public void handleRequestAnswer(Collection<ItemIdentifierStack> items, boolean error, ISubGuiControler control, EntityPlayer player) {
while(control.hasSubGui()) {
control = control.getSubGui();
}
if (error) {
control.setSubGui(new GuiRequestPopup(_entityPlayer, "You are missing:", items));
} else {
control.setSubGui(new GuiRequestPopup(_entityPlayer, "Request successful!", items));
}
}