* Ext GWT - Ext for GWT

* Copyright(c) 2007, 2008, Ext JS, LLC.

* licensing@extjs.com

*

* http://extjs.com/license

*/

* <p>

* This class encapsulates the user interface of an {@link Grid}. Methods of

* this class may be used to access user interface elements to enable special

* display effects. Do not change the DOM structure of the user interface.

* </p>

* <p>

* This class does not provide ways to manipulate the underlying data. The data

* model of a Grid is held in an {@link ListStore}.

* </p>

*

*/

  class GridSplitBar extends BoxComponent {

    private int startX;

    private int colIndex;

    private boolean dragging;

    private Draggable d;

    private DragListener listener = new DragListener() {

      @Override

      public void dragEnd(DragEvent de) {

        onDragEnd(de);

      }

      @Override

      public void dragStart(DragEvent de) {

        onDragStart(de);

      }

    };

    protected void onDragEnd(DragEvent e) {

      dragging = false;

      headerDisabled = false;

      setStyleAttribute("borderLeft", "none");

      el().setStyleAttribute("opacity", "0");

      el().setWidth(splitterWidth);

      bar.el().setVisibility(false);

      int endX = e.event.getClientX();

      int diff = endX - startX;

      onColumnSplitterMoved(colIndex, cm.getColumnWidth(colIndex) + diff);

    }

    protected void onDragStart(DragEvent e) {

      headerDisabled = true;

      dragging = true;

      setStyleAttribute("borderLeft", "1px solid black");

      setStyleAttribute("cursor", "default");

      el().setStyleAttribute("opacity", "1");

      el().setWidth(1);

      startX = e.event.getClientX();

      int cols = cm.getColumnCount();

      for (int i = 0, len = cols; i < len; i++) {

        Element hd = getHeaderCell(i);

        if (hd != null) {

          Region rr = El.fly(hd).getRegion();

          if (startX > rr.right - 5 && startX < rr.right + 5) {

            colIndex = findHeaderIndex(hd);

            break;

          }

        }

      }

      if (colIndex > -1) {

        Element c = getHeaderCell(colIndex);

        int x = startX;

        int minx = x - fly((com.google.gwt.user.client.Element) c).getX()

            - grid.getMinColumnWidth();

        int maxx = (grid.el().getX() + grid.el().getWidth()) - e.event.getClientX();

        d.setXConstraint(minx, maxx);

      }

    }

    protected void onMouseMove(Event event) {

      if (dragging) {

        return;

      }

      int x = event.getClientX();

      Region r = activeHdRegion;

      int hw = splitterWidth;

      el().setY(grid.el().getY());

      el().setHeight(grid.getHeight());

      Style ss = getElement().getStyle();

      if (x - r.left <= hw && cm.isResizable(activeHdIndex - 1)) {

        bar.el().setVisibility(true);

        el().setX(r.left);

        ss.setProperty("cursor", GXT.isSafari ? "e-resize" : "col-resize");

      } else if (r.right - x <= hw && cm.isResizable(activeHdIndex)) {

        el().setX(r.right - (hw / 2));

        bar.el().setVisibility(true);

        ss.setProperty("cursor", GXT.isSafari ? "w-resize" : "col-resize");

      } else {

        bar.el().setVisibility(false);

        ss.setProperty("cursor", "");

      }

    }

    @Override

    protected void onRender(com.google.gwt.user.client.Element target, int index) {

      super.onRender(target, index);

      setElement(DOM.createDiv(), target, index);

      el().setStyleAttribute("cursor", "col-resize");

      setStyleAttribute("position", "absolute");

      setWidth(5);

      el().setVisibility(false);

      el().setStyleAttribute("backgroundColor", "white");

      el().setStyleAttribute("opacity", "0");

      d = new Draggable(this);

      d.setUseProxy(false);

      d.setConstrainVertical(true);

      d.addDragListener(listener);

    }

  }

  // config

  protected boolean enableRowBody;

  protected GridViewConfig viewConfig;

  protected Grid grid;

  protected ColumnModel cm;

  protected ListStore ds;

  protected String emptyText = "&nbsp;";

  protected boolean deferEmptyText;

  protected boolean enableHdMenu = true;

  protected boolean autoFill;

  protected boolean forceFit;

  protected int scrollOffset = 19;

  protected boolean userResized;

  protected int borderWidth = 2;

  protected int splitterWidth = 5;

  protected GridTemplates templates;

