I am trying to lock a slot in my inventory to a specific item, so i can oly inert THAT item in THAT slot and no other.

 

i tried it with "isItemValidForSlot" but i couldnt get it to work that way.

thats how i tried it:

@Override
public boolean isItemValidForSlot(int slot, ItemStack item) {
if(slot == 0 && item.getItem() == ModItems.toolOsniumKnife) return true;
return false;
}

package com.wizcraft.gui;

import com.wizcraft.tile.entity.TileEntityTableWittle;

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

public class ContainerTableWittle extends Container {

protected TileEntityTableWittle tile;

public ContainerTableWittle(InventoryPlayer invPlayer, TileEntityTableWittle tile){
	this.tile = tile;
	this.addSlotToContainer(new Slot(tile, 0, 52, 7));
	this.addSlotToContainer(new Slot(tile, 1, 52, 34));
	this.addSlotToContainer(new Slot(tile, 2, 52, 61));
	this.addSlotToContainer(new Slot(tile, 3, 25, 34));
	this.addSlotToContainer(new Slot(tile, 4, 79, 34));
	this.addSlotToContainer(new Slot(tile, 5, 131, 34));

	bindPlayerInventory(invPlayer);
}

@Override
    public boolean canInteractWith(EntityPlayer player) {
            return tile.isUseableByPlayer(player);
    }


    protected void bindPlayerInventory(InventoryPlayer invPlayer) {
    	for(int i = 0; i<3;i++){
		for(int j = 0; j<9;j++){
			this.addSlotToContainer(new Slot(invPlayer, 9+j+i*9, 8 + j*18, 84+i*18));
		}
	}

	for(int i = 0; i<9;i++){
		this.addSlotToContainer(new Slot(invPlayer, i, 8 + i*18, 142));
	}
    }

    @Override
    public ItemStack transferStackInSlot(EntityPlayer player, int slot) {
            ItemStack stack = null;
            Slot slotObject = (Slot) inventorySlots.get(slot);

            //null checks and checks if the item can be stacked (maxStackSize > 1)
            if (slotObject != null && slotObject.getHasStack()) {
                    ItemStack stackInSlot = slotObject.getStack();
                    stack = stackInSlot.copy();

                    //merges the item into player inventory since its in the tile
                    if (slot < tile.getSizeInventory()) {
                            if (!this.mergeItemStack(stackInSlot, tile.getSizeInventory(), 36+tile.getSizeInventory(), true)) {
                                    return null;
                            }
                    }
                    //places it into the tile is possible since its in the player inventory
                    else if (!this.mergeItemStack(stackInSlot, 0, tile.getSizeInventory(), false)) {
                            return null;
                    }

                    if (stackInSlot.stackSize == 0) {
                            slotObject.putStack(null);
                    } else {
                            slotObject.onSlotChanged();
                    }

                    if (stackInSlot.stackSize == stack.stackSize) {
                            return null;
                    }
                    slotObject.onPickupFromSlot(player, stackInSlot);
            }
            return stack;
    }
}

I created a custom slot class and set the "isitemValid" to similar to what was in the method from the tileentity and now it works.

PS:

i never made a more complex gui than a chest before.

THANK YOU