SetResourceObject LNK1120 error

I’m trying to change button image in runtime using SetResourceObject(). But LNK1120 error occurs.
I tried including “Runtime/SlateCore/Public/SlateCore.h”. It changes nothing.
I don’t know what to do.

void UFP_InventoryWidget::ViewAllSortByTier()
{
	TMap<int, AFP_Rune*> SortByTier;

	for (int i = 0; i < Inventory.Num(); ++i)
		SortByTier.Add(Inventory[i]->Stat.Tier, Inventory[i]);

	TMap<int, AFP_Rune*>::TIterator iter = SortByTier.CreateIterator();

	for (int i = 0; iter.Value() != NULL; ++iter, ++i)
	{
		Slots[i]->WidgetStyle.Normal.SetResourceObject(iter.Value()->Icon);
	}
}

Icon is UTexture2D*.

Hi,
Go to your project root folder then Source/YourProjectName/ open YourProjectName.Build.cs and uncomment / add this

PrivateDependencyModuleNames.AddRange(new string[] { "Slate", "SlateCore" });

It worked!! Thanks.