  // elements

  protected El el, mainWrap, mainHd, innerHd, scroller, mainBody, focusEl;

  protected int activeHdIndex;

  private boolean showDirtyCells = true;

  private String cellSelector = "td.x-grid3-cell";

  private String hdStyle = "x-grid3-hd";

  private String rowSelector = "div.x-grid3-row";

  private GridSplitBar bar;

  private Menu menu;

  private SortInfo sortState;

  private int lastViewWidth;

  private boolean headerDisabled;

  private Element activeHd;

  private Region activeHdRegion;

  private Element activeHdBtn;

  private StoreListener listener;

  private EventListener headerListener;

  private EventListener scrollListener;

  private Listener columnListener;

  private int cellSelectorDepth = 4;

  private int rowSelectorDepth = 10;

  private Element overRow;

  /**

   * Returns the cell.

   *

   * @param elem the cell element or a child element

   * @return the cell element

   */

  public Element findCell(Element elem) {

    if (elem == null) {

      return null;

    }

    return fly(elem).findParentElement(cellSelector, cellSelectorDepth);

  }

  /**

   * Returns the cell index.

   *

   * @param elem the cell or child element

   * @param requiredStyle an optional required style name

   * @return the cell index or -1 if not found

   */

  public int findCellIndex(Element elem, String requiredStyle) {

    Element cell = findCell(elem);

    if (cell != null && (requiredStyle == null || fly(cell).hasStyleName(requiredStyle))) {

      return getCellIndex(cell);

    }

    return -1;

  }

  /**

   * Returns the row element.

   *

   * @param el the row element or any child element

   * @return the matching row element

   */

  public Element findRow(Element el) {

    if (el == null) {

      return null;

    }

    return fly(el).findParentElement(rowSelector, rowSelectorDepth);

  }

  /**

   * Returns the row index.

   *

   * @param elem the row or child of the row element

   * @return the index

   */

  public int findRowIndex(Element elem) {

    Element r = findRow(elem);

    return r != null ? r.getPropertyInt("rowIndex") : -1;

  }

  /**

   * Focus the cell and scrolls into view.

   *

   * @param rowIndex the row index

   * @param colIndex the column index

   * @param hscroll true to scroll horizontally

   */

  public void focusCell(int rowIndex, int colIndex, boolean hscroll) {

    Point xy = ensureVisible(rowIndex, colIndex, hscroll);

    if (xy != null) {

      focusEl.setXY(xy);

      if (GXT.isGecko) {

        focusEl.setFocus(true);

      } else {

        DeferredCommand.addCommand(new Command() {

          public void execute() {

            focusEl.setFocus(true);

          }

        });

      }

    }

  }

  /**

   * Focus the row and scrolls into view.

   *

   * @param rowIndex the row index

   */

  public void focusRow(int rowIndex) {

    focusCell(rowIndex, 0, true);

  }

  /**

   * Returns the grid's body element.

   *

   * @return the body element

   */

  public El getBody() {

    return scroller;

  }

  /**

   * Returns the grid's &lt;TD> HtmlElement at the specified coordinates.

   *

   * @param row the row index in which to find the cell

   * @param col the column index of the cell

   * @return the &lt;TD> at the specified coordinates

   */

  public Element getCell(int row, int col) {

    return getRow(row).getElementsByTagName("td").getItem(col);

  }

  /**

   * Returns the cell selector depth.

   *

   * @return the cell selector depth

   */

  public int getCellSelectorDepth() {

    return cellSelectorDepth;

  }

  /**

   * Returns the empty text.

   *

   * @return the empty text

   */

  public String getEmptyText() {

    return emptyText;

  }

  /**

   * Returns the &lt;TD> HtmlElement which represents the Grid's header cell for

   * the specified column index.

   *

   * @param index the column index

   * @return the &lt;TD> element.

   */

  public Element getHeaderCell(int index) {

    return mainHd.dom.getElementsByTagName("td").getItem(index);

  }

  /**

   * Return the &lt;TR> HtmlElement which represents a Grid row for the

   * specified index.

