// update size/position of all child grids and of this grid within this parent.
// this is called when the grid scrolls, when it's size changes, and when
// rows or columns are added, removed, or resized.
private void UpdateChildren()
{
try
{
// update position of all children
for (int row = 0; row < Rows.Count; row++)
{
C1FlexDataTree child = Rows[row].UserData as C1FlexDataTree;
if (child != null)
{
child.UpdatePosition();
}
}
}
catch
{
}
// and update position of this grid within its parent
UpdatePosition();
}
// expand/collapse child grid
//
// if the user clicks the icons (drawn in the method above), either
// create a child grid (and bind it to the detail records), or remove
// the existing one.
//
override protected void OnBeforeMouseDown(BeforeMouseDownEventArgs e)
{
// always call base implementation
base.OnBeforeMouseDown(e);
// check that it's the Left button and that we have a hierarchy
if (e.Button != MouseButtons.Left || _colChild == null)
{
return;
}
// check that it's a row header cell
HitTestInfo hit = HitTest(e.X, e.Y);
if (hit.Type != HitTestTypeEnum.RowHeader || hit.Row < Rows.Fixed)
{
return;
}
// check that the click was over the collapse/expand icon
if (e.X < Cols[0].Right - (Glyphs[GlyphEnum.Collapsed].Width + 4) || _colChild[hit.Row] == null)
{
return;
}
// all checks OK, cancel click before proceeding
e.Cancel = true;
Select(hit.Row, Cols.Fixed, hit.Row, Cols.Count - 1, false);
// create and show child grid
if (Rows[hit.Row].UserData == null)
{
// create child grid
C1FlexDataTree childGrid = new C1FlexDataTree();
childGrid.Visible = false;
childGrid.ScrollBars = ScrollBars.Horizontal;
// attach child grid to parent, set data source
Controls.Add(childGrid);
childGrid.ApplyParentStyles(this);
childGrid.DataSource = _colChild[hit.Row];
// save references:
// child grid Tag property contains a reference to the parent row
// parent row UserData contains a reference to the child grid
childGrid.Tag = Rows[hit.Row];
Rows[hit.Row].UserData = childGrid;
// add node row (unbound) to display child
Rows.InsertNode(hit.Row + 1, -1);
// move child grid into position, make it visible
childGrid.UpdatePosition();
childGrid.Visible = true;
childGrid.Focus();
}
else // hide and delete child grid
{
// get child grid
C1FlexDataTree childGrid = (C1FlexDataTree)Rows[hit.Row].UserData;
// break references
Rows[hit.Row].UserData = null;
childGrid.Tag = null;
// clear child and remove it from parent
childGrid.Controls.Clear();
Controls.Remove(childGrid);
// delete container row
var removeRowIndex = hit.Row + 1;
if (Rows.Count > removeRowIndex)
{
Rows.Remove(removeRowIndex);
}
}
}
