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.logging.log4j.LogManager;import org.apache.logging.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 = LogManager.getLogger(LineWrapSupport.class);
  32
  33         ModifyListener listener = new LineWrapListener();
  34         int lineCount;
  35
  36         private StyledText textWidget;
  37         private ScrolledForm scrolledForm;
  38
  39 //      private TextViewer viewer;
  40
  41         /**
  42          * <p>Constructor for LineWrapSupport.</p>
  43          *
  44          * @param viewer a {@link org.eclipse.jface.text.TextViewer} object.
  45          * @param form a {@link org.eclipse.ui.forms.IManagedForm} object.
  46          */
  47 //      public TextViewer getViewer() {
  48 //              return viewer;
  49 //      }
  50         public LineWrapSupport(TextViewer viewer, IManagedForm form) {
  51
  52                 if (viewer == null) {
  53                         throw new IllegalArgumentException(
  54                                         "The provided TextViewer object is null."); //$NON-NLS-1$
  55                 }
  56
  57 //              this.viewer = viewer;
  58
  59                 textWidget = viewer.getTextWidget();
  60                 textWidget.addModifyListener(listener);
  61
  62                 this.lineCount = textWidget.getLinePixel(textWidget.getLineCount());
  63                 this.scrolledForm = form.getForm();
  64
  65                 logger.trace(this.getClass().getSimpleName() + " created"); //$NON-NLS-1$
  66         }
  67
  68         /**
  69          * Redraws the scrolledForm if a line wrap is detected.
  70          */
  71         private void checkLineCount() {
  72
  73                 boolean lineWrapDetected = true;
  74                 if (lineWrapDetected ) {
  75                         scrolledForm.getBody().layout();
  76                 }
  77         }
  78
  79         /**
  80          * Calls <code>checkLineCount()</code> on a modify event.
  81          *
  82          * @author p.ciardelli
  83          * @created 21.05.2008
  84          */
  85         class LineWrapListener implements ModifyListener {
  86
  87                 @Override
  88         public void modifyText(ModifyEvent e) {
  89                         checkLineCount();
  90                 }
  91         }
  92 }