   *

   * @param row the row index

   * @return the &lt;TR> element

   */

  public Element getRow(int row) {

    Element[] rows = getRows();

    if (row < rows.length) {

      return rows[row];

    }

    return null;

  }

  /**

   * Returns the row selector depth.

   *

   * @return the row selector depth

   */

  public int getRowSelectorDepth() {

    return rowSelectorDepth;

  }

  /**

   * Returns the view config.

   *

   * @return the view config

   */

  public GridViewConfig getViewConfig() {

    return viewConfig;

  }

  /**

   * Returns true if auto fill is enabled.

   *

   * @return true for auto fill

   */

  public boolean isAutoFill() {

    return autoFill;

  }

  /**

   * Returns true if force fit is enabled.

   *

   * @return true for force fit

   */

  public boolean isForceFit() {

    return forceFit;

  }

  /**

   * Returns true if dirty cell markers are enabled.

   *

   * @return true of dirty cell markers

   */

  public boolean isShowDirtyCells() {

    return showDirtyCells;

  }

  public void layout() {

    if (mainBody == null) {

      return;

    }

    El c = grid.el();

    Size csize = c.getStyleSize();

    int vw = csize.width;

    int vh = 0;

    if (vw < 10 || csize.height < 20) {

      return;

    }

    resize();

    if (forceFit) {

      if (lastViewWidth != vw) {

        fitColumns(false, false, -1);

        lastViewWidth = vw;

      }

    } else {

      autoExpand(false);

      syncHeaderScroll();

    }

    templateOnLayout(vw, vh);

  }

  /**

   * Rebuilds the grid using its current configuration and data.

   *

   * @param headerToo true to refresh the header

   */

  public void refresh(boolean headerToo) {

    if (grid instanceof EditorGrid) {

      ((EditorGrid) grid).stopEditing(true);

    }

    String result = renderBody();

    mainBody.setInnerHtml(result);

    if (headerToo) {

      updateHeaders();

    }

    processRows(0, true);

    layout();

    applyEmptyText();

    fireEvent(Events.Refresh);

  }

  /**

   * Scrolls the grid to the top.

   */

  public void scrollToTop() {

    scroller.setScrollTop(0);

    scroller.setScrollLeft(0);

  }

  /**

   * True to auto expand the columns to fit the grid <b>when the grid is

   * created</b>.

   *

   * @param autoFill true to expand

   */

  public void setAutoFill(boolean autoFill) {

    this.autoFill = autoFill;

  }

  /**

   * The number of levels to search for cells in event delegation (defaults to

   * 4).

   *

   * @param cellSelectorDepth the cell selector depth

   */

  public void setCellSelectorDepth(int cellSelectorDepth) {

    this.cellSelectorDepth = cellSelectorDepth;

  }

  /**

   * Default text to display in the grid body when no rows are available

   * (defaults to '').

   *

   * @param emptyText the empty text

   */

  public void setEmptyText(String emptyText) {

    this.emptyText = emptyText;

  }

  /**

   * True to auto expand/contract the size of the columns to fit the grid width

   * and prevent horizontal scrolling.

   *

   * @param forceFit true to force fit

   */

  public void setForceFit(boolean forceFit) {

    this.forceFit = forceFit;

  }

  /**

   * The number of levels to search for rows in event delegation (defaults to

   * 10).

   *

   * @param rowSelectorDepth the row selector depth

   */

  public void setRowSelectorDepth(int rowSelectorDepth) {

    this.rowSelectorDepth = rowSelectorDepth;

  }

  /**

   * True to display a red triangle in the upper left corner of any cells which

   * are "dirty" as defined by any existing records in the data store (defaults

   * to true).

   *

   * @param showDirtyCells true to display the dirty flag

   */

  public void setShowDirtyCells(boolean showDirtyCells) {

    this.showDirtyCells = showDirtyCells;

  }

  /**

   * Sets the view config.

