/**
  * This implementation of <code>dragOver</code> provides a default drag under effect for the
  * feedback specified in <code>event.feedback</code>. The class description lists the FEEDBACK
  * constants that are applicable to the class.
  *
  * <p>For additional information see <code>DropTargetAdapter.dragOver</code>.
  *
  * <p>Subclasses that override this method should call <code>super.dragOver(event)</code> to get
  * the default drag under effect implementation.
  *
  * @param event the information associated with the drag over event
  * @see DropTargetAdapter
  * @see DropTargetEvent
  * @see DND#FEEDBACK_SELECT
  * @see DND#FEEDBACK_SCROLL
  */
 public void dragOver(DropTargetEvent event) {
   Table table = (Table) control;
   long /*int*/ handle = table.handle;
   int effect = checkEffect(event.feedback);
   Point coordinates = new Point(event.x, event.y);
   coordinates = table.toControl(coordinates);
   long /*int*/[] path = new long /*int*/[1];
   OS.gtk_tree_view_get_path_at_pos(handle, coordinates.x, coordinates.y, path, null, null, null);
   int index = -1;
   if (path[0] != 0) {
     long /*int*/ indices = OS.gtk_tree_path_get_indices(path[0]);
     if (indices != 0) {
       int[] temp = new int[1];
       OS.memmove(temp, indices, 4);
       index = temp[0];
     }
   }
   if ((effect & DND.FEEDBACK_SCROLL) == 0) {
     scrollBeginTime = 0;
     scrollIndex = -1;
   } else {
     if (index != -1 && scrollIndex == index && scrollBeginTime != 0) {
       if (System.currentTimeMillis() >= scrollBeginTime) {
         if (coordinates.y < table.getItemHeight()) {
           OS.gtk_tree_path_prev(path[0]);
         } else {
           OS.gtk_tree_path_next(path[0]);
         }
         if (path[0] != 0) {
           OS.gtk_tree_view_scroll_to_cell(handle, path[0], 0, false, 0, 0);
           OS.gtk_tree_path_free(path[0]);
           path[0] = 0;
           OS.gtk_tree_view_get_path_at_pos(
               handle, coordinates.x, coordinates.y, path, null, null, null);
         }
         scrollBeginTime = 0;
         scrollIndex = -1;
       }
     } else {
       scrollBeginTime = System.currentTimeMillis() + SCROLL_HYSTERESIS;
       scrollIndex = index;
     }
   }
   if (path[0] != 0) {
     int position = 0;
     if ((effect & DND.FEEDBACK_SELECT) != 0) position = OS.GTK_TREE_VIEW_DROP_INTO_OR_BEFORE;
     // if ((effect & DND.FEEDBACK_INSERT_BEFORE) != 0) position = OS.GTK_TREE_VIEW_DROP_BEFORE;
     // if ((effect & DND.FEEDBACK_INSERT_AFTER) != 0) position = OS.GTK_TREE_VIEW_DROP_AFTER;
     if (position != 0) {
       OS.gtk_tree_view_set_drag_dest_row(handle, path[0], OS.GTK_TREE_VIEW_DROP_INTO_OR_BEFORE);
     } else {
       OS.gtk_tree_view_set_drag_dest_row(handle, 0, OS.GTK_TREE_VIEW_DROP_BEFORE);
     }
   } else {
     OS.gtk_tree_view_set_drag_dest_row(handle, 0, OS.GTK_TREE_VIEW_DROP_BEFORE);
   }
   if (path[0] != 0) OS.gtk_tree_path_free(path[0]);
 }
 private int getHeight(final int index) {
   int result = 0;
   int columnCount = parent.getColumnCount();
   boolean singleColumn = index == 0 && columnCount == 0;
   boolean columnInRange = index >= 0 && index < columnCount;
   if (singleColumn || columnInRange) {
     result = parent.getItemHeight();
   }
   return result;
