protected override void CommitProperties()
{
IndexChangeEvent e;
bool changedSelection = false;
base.CommitProperties();
if (_dataProviderChanged)
{
_dataProviderChanged = false;
DoingWholesaleChanges = false;
if (_selectedIndex >= 0 && null != DataProvider && _selectedIndex < DataProvider.Length)
ItemSelected(_selectedIndex, true);
else if (_requireSelection)
ProposedSelectedIndex = 0;
else
SetSelectedIndex(-1, false);
}
if (_requireSelectionChanged)
{
_requireSelectionChanged = false;
if (_requireSelection &&
SelectedIndex == NO_SELECTION &&
null != DataProvider &&
DataProvider.Length > 0)
{
// Set the proposed selected index here to make sure
// CommitSelection() is called below.
ProposedSelectedIndex = 0;
}
}
if (null != PendingSelectedItem)
{
if (null != DataProvider)
ProposedSelectedIndex = DataProvider.GetItemIndex(PendingSelectedItem);
if (AllowCustomSelectedItem && ProposedSelectedIndex == -1)
{
ProposedSelectedIndex = CUSTOM_SELECTED_ITEM;
_selectedItem = PendingSelectedItem;
}
PendingSelectedItem = null;
}
if (ProposedSelectedIndex != NO_PROPOSED_SELECTION)
changedSelection = CommitSelection(true);
// If the selectedIndex has been adjusted to account for items that
// have been added or removed, send out a "change" event
// so any bindings to selectedIndex are updated correctly.
if (SelectedIndexAdjusted)
{
SelectedIndexAdjusted = false;
if (!changedSelection)
{
DispatchEvent(new FrameworkEvent(FrameworkEvent.VALUE_COMMIT));
}
}
if (CaretIndexAdjusted)
{
CaretIndexAdjusted = false;
if (!changedSelection)
{
// Put the new caretIndex renderer into the
// caret state and dispatch an "caretChange"
// event to update any bindings. Additionally, update
// the backing variable.
ItemShowingCaret(_selectedIndex, true);
_caretIndex = _selectedIndex;
e = new IndexChangeEvent(IndexChangeEvent.CARET_CHANGE);
e.OldIndex = _caretIndex;
e.NewIndex = _caretIndex;
DispatchEvent(e);
}
}
if (_labelFieldOrFunctionChanged)
{
_labelFieldOrFunctionChanged = false;
// Cycle through all instantiated renderers to push the correct text
// in to the renderer by setting its label property
if (null != DataGroup)
{
// if virtual layout, only loop through the indices in view
// otherwise, loop through all of the item renderers
/*if (null != Layout && Layout.UseVirtualLayout)
{
foreach (int itemIndex in DataGroup.GetItemIndicesInView())
{
UpdateRendererLabelProperty(itemIndex);
}
}
else
{*/
var n = DataGroup.NumberOfContentChildren;
for (var itemIndex = 0; itemIndex < n; itemIndex++)
{
UpdateRendererLabelProperty(itemIndex);
}
/*}*/
}
}
}
/**
*
* The selection validation and commitment workhorse method.
* Called to commit the pending selected index. This method dispatches
* the "changing" event, and if the event is not cancelled,
* commits the selection change and then dispatches the "change"
* event.
*
* Returns true if the selection was committed, or false if the selection
* was cancelled.
*/
protected virtual bool CommitSelection(bool dispatchChangedEvents/* = true*/)
{
// Step 1: make sure the proposed selected index is in range.
var maxIndex = null != DataProvider ? DataProvider.Length - 1 : -1;
var oldSelectedIndex = _selectedIndex;
var oldCaretIndex = _caretIndex;
IndexChangeEvent e;
if (!AllowCustomSelectedItem || ProposedSelectedIndex != CUSTOM_SELECTED_ITEM)
{
if (ProposedSelectedIndex < NO_SELECTION)
ProposedSelectedIndex = NO_SELECTION;
if (ProposedSelectedIndex > maxIndex)
ProposedSelectedIndex = maxIndex;
if (_requireSelection && ProposedSelectedIndex == NO_SELECTION &&
null != DataProvider && DataProvider.Length > 0)
{
ProposedSelectedIndex = NO_PROPOSED_SELECTION;
return false;
}
}
// Step 2: dispatch the "changing" event. If preventDefault() is called
// on this event, the selection change will be cancelled.
if (DispatchChangeAfterSelection)
{
e = new IndexChangeEvent(IndexChangeEvent.CHANGING, false, true)
{
OldIndex = _selectedIndex,
NewIndex = ProposedSelectedIndex
};
//if (!DispatchEvent(e))
if (e.DefaultPrevented)
{
// The event was cancelled. Cancel the selection change and return.
ProposedSelectedIndex = NO_PROPOSED_SELECTION;
return false;
}
}
// Step 3: commit the selection change and caret change
_selectedIndex = ProposedSelectedIndex;
ProposedSelectedIndex = NO_PROPOSED_SELECTION;
if (oldSelectedIndex != NO_SELECTION)
ItemSelected(oldSelectedIndex, false);
if (_selectedIndex != NO_SELECTION && _selectedIndex != CUSTOM_SELECTED_ITEM)
ItemSelected(_selectedIndex, true);
SetCurrentCaretIndex(_selectedIndex);
// Step 4: dispatch the "change" event and "caretChange"
// events based on the dispatchChangeEvents parameter. Overrides may
// chose to dispatch the change/caretChange events
// themselves, in which case we wouldn't want to dispatch the event
// here.
if (dispatchChangedEvents)
{
// Dispatch the change event
if (DispatchChangeAfterSelection)
{
e = new IndexChangeEvent(IndexChangeEvent.CHANGE)
{
OldIndex = oldSelectedIndex,
NewIndex = _selectedIndex
};
DispatchEvent(e);
DispatchChangeAfterSelection = false;
}
else
{
DispatchEvent(new FrameworkEvent(FrameworkEvent.VALUE_COMMIT));
}
//Dispatch the caretChange event
e = new IndexChangeEvent(IndexChangeEvent.CARET_CHANGE)
{
OldIndex = oldCaretIndex,
NewIndex = _caretIndex
};
DispatchEvent(e);
}
return true;
}
/**
*
*/
private void DispatchChangeEvent(int oldIndex, int newIndex)
{
var e = new IndexChangeEvent(Event.CHANGE)
{
OldIndex = oldIndex,
NewIndex = newIndex,
RelatedObject = GetChildAt(newIndex)
};
DispatchEvent(e);
}