   *

   * @param viewConfig the view config

   */

  public void setViewConfig(GridViewConfig viewConfig) {

    this.viewConfig = viewConfig;

  }

  protected void addRowStyle(Element elem, String style) {

    if (elem != null) {

      fly(elem).addStyleName(style);

    }

  }

  protected void afterRender() {

    applyEmptyText();

  }

  protected void autoExpand(boolean preventUpdate) {

    if (!userResized && grid.getAutoExpandColumn() != null) {

      int tw = cm.getTotalWidth(false);

      int aw = grid.getWidth(true) - scrollOffset;

      if (tw != aw) {

        int ci = cm.getIndexById(grid.getAutoExpandColumn());

        int currentWidth = cm.getColumnWidth(ci);

        int cw = Math.min(Math.max(((aw - tw) + currentWidth), grid.getAutoExpandMin()),

            grid.getAutoExpandMax());

        if (cw != currentWidth) {

          cm.setColumnWidth(ci, cw, true);

          if (!preventUpdate) {

            updateColumnWidth(ci, cw);

          }

        }

      }

    }

  }

  protected Menu createContextMenu(final int colIndex) {

    final Menu menu = new Menu();

    if (cm.isSortable(colIndex)) {

      MenuItem item = new MenuItem();

      item.setText(GXT.MESSAGES.gridView_sortAscText());

      item.setIconStyle("my-icon-asc");

      item.addSelectionListener(new SelectionListener<ComponentEvent>() {

        public void componentSelected(ComponentEvent ce) {

          ds.sort(cm.getDataIndex(colIndex), SortDir.ASC);

        }

      });

      menu.add(item);

      item = new MenuItem();

      item.setText(GXT.MESSAGES.gridView_sortDescText());

      item.setIconStyle("my-icon-desc");

      item.addSelectionListener(new SelectionListener<ComponentEvent>() {

        public void componentSelected(ComponentEvent ce) {

          ds.sort(cm.getDataIndex(colIndex), SortDir.DESC);

        }

      });

      menu.add(item);

    }

    MenuItem columns = new MenuItem();

    columns.setText(GXT.MESSAGES.gridView_columnsText());

    columns.setIconStyle("x-cols-icon");

    final Menu columnMenu = new Menu();

    int cols = cm.getColumnCount();

    for (int i = 0; i < cols; i++) {

      if (cm.getColumnHeader(i) == null || cm.getColumnHeader(i).equals("") || cm.isFixed(i)) {

        continue;

      }

      final int fcol = i;

      final CheckMenuItem check = new CheckMenuItem();

      check.setHideOnClick(false);

      check.setText(cm.getColumnHeader(i));

      check.setChecked(!cm.isHidden(i));

      check.addSelectionListener(new SelectionListener<ComponentEvent>() {

        public void componentSelected(ComponentEvent ce) {

          cm.setHidden(fcol, !cm.isHidden(fcol));

          restrictMenu(columnMenu);

        }

      });

      columnMenu.add(check);

    }

    restrictMenu(columnMenu);

    columns.setSubMenu(columnMenu);

    menu.add(columns);

    return menu;

  }

  protected void deleteRows(ListStore store, int firstRow, int lastRow) {

    if (store.getCount() < 1) {

      refresh(false);

      return;

    }

    removeRows(firstRow, lastRow);

  }

  protected void doAttach() {

    DOM.setEventListener(mainHd.dom, headerListener);

    if (bar != null) {

      DOM.setEventListener(bar.getElement(), bar);

    }

    if (scroller != null) {

      DOM.setEventListener(scroller.dom, scrollListener);

    }

  }

  protected void doDetach() {

    DOM.setEventListener(mainHd.dom, null);

    if (bar != null) {

      DOM.setEventListener(bar.getElement(), null);

    }

    if (scroller != null) {

      DOM.setEventListener(scroller.dom, null);

    }

  }

  protected String doRender(List<ColumnData> cs, List rows, int startRow, int colCount,

      boolean stripe) {

    int last = colCount - 1;

    String tstyle = "width:" + getTotalWidth() + ";";

    StringBuilder buf = new StringBuilder();

    StringBuilder cb = new StringBuilder();

    for (int j = 0; j < rows.size(); j++) {

      ModelData model = (ModelData) rows.get(j);

      Record r = ds.hasRecord(model) ? ds.getRecord(model) : null;

      int rowIndex = (j + startRow);

      for (int i = 0; i < colCount; i++) {

        ColumnData c = cs.get(i);

        c.css = c.css == null ? "" : c.css;

        String rv = getRenderedValue(c, rowIndex, i, model, c.id);

        String css = (i == 0 ? "x-grid-cell-first " : (i == last ? "x-grid3-cell-last " : " "))

