Container problems...

gistfile1.java

package com.kwibble.dendri.inventory.dendrikbelt;

import com.kwibble.dendri.entity.player.PlayerInformation;
import com.kwibble.dendri.inventory.SlotDendrikBelt;
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;

/**
 * Created by Kwibble on 2/07/14.
 */
public class ContainerTabMain extends Container
{
	private static final int INV_START = 5, INV_END = INV_START+26,
			HOTBAR_START = INV_END+1, HOTBAR_END = HOTBAR_START+8;

	public ContainerTabMain(EntityPlayer player, final InventoryPlayer playerInventory)
	{
		PlayerInformation playerinfo = PlayerInformation.forPlayer(player);

		playerinfo.setInventoryDendrikBelt(new InventoryDendrikBelt(player));
		InventoryDendrikBelt beltInventory = playerinfo.getInventoryDendrikBelt();

		int i, j;

		this.addSlotToContainer(new SlotDendrikBelt(beltInventory, 0, 62, 8)).putStack(new ItemStack(playerinfo.getCurrentDendrikBelt()));

		for (i = 0; i < beltInventory.INV_SIZE; ++i)
		{
			int x = 27;
			int y = 0;
			if (i > 0)
			{
				x = 28;
				y = 1;
			}
			this.addSlotToContainer(new SlotMistBottle(beltInventory, 1 + i, 68 + (i * x) - y, 45));
		}

		for (i = 0; i < 3; ++i)
		{
			for (j = 0; j < 9; ++j)
			{
				this.addSlotToContainer(new Slot(playerInventory, (j + (i + 1) * 9), 8 + j * 18, 84 + i * 18));
			}
		}

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

	@Override
	public boolean canInteractWith(EntityPlayer var1)
	{
		return true;
	}

	@Override
	public ItemStack transferStackInSlot(EntityPlayer par1EntityPlayer, int slot_position)
	{
		// Setup Variables
		ItemStack stack_return = null;
		// Get Current Slot
		Slot slot = (Slot)this.inventorySlots.get(slot_position);
		// Check to see if slot exists and if it has an item
		if (slot != null && slot.getHasStack())
		{
			// Get Current itemstack
			ItemStack stack_active = slot.getStack();
			// Put is stack memory
			stack_return = stack_active.copy();
//			if (stack_return.getItem() instanceof ItemDendrikBelt && !( (Slot) this.inventorySlots.get(0) ).getHasStack())
//			{
//				// Check for spot
//				if (!this.mergeItemStack(stack_active, 0, 1, false))
//				{
//					return null;
//				}
////				// Test for mist bottles
//			} else if (stack_return.getItem() instanceof ItemMistBottle && slot_position >= 1 && slot_position < INV_START) {
//				// Check for spot
//				if (!this.mergeItemStack(stack_active, 1, 5, false))
//				{
//					return null;
//				}
//				// Test for main inventory
		    if (slot_position >= INV_START && slot_position < INV_END + 1) {

				if (!this.mergeItemStack(stack_active, HOTBAR_START, HOTBAR_END, false)) {
					return null;
				}
				// Test for main bar
			}
			else if (slot_position >= HOTBAR_START && slot_position < HOTBAR_END + 1) {
				if (!this.mergeItemStack(stack_active, INV_START, INV_END, false)) {
					return null;
				}
				// Try and just combine in inventory
			} else if (!this.mergeItemStack(stack_active, INV_START, HOTBAR_END, false)) {
				return null;
			}
			// Check for zero size
			if (stack_active.stackSize == 0) {
				// Correct it to null
				slot.putStack(null);
			} else {
				// Notify of Change
				slot.onSlotChanged();
			}
			// Check for no change
			if (stack_active.stackSize == stack_return.stackSize) {
				return null;
			}
			// Notify that picking it up
			slot.onPickupFromSlot(par1EntityPlayer, stack_active);
		}
		// Return what is left
		return stack_return;
	}
}