 }
 private int getTop(final int itemIndex) {
   int relativeItemIndex = itemIndex - parent.getTopIndex();
   int headerHeight = parent.getHeaderHeight();
   int itemHeight = parent.getItemHeight();
   return headerHeight + relativeItemIndex * itemHeight;
 }
 void keyDown(Event event) {
   if (row == null) return;
   switch (event.character) {
     case SWT.CR:
       notifyListeners(SWT.DefaultSelection, new Event());
       return;
   }
   int rowIndex = table.indexOf(row);
   int columnIndex = column == null ? 0 : table.indexOf(column);
   switch (event.keyCode) {
     case SWT.ARROW_UP:
       setRowColumn(Math.max(0, rowIndex - 1), columnIndex, true);
       break;
     case SWT.ARROW_DOWN:
       setRowColumn(Math.min(rowIndex + 1, table.getItemCount() - 1), columnIndex, true);
       break;
     case SWT.ARROW_LEFT:
     case SWT.ARROW_RIGHT:
       {
         int columnCount = table.getColumnCount();
         if (columnCount == 0) break;
         int[] order = table.getColumnOrder();
         int index = 0;
         while (index < order.length) {
           if (order[index] == columnIndex) break;
           index++;
         }
         if (index == order.length) index = 0;
         int leadKey = (getStyle() & SWT.RIGHT_TO_LEFT) != 0 ? SWT.ARROW_RIGHT : SWT.ARROW_LEFT;
         if (event.keyCode == leadKey) {
           setRowColumn(rowIndex, order[Math.max(0, index - 1)], true);
         } else {
           setRowColumn(rowIndex, order[Math.min(columnCount - 1, index + 1)], true);
         }
         break;
       }
     case SWT.HOME:
       setRowColumn(0, columnIndex, true);
       break;
     case SWT.END:
       {
         int i = table.getItemCount() - 1;
         setRowColumn(i, columnIndex, true);
         break;
       }
     case SWT.PAGE_UP:
       {
         int index = table.getTopIndex();
         if (index == rowIndex) {
           Rectangle rect = table.getClientArea();
           TableItem item = table.getItem(index);
           Rectangle itemRect = item.getBounds(0);
           rect.height -= itemRect.y;
           int height = table.getItemHeight();
           int page = Math.max(1, rect.height / height);
           index = Math.max(0, index - page + 1);
         }
         setRowColumn(index, columnIndex, true);
         break;
       }
     case SWT.PAGE_DOWN:
       {
         int index = table.getTopIndex();
         Rectangle rect = table.getClientArea();
         TableItem item = table.getItem(index);
         Rectangle itemRect = item.getBounds(0);
         rect.height -= itemRect.y;
         int height = table.getItemHeight();
         int page = Math.max(1, rect.height / height);
         int end = table.getItemCount() - 1;
         index = Math.min(end, index + page - 1);
         if (index == rowIndex) {
           index = Math.min(end, index + page - 1);
         }
         setRowColumn(index, columnIndex, true);
         break;
       }
   }
 }
  /** @see PreferencePage#createContents(Composite) */
  protected Control createContents(Composite ancestor) {
    Composite parent = new Composite(ancestor, SWT.NULL);
    GridLayout layout = new GridLayout();
    layout.numColumns = 2;
    layout.marginHeight = 0;
    layout.marginWidth = 0;
    parent.setLayout(layout);

