How to use

getViewer

method

in

org.eclipse.jface.viewers.TreeViewerFocusCellManager

  @Override
  public ViewerCell getFocusCell() {
    ViewerCell cell = super.getFocusCell();
    Tree t = (Tree) getViewer().getControl();

    // It is possible that the selection has changed under the hood
    if (cell != null) {
      if (t.getSelection().length == 1
          && t.getSelection()[0] != cell.getItem()) {
        setFocusCell(getViewer().getViewerRowFromItem(
            t.getSelection()[0]).getCell(cell.getColumnIndex()));
      }
    }

    return super.getFocusCell();
  }
}

  @Override
  public ViewerCell getFocusCell() {
    ViewerCell cell = super.getFocusCell();
    Tree t = (Tree) getViewer().getControl();

    // It is possible that the selection has changed under the hood
    if (cell != null) {
      if (t.getSelection().length == 1
          && t.getSelection()[0] != cell.getItem()) {
        setFocusCell(getViewer().getViewerRowFromItem(
            t.getSelection()[0]).getCell(cell.getColumnIndex()));
      }
    }

    return super.getFocusCell();
  }
}

@Override
ViewerCell getInitialFocusCell() {
  Tree tree = (Tree) getViewer().getControl();
  if (! tree.isDisposed() && tree.getItemCount() > 0 && ! tree.getTopItem().isDisposed()) {
    ViewerRow aViewerRow = getViewer().getViewerRowFromItem(tree.getTopItem());
    if (tree.getColumnCount() == 0) {
      return aViewerRow.getCell(0);
    }
    Rectangle clientArea = tree.getClientArea();
    for (int i = 0; i < tree.getColumnCount(); i++) {
      if (aViewerRow.getWidth(i) > 0 && columnInVisibleArea(clientArea,aViewerRow,i))
        return aViewerRow.getCell(i);
    }
  }
  return null;
}

@Override
ViewerCell getInitialFocusCell() {
  Tree tree = (Tree) getViewer().getControl();
  if (! tree.isDisposed() && tree.getItemCount() > 0 && ! tree.getTopItem().isDisposed()) {
    ViewerRow aViewerRow = getViewer().getViewerRowFromItem(tree.getTopItem());
    if (tree.getColumnCount() == 0) {
      return aViewerRow.getCell(0);
    }
    Rectangle clientArea = tree.getClientArea();
    for (int i = 0; i < tree.getColumnCount(); i++) {
      if (aViewerRow.getWidth(i) > 0 && columnInVisibleArea(clientArea,aViewerRow,i))
        return aViewerRow.getCell(i);
    }
  }
  return null;
}