            + " " + (c.css == null ? "" : c.css);

        String attr = c.cellAttr != null ? c.cellAttr : "";

        String cellAttr = c.cellAttr != null ? c.cellAttr : "";

        if (showDirtyCells && r != null && r.getChanges().containsKey(c.id)) {

          css += " x-grid3-dirty-cell";

        }

        cb.append("<td class=\"x-grid3-col x-grid3-cell x-grid3-td-" + c.id + " " + css

            + "\" style=\"" + c.style + "\" tabIndex=0 " + cellAttr

            + "><div class=\"x-grid3-cell-inner x-grid3-col-" + c.id + "\" " + attr + ">" + rv

            + "</div></td>");

      }

      String alt = "";

      if (stripe && ((rowIndex + 1) % 2 == 0)) {

        alt += " x-grid3-row-alt";

      }

      if (showDirtyCells && r != null && r.isDirty()) {

        alt += " x-grid3-dirty-row";

      }

      if (viewConfig != null) {

        alt += " " + viewConfig.getRowStyle(model, rowIndex, ds);

      }

      buf.append("<div class=\"x-grid3-row "

          + alt

          + "\" style=\""

          + tstyle

          + "\"><table class=x-grid3-row-table border=0 cellspacing=0 cellpadding=0 style=\""

          + tstyle

          + "\"><tbody><tr>"

          + cb.toString()

          + "</tr>"

          + (enableRowBody

              ? ("<tr class=x-grid3-row-body-tr style=\"\"><td colspan=" + colCount + " class=x-grid3-body-cell tabIndex=0><div class=x-grid3-row-body>${body}</div></td></tr>")

              : "") + "</tbody></table></div>");

      cb = new StringBuilder();

    }

    return buf.toString();

  }

  protected Point ensureVisible(int row, int col, boolean hscroll) {

    if (row < 0 || row > ds.getCount()) {

      return null;

    }

    if (col == -1) {

      col = 0;

    }

    Element rowEl = getRow(row);

    Element cellEl = null;

    if (!(!hscroll && col == 0)) {

      while (cm.isHidden(col)) {

        col++;

      }

      cellEl = getCell(row, col);

    }

    if (rowEl == null) {

      return null;

    }

    Element c = scroller.dom;

    int ctop = 0;

    Element p = rowEl, stope = el.dom;

    while (p != null && p != stope) {

      ctop += p.getOffsetTop();

      p = p.getOffsetParent().cast();

    }

    ctop -= mainHd.dom.getOffsetHeight();

    int cbot = ctop + rowEl.getOffsetHeight();

    int ch = c.getOffsetHeight();

    int stop = c.getScrollTop();

    int sbot = stop + ch;

    if (ctop < stop) {

      c.setScrollTop(ctop);

    } else if (cbot > sbot) {

      if (hscroll && (cm.getTotalWidth() > scroller.getWidth() - scrollOffset)) {

        cbot += scrollOffset;

      }

      c.setScrollTop(cbot -= ch);

    }

    if (hscroll) {

      int cleft = cellEl.getOffsetLeft();

      int cright = cleft + cellEl.getOffsetWidth();

      int sleft = c.getScrollLeft();

      int sright = sleft + c.getOffsetWidth();

      if (cleft < sleft) {

        c.setScrollLeft(cleft);

      } else if (cright > sright) {

        c.setScrollLeft(cright - scroller.getStyleWidth());

      }

    }

    return cellEl != null ? fly(cellEl).getXY() : new Point(c.getScrollLeft(), fly(rowEl).getY());

  }

  protected Element findHeaderCell(Element elem) {

    Element cell = findCell(elem);

    return cell != null && fly(cell).hasStyleName(hdStyle) ? cell : null;

  }

  protected int findHeaderIndex(Element elem) {

    return findCellIndex(elem, hdStyle);

  }

  protected void fitColumns(boolean preventRefresh, boolean onlyExpand, int omitColumn) {

    int tw = cm.getTotalWidth(false);

    double aw = grid.el().getWidth(true) - scrollOffset;

    if (aw < 0) {

      aw = grid.el().getStyleWidth();

    }

    if (aw < 20 || aw > 2000) { // not initialized, so don't screw up the

      // default widths

      return;

    }

    int extra = (int) aw - tw;

    if (extra == 0) {

      return;

