void EnsureView(object source, Type collectionViewType)
{
if (_isInitializing || _deferLevel > 0)
{
return;
}
DataSourceProvider dataProvider = source as DataSourceProvider;
// listen for DataChanged events from an DataSourceProvider
if (dataProvider != _dataProvider)
{
if (_dataProvider != null)
{
DataChangedEventManager.RemoveHandler(_dataProvider, OnDataChanged);
}
_dataProvider = dataProvider;
if (_dataProvider != null)
{
DataChangedEventManager.AddHandler(_dataProvider, OnDataChanged);
_dataProvider.InitialLoad();
}
}
// if the source is DataSourceProvider, use its Data instead
if (dataProvider != null)
{
source = dataProvider.Data;
}
// get the view
ICollectionView view = null;
if (source != null)
{
DataBindEngine engine = DataBindEngine.CurrentDataBindEngine;
ViewRecord viewRecord = engine.GetViewRecord(source, this, collectionViewType, true,
(object x) =>
{
BindingExpressionBase beb = BindingOperations.GetBindingExpressionBase(this, SourceProperty);
return((beb != null) ? beb.GetSourceItem(x) : null);
});
if (viewRecord != null)
{
view = viewRecord.View;
_isViewInitialized = viewRecord.IsInitialized;
// bring view up to date with the CollectionViewSource
if (_version != viewRecord.Version)
{
ApplyPropertiesToView(view);
viewRecord.Version = _version;
}
}
}
// update the View property
SetValue(ViewPropertyKey, view);
}