Fix ItemFrameListener with Item in ItemFrame

BauSystem_Main/src/de/steamwar/bausystem/world/ItemFrameListener.java

@@ -20,11 +20,13 @@
 package de.steamwar.bausystem.world;
 
 import de.steamwar.bausystem.SWUtils;
+import org.bukkit.Material;
 import org.bukkit.entity.ItemFrame;
 import org.bukkit.entity.Player;
 import org.bukkit.event.EventHandler;
 import org.bukkit.event.Listener;
 import org.bukkit.event.entity.EntityDamageByEntityEvent;
+import org.bukkit.inventory.ItemStack;
 
 public class ItemFrameListener implements Listener {
 
@@ -38,8 +40,13 @@ public class ItemFrameListener implements Listener {
         }
         event.setCancelled(true);
         ItemFrame itemFrame = (ItemFrame) event.getEntity();
-        SWUtils.giveItemToPlayer((Player) event.getDamager(), itemFrame.getItem());
-        itemFrame.remove();
+        ItemStack itemStack = itemFrame.getItem();
+        if (itemStack.getType() != Material.AIR) {
+            SWUtils.giveItemToPlayer((Player) event.getDamager(), itemFrame.getItem());
+            itemFrame.setItem(null);
+        } else {
+            itemFrame.remove();
+        }
     }
 
 }