    }

    int vc = cm.getColumnCount(true);

    int ac = vc - (omitColumn != -1 ? 1 : 0);

    if (ac == 0) {

      ac = 1;

      omitColumn = -1;

    }

    int colCount = cm.getColumnCount();

    Stack<Integer> cols = new Stack<Integer>();

    int extraCol = 0;

    int width = 0;

    int w;

    for (int i = 0; i < colCount; i++) {

      if (!cm.isHidden(i) && !cm.isFixed(i) && i != omitColumn) {

        w = cm.getColumnWidth(i);

        cols.push(i);

        extraCol = i;

        cols.push(w);

        width += w;

      }

    }

    double frac = (aw - cm.getTotalWidth()) / width;

    while (cols.size() > 0) {

      w = cols.pop();

      int i = cols.pop();

      int ww = Math.max(grid.getMinColumnWidth(), (int) Math.floor(w + w * frac));

      cm.setColumnWidth(i, ww, true);

    }

    if ((tw = cm.getTotalWidth(false)) > aw) {

      int adjustCol = ac != vc ? omitColumn : extraCol;

      cm.setColumnWidth(adjustCol, (int) Math.max(1, cm.getColumnWidth(adjustCol) - (tw - aw)),

          true);

    }

    if (!preventRefresh) {

      updateAllColumnWidths();

    }

  }

  protected El fly(Element elem) {

    return El.fly(elem);

  }

  protected int getCellIndex(Element elem) {

    if (elem != null) {

      String id = getCellIndexId(elem);

      if (id != null) {

        return cm.getIndexById(id);

      }

    }

    return -1;

  }

  protected List<ColumnData> getColumnData() {

    int colCount = cm.getColumnCount();

    List<ColumnData> cs = new ArrayList<ColumnData>();

    for (int i = 0; i < colCount; i++) {

      String name = cm.getDataIndex(i);

      ColumnData data = new ColumnData();

      data.name = name == null ? cm.getColumnId(i) : name;

      data.renderer = cm.getRenderer(i);

      data.id = cm.getColumnId(i);

      data.style = getColumnStyle(i, false);

      cs.add(data);

    }

    return cs;

  }

  protected Element getEditorParent() {

    return scroller.dom;

  }

  protected String getRenderedValue(ColumnData data, int rowIndex, int colIndex, ModelData m,

      String property) {

    GridCellRenderer r = cm.getRenderer(colIndex);

    if (r != null) {

      return r.render(ds.getAt(rowIndex), property, data, rowIndex, colIndex, ds);

    }

    Object val = m.get(property);

    ColumnConfig c = cm.getColumn(colIndex);

    if (val != null && c.getNumberFormat() != null) {

      Number n = (Number) val;

      NumberFormat nf = cm.getColumn(colIndex).getNumberFormat();

      val = nf.format(n.doubleValue());

    } else if (val != null && c.getDateTimeFormat() != null) {

      DateTimeFormat dtf = c.getDateTimeFormat();

      val = dtf.format((Date) val);

    }

    if (val != null) {

      return val.toString();

    }

    return "";

  }

  protected Element[] getRows() {

    if (!hasRows()) {

      return new Element[0];

    }

    NodeList ns = mainBody.dom.getChildNodes();

    Element[] rows = new Element[ns.getLength()];

    for (int i = 0, len = ns.getLength(); i < len; i++) {

      rows[i] = ns.getItem(i).cast();

    }

    return rows;

  }

  protected native JavaScriptObject getRowsNative(Element body) /*-{

         var fc = body.firstChild;

         if (fc && fc.className == 'x-grid-empty') {

           return [];

         }

         return body.childNodes;

       }-*/;

  protected Point getScrollState() {

    return new Point(scroller.getScrollLeft(), scroller.getScrollTop());

  }

  protected String getTotalWidth() {

    return cm.getTotalWidth() + "px";

  }

  protected void handleComponentEvent(ComponentEvent ce) {

    Element row = findRow(ce.getTarget());

    switch (ce.type) {

      case Event.ONMOUSEOVER:

        if (row != null) onRowOver(row);

        break;

      case Event.ONMOUSEOUT:

        if (overRow != null) onRowOut(overRow);

        break;

      case Event.ONMOUSEDOWN:

        onMouseDown((GridEvent) ce);

        break;

    }

  }

  /**

   * Initializes the view.

