/// <summary>
/// Switch the selection column. For multiselect, the behavior is highly dependent on the
/// the ColumnSelectionTransferAction property and the prior state of the permutation, if
/// the permutation is being reordered
/// </summary>
/// <param name="column">The new selection column</param>
/// <param name="oldPermutation">The old column permuation</param>
/// <param name="fireEvents">True if this routine should fire selection events</param>
private void SetSelectionColumn(int column, ColumnPermutation oldPermutation, bool fireEvents)
{
Debug.Assert(oldPermutation != null || column != mySelectionColumn);
var iCaret = CurrentIndex;
DismissLabelEdit(false, false);
var oldColumn = mySelectionColumn;
mySelectionColumn = column;
if (GetStyleFlag(VTCStyleFlags.MultiSelect))
{
switch (myColumnSelectionAction)
{
case ColumnSelectionTransferAction.PreserveNonBlankCells:
SetSelectionColumn_PreserveBasic(oldColumn, oldPermutation, column, false, fireEvents);
break;
case ColumnSelectionTransferAction.PreserveAnchoredCells:
SetSelectionColumn_PreserveBasic(oldColumn, oldPermutation, column, true, fireEvents);
break;
case ColumnSelectionTransferAction.PreserveSharedAnchors:
SetSelectionColumn_PreserveAnchors(oldColumn, oldPermutation, column, false, fireEvents);
break;
case ColumnSelectionTransferAction.PreserveSharedAnchorsOnly:
SetSelectionColumn_PreserveAnchors(oldColumn, oldPermutation, column, true, fireEvents);
break;
case ColumnSelectionTransferAction.ClearSelectedRows:
SetSelectionColumn_Clear(fireEvents);
break;
}
}
else if (iCaret != -1 && fireEvents)
{
CurrentIndex = iCaret;
}
if (oldColumn != mySelectionColumn)
{
// This may cause a focus change, because the caret moves to a different column.
if (!GetStateFlag(VTCStateFlags.RestoringSelection) &&
VirtualTreeAccEvents.ShouldNotify(VirtualTreeAccEvents.eventObjectFocus, this) &&
Focused)
{
VirtualTreeAccEvents.Notify(
VirtualTreeAccEvents.eventObjectFocus, CurrentIndex,
CurrentColumn, this);
}
// ensure newly selected column is scrolled into view.
if (HasHorizontalScrollBar)
{
ScrollColumnIntoView(CurrentColumn);
}
// make sure we invalidate the caret item
if (CurrentIndex != VirtualTreeConstant.NullIndex)
{
InvalidateItem(CurrentIndex, -1, NativeMethods.RedrawWindowFlags.Invalidate);
}
}
}
/// <summary>
/// Fires WinEvents for given selection change.
/// </summary>
private void FireWinEventsForSelection(bool extendFromAnchor, bool preserveSelection, ModifySelectionAction caretAction)
{
if (GetStateFlag(VTCStateFlags.RestoringSelection))
{
return; // no events if we're restoring selection.
}
if (SelectionCount == 1)
{
// if there's currently only one thing selected, we know we should fire a regular selection event.
if (VirtualTreeAccEvents.ShouldNotify(VirtualTreeAccEvents.eventObjectSelection, this))
{
VirtualTreeAccEvents.Notify(
VirtualTreeAccEvents.eventObjectSelection, CurrentIndex,
CurrentColumn, this);
}
}
else if (extendFromAnchor)
{
if (VirtualTreeAccEvents.ShouldNotify(VirtualTreeAccEvents.eventObjectSelectionWithin, this))
{
// we extended selection from the anchor position, this constitutes a significant change in selection
// state, so we fire selection within from the tree control, and let clients query us for the result.
// UNDONE: querying currently won't work because we need a way to return an IEnumVariant from IAccessible::get_accSelection.
// We just fire selection for the caret instead.
// VirtualTreeAccEvents.Notify(VirtualTreeAccEvents.eventObjectSelectionWithin, VirtualTreeConstant.NullIndex,
// VirtualTreeConstant.NullIndex, this);
VirtualTreeAccEvents.Notify(
VirtualTreeAccEvents.eventObjectSelection, CurrentIndex,
CurrentColumn, this);
}
}
else if (preserveSelection)
{
// we're preserving an original selection, which means that we fire either an add or a remove,
// depending on what happened to the caret
switch (caretAction)
{
case ModifySelectionAction.Select:
if (VirtualTreeAccEvents.ShouldNotify(VirtualTreeAccEvents.eventObjectSelectionAdd, this))
{
VirtualTreeAccEvents.Notify(
VirtualTreeAccEvents.eventObjectSelectionAdd, CurrentIndex,
CurrentColumn, this);
}
break;
case ModifySelectionAction.Clear:
if (VirtualTreeAccEvents.ShouldNotify(VirtualTreeAccEvents.eventObjectSelectionRemove, this))
{
VirtualTreeAccEvents.Notify(
VirtualTreeAccEvents.eventObjectSelectionRemove, CurrentIndex,
CurrentColumn, this);
}
break;
case ModifySelectionAction.Toggle:
if (IsSelected(CaretIndex))
{
goto case ModifySelectionAction.Select;
}
else
{
goto case ModifySelectionAction.Clear;
}
case ModifySelectionAction.None:
// Caret position didn't change, but selection still changed overall. This happens, for instance,
// during cross-column selection transfer. We would ideally fire selection within here, for now
// we just fire selection at the caret position anyway.
if (VirtualTreeAccEvents.ShouldNotify(VirtualTreeAccEvents.eventObjectSelectionWithin, this))
{
//VirtualTreeAccEvents.Notify(VirtualTreeAccEvents.eventObjectSelectionWithin, VirtualTreeConstant.NullIndex,
// VirtualTreeConstant.NullIndex, this);
VirtualTreeAccEvents.Notify(
VirtualTreeAccEvents.eventObjectSelection, CurrentIndex,
CurrentColumn, this);
}
break;
}
}
}