm = form.getForm();
  65
  66                 logger.trace(this.getClass().getSimpleName() + " created"); //$NON-NLS-1$
  67         }
  68
  69         /**
  70          * Redraws the scrolledForm if a line wrap is detected.
  71          */
  72         private void checkLineCount() {
  73
  74                 boolean lineWrapDetected = true;
  75                 if (lineWrapDetected ) {
  76                         scrolledForm.getBody().layout();
  77                 }
  78         }
  79
  80         /**
  81          * Calls <code>checkLineCount()</code> on a modify event.
  82          *
  83          * @author p.ciardelli
  84          * @created 21.05.2008
  85          */
  86         class LineWrapListener implements ModifyListener {
  87
  88                 public void modifyText(ModifyEvent e) {
  89                         checkLineCount();
  90                 }
  91         }
  92 }