[Solved] Limiting what goes in inventory slots

[defiant810]

Hey there, quick question:

 

How does one block certain items from going into an inventory (like how the vanilla Furnace doesn't allow non-fuels in the bottom slot)?

 

Right now this is my code in my tile entity:

@Override
public void setInventorySlotContents(int slot, ItemStack toPut)
{
	ItemStack old = getStackInSlot(slot);

	if (toPut != null && (toPut.itemID == Item.stick.shiftedIndex || toPut.itemID == Item.pickaxeWood.shiftedIndex 
			|| toPut.itemID == Item.shovelWood.shiftedIndex))
	{
		inventory[slot] = toPut;

		if (toPut.itemID == Item.stick.shiftedIndex) 
		{
			capsuleContained = CapsuleType.LOW;
		} 
		else if (toPut.itemID == Item.pickaxeWood.shiftedIndex) 
		{
			capsuleContained = CapsuleType.MEDIUM;
		}
		else if (toPut.itemID == Item.shovelWood.shiftedIndex)
		{
			capsuleContained = CapsuleType.HIGH;
		}

		if(toPut.stackSize > getInventoryStackLimit())
		{
			toPut.stackSize = getInventoryStackLimit();
		}
	}
	else if (toPut == null)
	{
		inventory[slot] = toPut;
		capsuleContained = CapsuleType.NONE;
	}
	else
	{
		//It eats other items...
	}
}

 

As of right now, the inventory (of only one slot) only allows sticks, wooden picks, and wooden shovels (testing items). When I try to put other things in, instead of doing nothing, the slot remains empty but the original item disappears. How can I make it so that item doesn't disappear, and just stays in the player's cursor?

 

And yes, I've already looked at the furnace code, it didn't help.

[Parthon]

The vanilla furnace allows non-fuels in the bottom slot, it just doesn't burn them when it's time to get new fuel.

 

There would have to be a function elsewhere that determines what can/can't be put in to a slot, before that function gets called. It seems that setInventorySlotContents happens after the testing, whereever that could be.

[defiant810]

Hmmm... OK, that makes sense.

 

Does anyone out there know if there is a method that defines what can and can't be put into certain slots? Or another way to solve this problem?

[Parthon]

I checked through tileEntity and Iinventory and couldn't find anything useful.

 

What you could do is accept the item into the slot, then poit it out if it's incorrect. Sort of like when the crafting table is closed and everything gets dropped.

[defiant810]

I looked through the same two classes and came up with the same results. I guess the dropping the inventory solution will be good temporarily until I figure out how to block items from slots, if it is possible.

[dmillerw]

You can make a custom slot, which has a method for determining what is a valid item for said slot.

[defiant810]

So I tried making a method that takes the item if it is invalid, sets the slot to null, and ejects the item into the world.

 

Good news: it works.

Bad news: it works twice.

 

Whenever it ejects the ItemStack, it makes one legit version that can be picked up, and then it also ejects a ghost version of the same stack that cant be picked up; it just sits there and mocks you.

 

Here is the TileEntity code:

@Override
public void setInventorySlotContents(int slot, ItemStack toPut)
{
	inventory[slot] = toPut;

	if(toPut != null)
	{
		if(toPut.itemID == Item.stick.shiftedIndex)
		{
			this.capsuleContained = CapsuleType.LOW;
		}
		else if(toPut.itemID == Item.pickaxeWood.shiftedIndex)
		{
			this.capsuleContained = CapsuleType.MEDIUM;	
		}
		else if(toPut.itemID == Item.shovelWood.shiftedIndex)
		{
			this.capsuleContained = CapsuleType.HIGH;
		}
		else
		{
			capsuleContained = CapsuleType.NONE;
			checkSlot(slot);
		}
	}
	else
	{
		capsuleContained = CapsuleType.NONE;
	}

	if(toPut != null && toPut.stackSize > getInventoryStackLimit())
	{
		toPut.stackSize = getInventoryStackLimit();
	}
	}

@Override
protected void checkSlot(int slot)
{
	ItemStack contents = getStackInSlot(slot);

	boolean valid = (contents.itemID == Item.stick.shiftedIndex || 
		contents.itemID == Item.pickaxeWood.shiftedIndex ||
		contents.itemID == Item.shovelWood.shiftedIndex);

	if(!valid)
	{
		inventory[slot] = null;
		dropItem(contents);
	}
}

 

And here is the dropItem method from the super class:

protected void dropItem(ItemStack contents)
{
	Random rand = new Random();

	float rx = rand.nextFloat() * 0.8F + 0.1F;
	float ry = rand.nextFloat() * 0.8F + 0.1F;
	float rz = rand.nextFloat() * 0.8F + 0.1F;

	EntityItem entity = new EntityItem(this.getWorldObj(), this.xCoord + rx, this.yCoord + ry,
		this.zCoord + rz, new ItemStack(contents.itemID, contents.stackSize, contents.getItemDamage()));

	if(contents.hasTagCompound())
	{
		entity.item.setTagCompound((NBTTagCompound)contents.getTagCompound().copy());
	}

	entity.motionX = rand.nextGaussian() * 0.8f;
	entity.motionY = rand.nextGaussian() * 0.8f;
	entity.motionZ = rand.nextGaussian() * 0.8f;
	this.getWorldObj().spawnEntityInWorld(entity);
}

 

I don't see where it could be creating two stacks. This is (almost) the same code I use to eject the items out of my other blocks, and that works just fine.

 

EDIT:

 

Here are the two files that are being used here:

https://github.com/SeanMoss/QuantumCraft/tree/master/src/common/quantumcraft/common/tileentity

[shadowmage4513]

The dupe item would be a client-side spawned item.  Make sure in your code that spawns the entityItem, that it is only called server-side.

 

For custom inventory validation--I used a custom slot and used the isItemValidForSlot method in the slot.  However, I had to use some workarounds in order to get it to work while shift-clicking items. (normal transfer is easy with the slot method).

 

Using this method, I am able to sucessfully tell a 12 slot inventory that it can only accept certain items in slots 0-5, different items in 6-8, and finally a different set it slots 9-11.

 

I can provide links to source if needed.

[defiant810]

A link to source would be massively appreciated. And how would one make sure that the item spawn only happens on the server? Would the @Sided annotation do that, ir does it need to happen some other way?

 

[opssemnik]

if(world.isRemote){

EntityItem entity = new EntityItem(this.getWorldObj(), this.xCoord + rx, this.yCoord + ry,

    this.zCoord + rz, new ItemStack(contents.itemID, contents.stackSize, contents.getItemDamage()));

}

[keepcalm]

if(world.isRemote){

EntityItem entity = new EntityItem(this.getWorldObj(), this.xCoord + rx, this.yCoord + ry,

    this.zCoord + rz, new ItemStack(contents.itemID, contents.stackSize, contents.getItemDamage()));

}

 

What he meant was

if (!world.isRemote){
EntityItem entity = new EntityItem(this.getWorldObj(), this.xCoord + rx, this.yCoord + ry,
    this.zCoord + rz, new ItemStack(contents.itemID, contents.stackSize, contents.getItemDamage()));
}

(you spawn server-side, not client-side)

[opssemnik]

oh thanks kore (its annoying why the dedicated server must return false to the world.isRemote, mojang fails).

[defiant810]

*Facepalm* I completely forgot about the world.isRemote flag.

 

And that appears to have fixed my error, there are no longer any ghost ItemStacks appearing.

 

Thanks to everyone who helped.