    // layout the top table & its buttons
    Label label = new Label(parent, SWT.LEFT);
    label.setText(XMLCompareMessages.XMLComparePreference_topTableLabel);
    GridData data = new GridData();
    data.horizontalAlignment = GridData.FILL;
    data.horizontalSpan = 2;
    label.setLayoutData(data);

    fIdMapsTable = new Table(parent, SWT.SINGLE | SWT.BORDER | SWT.FULL_SELECTION);
    fIdMapsTable.setHeaderVisible(true);
    data = new GridData(GridData.FILL_BOTH);
    data.heightHint = fIdMapsTable.getItemHeight() * 4;
    fIdMapsTable.setLayoutData(data);
    fIdMapsTable.addSelectionListener(
        new SelectionAdapter() {
          public void widgetSelected(SelectionEvent e) {
            selectionChanged();
          }
        });

    String column2Text = XMLCompareMessages.XMLComparePreference_topTableColumn2;
    String column3Text = XMLCompareMessages.XMLComparePreference_topTableColumn3;
    ColumnLayoutData columnLayouts[] = {
      new ColumnWeightData(1),
      new ColumnPixelData(convertWidthInCharsToPixels(column2Text.length() + 2), true),
      new ColumnPixelData(convertWidthInCharsToPixels(column3Text.length() + 5), true)
    };
    TableLayout tablelayout = new TableLayout();
    fIdMapsTable.setLayout(tablelayout);
    for (int i = 0; i < 3; i++) tablelayout.addColumnData(columnLayouts[i]);
    TableColumn column = new TableColumn(fIdMapsTable, SWT.NONE);
    column.setText(XMLCompareMessages.XMLComparePreference_topTableColumn1);
    column = new TableColumn(fIdMapsTable, SWT.NONE);
    column.setText(column2Text);
    column = new TableColumn(fIdMapsTable, SWT.NONE);
    column.setText(column3Text);

    fillIdMapsTable();

    Composite buttons = new Composite(parent, SWT.NULL);
    buttons.setLayout(new GridLayout());
    data = new GridData();
    data.verticalAlignment = GridData.FILL;
    data.horizontalAlignment = GridData.FILL;
    buttons.setLayoutData(data);

    fAddIdMapButton = new Button(buttons, SWT.PUSH);
    fAddIdMapButton.setText(XMLCompareMessages.XMLComparePreference_topAdd);
    fAddIdMapButton.addSelectionListener(
        new SelectionAdapter() {
          public void widgetSelected(SelectionEvent e) {
            addIdMap(fAddIdMapButton.getShell());
          }
        });
    data = new GridData();
    data.horizontalAlignment = GridData.FILL;
    // data.heightHint = convertVerticalDLUsToPixels(IDialogConstants.BUTTON_HEIGHT);
    int widthHint = convertHorizontalDLUsToPixels(IDialogConstants.BUTTON_WIDTH);
    data.widthHint =
        Math.max(widthHint, fAddIdMapButton.computeSize(SWT.DEFAULT, SWT.DEFAULT, true).x);
    fAddIdMapButton.setLayoutData(data);

    fRenameIdMapButton = new Button(buttons, SWT.PUSH);
    fRenameIdMapButton.setText(XMLCompareMessages.XMLComparePreference_topRename);
    fRenameIdMapButton.addSelectionListener(
        new SelectionAdapter() {
          public void widgetSelected(SelectionEvent e) {
            renameIdMap(fRenameIdMapButton.getShell());
          }
        });
    data = new GridData();
    data.horizontalAlignment = GridData.FILL;
    // data.heightHint = convertVerticalDLUsToPixels(IDialogConstants.BUTTON_HEIGHT);
    widthHint = convertHorizontalDLUsToPixels(IDialogConstants.BUTTON_WIDTH);
    data.widthHint =
        Math.max(widthHint, fAddIdMapButton.computeSize(SWT.DEFAULT, SWT.DEFAULT, true).x);
    fRenameIdMapButton.setLayoutData(data);

    fRemoveIdMapButton = new Button(buttons, SWT.PUSH);
    fRemoveIdMapButton.setText(XMLCompareMessages.XMLComparePreference_topRemove);
    fRemoveIdMapButton.addSelectionListener(
        new SelectionAdapter() {
          public void widgetSelected(SelectionEvent e) {
            removeIdMap(fRemoveIdMapButton.getShell());
          }
        });
    data = new GridData();
    data.horizontalAlignment = GridData.FILL;
    // data.heightHint = convertVerticalDLUsToPixels(IDialogConstants.BUTTON_HEIGHT);
    widthHint = convertHorizontalDLUsToPixels(IDialogConstants.BUTTON_WIDTH);
    data.widthHint =
        Math.max(widthHint, fRemoveIdMapButton.computeSize(SWT.DEFAULT, SWT.DEFAULT, true).x);
    fRemoveIdMapButton.setLayoutData(data);