   *

   * @param grid the grid

   */

  protected void init(Grid grid) {

    this.grid = grid;

    this.cm = grid.getColumnModel();

    initListeners();

    initTemplates();

    initData(grid.getStore(), cm);

    initUI(grid);

  }

  /**

   * Initializes the data.

   *

   * @param ds the data store

   * @param cm the column model

   */

  protected void initData(ListStore ds, ColumnModel cm) {

    if (this.ds != null) {

      this.ds.removeStoreListener(listener);

    }

    if (ds != null) {

      ds.addStoreListener(listener);

    }

    this.ds = ds;

    if (this.cm != null) {

      this.cm.removeListener(Events.HiddenChange, columnListener);

      this.cm.removeListener(Events.HeaderChange, columnListener);

      this.cm.removeListener(Events.WidthChange, columnListener);

    }

    if (cm != null) {

      cm.addListener(Events.HiddenChange, columnListener);

      cm.addListener(Events.HeaderChange, columnListener);

      cm.addListener(Events.WidthChange, columnListener);

    }

    this.cm = cm;

  }

  protected void initElements() {

    NodeList cs = grid.getElement().getFirstChild().getChildNodes();

    el = grid.el().firstChild();

    mainWrap = new El((com.google.gwt.user.client.Element) cs.getItem(0));

    mainHd = mainWrap.firstChild();

    if (grid.isHideHeaders()) {

      mainHd.setVisible(false);

    }

    innerHd = mainHd.firstChild();

    scroller = mainWrap.getChild(1);

    scroller.addEventsSunk(Event.ONSCROLL);

    if (forceFit) {

      scroller.setStyleAttribute("overflowX", "hidden");

    }

    mainBody = scroller.firstChild();

    focusEl = scroller.getChild(1);

  }

  protected void initListeners() {

    listener = new StoreListener() {

      @Override

      public void storeAdd(StoreEvent se) {

        onAdd(ds, se.models, se.index);

      }

      @Override

      public void storeBeforeDataChanged(StoreEvent se) {

        onBeforeDataChanged(se);

      }

      @Override

      public void storeClear(StoreEvent se) {

        onClear(se);

      }

      @Override

      public void storeDataChanged(StoreEvent se) {

        onDataChanged(se);

      }

      @Override

      public void storeFilter(StoreEvent se) {

        onDataChanged(se);

      }

      @Override

      public void storeRemove(StoreEvent se) {

        onRemove(ds, se.model, se.index, false);

      }

      @Override

      public void storeUpdate(StoreEvent se) {

        onUpdate(ds, se.model);

      }

    };

    headerListener = new EventListener() {

      public void onBrowserEvent(Event event) {

        switch (DOM.eventGetType(event)) {

          case Event.ONMOUSEOVER:

            handleHdOver(event);

            break;

          case Event.ONMOUSEOUT:

            handleHdOut(event);

            break;

          case Event.ONMOUSEMOVE:

            handleHdMove(event);

            break;

          case Event.ONCLICK:

            handleHdDown(event);

            break;

        }

      }

    };

    scrollListener = new EventListener() {

      public void onBrowserEvent(Event event) {

        if (event.getTypeInt() == Event.ONSCROLL) {

          syncScroll();

        }

      }

    };

    columnListener = new Listener<ColumnModelEvent>() {

      public void handleEvent(ColumnModelEvent be) {

        switch (be.type) {

          case Events.HiddenChange:

            onHiddenChange(cm, be.colIndex, be.hidden);

            break;

          case Events.HeaderChange:

            onHeaderChange();

            break;

          case Events.WidthChange:

            onColumnWidthChange(be.colIndex, be.width);

            break;

        }

      }

    };

  }

  protected void initTemplates() {

    templates = GWT.create(GridTemplates.class);

  }

  protected void initUI(final Grid grid) {

    grid.addListener(Events.HeaderClick, new Listener<GridEvent>() {

      public void handleEvent(GridEvent e) {

        if (!e.getTargetEl().is(".x-grid3-hd-btn")) {

          onHeaderClick(grid, e.colIndex);

        }

      }

    });

  }

  protected void insertRows(ListStore store, int firstRow, int lastRow, boolean isUpdate) {