ComboBoxString crash in HandleSelectionChanged

Development Programming & Scripting UI
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1

This method will crash if the user of the control has deleted it in response to OnSelectionChanged event, e.g. when selecting a ComboBox option closes a dialog. This effectively invalidates the shared pointer to ComboBoxContent.

void UComboBoxString::HandleSelectionChanged(TSharedPtr<FString> Item, ESelectInfo::Type SelectionType)
{
	CurrentOptionPtr = Item;
	SelectedOption = CurrentOptionPtr.IsValid() ? CurrentOptionPtr.ToSharedRef().Get() : FString();

	if ( !IsDesignTime() )
	{
		OnSelectionChanged.Broadcast(Item.IsValid() ? *Item : FString(), SelectionType);
	}

	// When the selection changes we always generate another widget to represent the content area of the comobox.
	ComoboBoxContent->SetContent( HandleGenerateWidget(CurrentOptionPtr) );
}

Last line should be changed to:

if (ComboBoxContent.IsValid())
{
    ComoboBoxContent->SetContent( HandleGenerateWidget(CurrentOptionPtr) );
}