So I was playing around with fluids in guis and when I try to put a fluid into a tank using the method from the FluidContainerRegistry, it always returns null. Even if I put a water bucket or a lava bucket. If I try to put in a fluid without using that method, just defining one like: FluidStack fluid = new FluidStack(Mod.fluid, bucketSize); it works, but not when I'm using the method to get the the fluid out of the bucket.

 

TileEntity Code:

 

(The only important part is updateEntity(), all other code works fine and is tested, so I'm just posting that method)

 

    @Override
    public void updateEntity()
    {
        FluidStack fluid = tank.getFluid();
        int bucketSize = FluidContainerRegistry.BUCKET_VOLUME;

        if (!worldObj.isRemote)
        {
            ItemStack stack = items[0];

            if (stack != null)
            {
                FluidStack liquid  = null;
                
                if (stack.getItem().getContainerItem() != null)
                {
                    liquid = FluidContainerRegistry.getFluidForFilledItem(stack);
                }

                if (liquid != null)
                {
                    if (fill(ForgeDirection.UNKNOWN, liquid, false) == liquid.amount)
                    {
                        fill(ForgeDirection.UNKNOWN, liquid, true);
                        setInventorySlotContents(0, consumeItem(stack)); //consumes the item (for method look down below)
                    }
                }
            }

            if (items[1] != null)
            {
                if (FluidContainerRegistry.isBucket(items[1]))
                {
                    if (tank.getFluid() != null)
                    {
                        if (tank.getFluidAmount() >= bucketSize)
                        {
                            setInventorySlotContents(1, FluidContainerRegistry.fillFluidContainer(tank.getFluid(), items[1]));
                            drain(ForgeDirection.UNKNOWN, tank.getFluid(), bucketSize, true);
                        }
                    }
                }
            }
        }
    }

 

I've got two slots; one for filling and one for draining a bucket. The drain() and fill() methods are both working, there is nothing wrong there.

 

consumeItem(ItemStack stack):

 

    public static ItemStack consumeItem(ItemStack stack)
    {
        if (stack.stackSize == 1)
        {
            if (stack.getItem().getContainerItem() != null)
            {
                return stack.getItem().getContainerItem(stack);
            }
            else
            {
                return null;
            }
        }
        else
        {
            stack.splitStack(1);

            return stack;
        }
    }

 

Thanks for any help!

I've also noticed that the fillFluidContainer(FluidStack fluid, ItemStack container) also returns null, is this an error/problem on my side of coding or does the Forge code simply not work. Would be grateful for any answer.

Check your version of Forge. Before 10.12.0.1034 there were quite a lot bugs in the fluid api that resulted in problems like you are describing. The only other thing I can think of is that your itemstack is invalid (null or not a registered fluid container).

That fixed it, needed to update forge, 1+ for you