    createSpacer(buttons);

    fEditIdMapButton = new Button(buttons, SWT.PUSH);
    fEditIdMapButton.setText(XMLCompareMessages.XMLComparePreference_topEdit);
    fEditIdMapButton.addSelectionListener(
        new SelectionAdapter() {
          public void widgetSelected(SelectionEvent e) {
            editIdMap(fEditIdMapButton.getShell());
          }
        });
    data = new GridData();
    data.horizontalAlignment = GridData.FILL;
    // data.heightHint = convertVerticalDLUsToPixels(IDialogConstants.BUTTON_HEIGHT);
    widthHint = convertHorizontalDLUsToPixels(IDialogConstants.BUTTON_WIDTH);
    data.widthHint =
        Math.max(widthHint, fEditIdMapButton.computeSize(SWT.DEFAULT, SWT.DEFAULT, true).x);
    fEditIdMapButton.setLayoutData(data);

    // Spacer
    label = new Label(parent, SWT.LEFT);
    data = new GridData();
    data.horizontalAlignment = GridData.FILL;
    data.horizontalSpan = 2;
    label.setLayoutData(data);

    // layout the middle table & its buttons
    label = new Label(parent, SWT.LEFT);
    label.setText(XMLCompareMessages.XMLComparePreference_middleTableLabel);
    data = new GridData();
    data.horizontalAlignment = GridData.FILL;
    data.horizontalSpan = 2;
    label.setLayoutData(data);

    fMappingsTable = new Table(parent, SWT.SINGLE | SWT.BORDER | SWT.FULL_SELECTION);
    fMappingsTable.setHeaderVisible(true);
    data = new GridData(GridData.FILL_BOTH);
    data.heightHint = fMappingsTable.getItemHeight() * 4;
    data.widthHint = convertWidthInCharsToPixels(70);
    fMappingsTable.setLayoutData(data);

    column3Text = XMLCompareMessages.XMLComparePreference_middleTableColumn3;
    String column4Text = XMLCompareMessages.XMLComparePreference_middleTableColumn4;
    columnLayouts =
        new ColumnLayoutData[] {
          new ColumnWeightData(10),
          new ColumnWeightData(18),
          new ColumnPixelData(convertWidthInCharsToPixels(column3Text.length() + 1), true),
          new ColumnPixelData(convertWidthInCharsToPixels(column4Text.length() + 3), true)
        };
    tablelayout = new TableLayout();
    fMappingsTable.setLayout(tablelayout);
    for (int i = 0; i < 4; i++) tablelayout.addColumnData(columnLayouts[i]);
    column = new TableColumn(fMappingsTable, SWT.NONE);
    column.setText(XMLCompareMessages.XMLComparePreference_middleTableColumn1);
    column = new TableColumn(fMappingsTable, SWT.NONE);
    column.setText(XMLCompareMessages.XMLComparePreference_middleTableColumn2);
    column = new TableColumn(fMappingsTable, SWT.NONE);
    column.setText(column3Text);
    column = new TableColumn(fMappingsTable, SWT.NONE);
    column.setText(column4Text);

    buttons = new Composite(parent, SWT.NULL);
    buttons.setLayoutData(new GridData(GridData.VERTICAL_ALIGN_BEGINNING));
    layout = new GridLayout();
    layout.marginHeight = 0;
    layout.marginWidth = 0;
    buttons.setLayout(layout);

    fNewMappingsButton = new Button(buttons, SWT.PUSH);
    fNewMappingsButton.setLayoutData(getButtonGridData(fNewMappingsButton));
    fNewMappingsButton.setText(XMLCompareMessages.XMLComparePreference_middleNew);
    fNewMappingsButton.addSelectionListener(
        new SelectionAdapter() {
          public void widgetSelected(SelectionEvent e) {
            addMapping(fAddIdMapButton.getShell());
          }
        });

