private void aCheckBoxUIElement_ElementClick(Object sender, Infragistics.Win.UIElementEventArgs e)
{
// Get the CheckBoxUIElement that was clicked
CheckBoxUIElement aCheckBoxUIElement = (CheckBoxUIElement)e.Element;
// Get the Header associated with this particular element
Infragistics.Win.UltraWinGrid.ColumnHeader aColumnHeader = (Infragistics.Win.UltraWinGrid.ColumnHeader)aCheckBoxUIElement.GetAncestor(typeof(HeaderUIElement)).GetContext(typeof(Infragistics.Win.UltraWinGrid.ColumnHeader));
// Set the Tag on the Header to the new CheckState
aColumnHeader.Tag = aCheckBoxUIElement.CheckState;
// So that we can apply various changes only to the relevant Rows collection that the header belongs to
HeaderUIElement aHeaderUIElement = aCheckBoxUIElement.GetAncestor(typeof(HeaderUIElement)) as HeaderUIElement;
RowsCollection hRows = aHeaderUIElement.GetContext(typeof(RowsCollection)) as RowsCollection;
// Raise an event so the programmer can do something when the CheckState changes
if (_CLICKED != null)
{
_CLICKED(this, new HeaderCheckBoxEventArgs(aColumnHeader, aCheckBoxUIElement.CheckState, hRows));
}
}
public void AfterCreateChildElements(Infragistics.Win.UIElement parent) // Implements Infragistics.Win.IUIElementCreationFilter.AfterCreateChildElements
{
// Check for the HeaderUIElement
if (parent is HeaderUIElement)
{
// Get the HeaderBase object from the HeaderUIElement
Infragistics.Win.UltraWinGrid.HeaderBase aHeader = ((HeaderUIElement)parent).Header;
// Only put the checkbox into headers whose DataType is boolean
if (aHeader.Column.DataType == typeof(bool))
{
TextUIElement aTextUIElement;
CheckBoxUIElement aCheckBoxUIElement = (CheckBoxUIElement)parent.GetDescendant(typeof(CheckBoxUIElement));
// Since the grid sometimes re-uses UIElements, we need to check to make sure
// the header does not already have a CheckBoxUIElement attached to it.
// If it does, we just get a reference to the existing CheckBoxUIElement,
// and reset its properties.
if (aCheckBoxUIElement == null)
{
//Create a New CheckBoxUIElement
aCheckBoxUIElement = new CheckBoxUIElement(parent);
}
// Get the TextUIElement - this is where the text for the
// Header is displayed. We need this so we can push it to the right
// in order to make room for the CheckBox
aTextUIElement = (TextUIElement)parent.GetDescendant(typeof(TextUIElement));
// Sanity check
if (aTextUIElement == null)
{
return;
}
// Get the Header and see if the Tag has been set. If the Tag is
// set, we will assume it's the stored CheckState. This has to be
// done in order to maintain the CheckState when the grid repaints and
// UIElement are destroyed and recreated.
Infragistics.Win.UltraWinGrid.ColumnHeader aColumnHeader =
(Infragistics.Win.UltraWinGrid.ColumnHeader)aCheckBoxUIElement.GetAncestor(typeof(HeaderUIElement))
.GetContext(typeof(Infragistics.Win.UltraWinGrid.ColumnHeader));
if (aColumnHeader.Tag == null)
{
//If the tag was nothing, this is probably the first time this
//Header is being displayed, so default to Indeterminate
aColumnHeader.Tag = CheckState.Indeterminate;
}
else
{
aCheckBoxUIElement.CheckState = (CheckState)aColumnHeader.Tag;
}
// Hook the ElementClick of the CheckBoxUIElement
aCheckBoxUIElement.ElementClick += new UIElementEventHandler(aCheckBoxUIElement_ElementClick);
// Add the CheckBoxUIElement to the HeaderUIElement
parent.ChildElements.Add(aCheckBoxUIElement);
// Position the CheckBoxUIElement. The number 3 here is used for 3
// pixels of padding between the CheckBox and the edge of the Header.
// The CheckBox is shifted down slightly so it is centered in the header.
aCheckBoxUIElement.Rect = new Rectangle(parent.Rect.X + 3, parent.Rect.Y + ((parent.Rect.Height - aCheckBoxUIElement.CheckSize.Height) / 2), aCheckBoxUIElement.CheckSize.Width, aCheckBoxUIElement.CheckSize.Height);
// Push the TextUIElement to the right a little to make
// room for the CheckBox. 3 pixels of padding are used again.
aTextUIElement.Rect = new Rectangle(aCheckBoxUIElement.Rect.Right + 3, aTextUIElement.Rect.Y, parent.Rect.Width - (aCheckBoxUIElement.Rect.Right - parent.Rect.X), aTextUIElement.Rect.Height);
}
else
{
// If the column is not a boolean column, we do not want to have a checkbox in it
// Since UIElements can be reused by the grid, there is a chance that one of the
// HeaderUIElements that we added a checkbox to for a boolean column header
// will be reused in a column that is not boolean. In this case, we must remove
// the checkbox so that it will not appear in an inappropriate column header.
CheckBoxUIElement aCheckBoxUIElement = (CheckBoxUIElement)parent.GetDescendant(typeof(CheckBoxUIElement));
if (aCheckBoxUIElement != null)
{
parent.ChildElements.Remove(aCheckBoxUIElement);
aCheckBoxUIElement.Dispose();
}
}
}
}
