GhostSlot.java

package gr8pefish.ironbackpacks.container.slot;

import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.inventory.IInventory;
import net.minecraft.inventory.Slot;
import net.minecraft.item.ItemStack;

/**
 * Used in the alternate gui to create a 'ghost items' that disappears when it is picked up and doesn't decrement the items stack when it is placed in.
 */
public class GhostSlot extends BackpackSlot {

    public int index; //the slot index in the inventory

    public GhostSlot(IInventory iInventory, int index, int x, int y) {
        super(iInventory, index, x, y);
        this.index = index;
    }

    @Override
    public boolean canTakeStack(EntityPlayer player){
        return false; //disallow things to take the slot (such as double click causing item duping)
    }

    @Override
    public ItemStack decrStackSize(int par1){
        return null;
    }

    //Always sets the stack size to 1
    @Override
    public void putStack(ItemStack itemStack){
        if(itemStack != null) {
            itemStack.stackSize = 1;
            inventory.setInventorySlotContents(index, itemStack.copy());
        } else {
            inventory.setInventorySlotContents(index, null);
        }
        onSlotChanged();
    }

}