    fEditMappingsButton = new Button(buttons, SWT.PUSH);
    fEditMappingsButton.setLayoutData(getButtonGridData(fEditMappingsButton));
    fEditMappingsButton.setText(XMLCompareMessages.XMLComparePreference_middleEdit);
    fEditMappingsButton.addSelectionListener(
        new SelectionAdapter() {
          public void widgetSelected(SelectionEvent e) {
            editMapping(fEditMappingsButton.getShell());
          }
        });

    fRemoveMappingsButton = new Button(buttons, SWT.PUSH);
    fRemoveMappingsButton.setLayoutData(getButtonGridData(fRemoveMappingsButton));
    fRemoveMappingsButton.setText(XMLCompareMessages.XMLComparePreference_middleRemove);
    fRemoveMappingsButton.addSelectionListener(
        new SelectionAdapter() {
          public void widgetSelected(SelectionEvent e) {
            removeMapping(fRemoveMappingsButton.getShell());
          }
        });

    createSpacer(buttons);

    // layout the botton table & its buttons
    label = new Label(parent, SWT.LEFT);
    label.setText(XMLCompareMessages.XMLComparePreference_bottomTableLabel);
    data = new GridData();
    data.horizontalAlignment = GridData.FILL;
    data.horizontalSpan = 2;
    label.setLayoutData(data);

    fOrderedTable = new Table(parent, SWT.SINGLE | SWT.BORDER | SWT.FULL_SELECTION);
    fOrderedTable.setHeaderVisible(true);
    data = new GridData(GridData.FILL_BOTH);
    data.heightHint = fOrderedTable.getItemHeight() * 2;
    data.widthHint = convertWidthInCharsToPixels(70);
    fOrderedTable.setLayoutData(data);

    columnLayouts = new ColumnLayoutData[] {new ColumnWeightData(1), new ColumnWeightData(1)};
    tablelayout = new TableLayout();
    fOrderedTable.setLayout(tablelayout);
    for (int i = 0; i < 2; i++) tablelayout.addColumnData(columnLayouts[i]);
    column = new TableColumn(fOrderedTable, SWT.NONE);
    column.setText(XMLCompareMessages.XMLComparePreference_bottomTableColumn1);
    column = new TableColumn(fOrderedTable, SWT.NONE);
    column.setText(XMLCompareMessages.XMLComparePreference_bottomTableColumn2);

    buttons = new Composite(parent, SWT.NULL);
    buttons.setLayoutData(new GridData(GridData.VERTICAL_ALIGN_BEGINNING));
    layout = new GridLayout();
    layout.marginHeight = 0;
    layout.marginWidth = 0;
    buttons.setLayout(layout);

    fNewOrderedButton = new Button(buttons, SWT.PUSH);
    fNewOrderedButton.setLayoutData(getButtonGridData(fNewOrderedButton));
    fNewOrderedButton.setText(XMLCompareMessages.XMLComparePreference_bottomNew);
    fNewOrderedButton.addSelectionListener(
        new SelectionAdapter() {
          public void widgetSelected(SelectionEvent e) {
            addOrdered(fNewOrderedButton.getShell());
          }
        });

    fEditOrderedButton = new Button(buttons, SWT.PUSH);
    fEditOrderedButton.setLayoutData(getButtonGridData(fEditOrderedButton));
    fEditOrderedButton.setText(XMLCompareMessages.XMLComparePreference_bottomEdit);
    fEditOrderedButton.addSelectionListener(
        new SelectionAdapter() {
          public void widgetSelected(SelectionEvent e) {
            editOrdered(fEditOrderedButton.getShell());
          }
        });

    fRemoveOrderedButton = new Button(buttons, SWT.PUSH);
    fRemoveOrderedButton.setLayoutData(getButtonGridData(fRemoveOrderedButton));
    fRemoveOrderedButton.setText(XMLCompareMessages.XMLComparePreference_bottomRemove);
    fRemoveOrderedButton.addSelectionListener(
        new SelectionAdapter() {
          public void widgetSelected(SelectionEvent e) {
            removeOrdered(fRemoveOrderedButton.getShell());
          }
        });

    createSpacer(buttons);

    fIdMapsTable.setSelection(0);
    fIdMapsTable.setFocus();
    selectionChanged();

    return parent;
  }