Hi

 

A while back I posted for help with setting up an item with an inventory. I got everything working after much help from diesieben07 (many thanks again). Here is the thread:

 

http://www.minecraftforge.net/forum/index.php/topic,22360.msg114869.html#msg114869

 

After porting to 1.8, things are not working any more. When I reopen the gui, all items placed in the inventory have disappeared. Here are my relevent classes (I am putting spells on a staff, both of which are items):

 

InventoryStaff (setInventorySlotContents() passes the call on to the inventory passed to the constructor. I am writing immediately to the NBTTag)

public class InventoryStaff implements IInventory {

private TagStaff tag;

//These three fields to be used in method setInventorySlotContents
private IInventory parentInventory;
private ItemStack parentStack;
private int parentSlot;

public InventoryStaff(IInventory parentInventory, int parentSlot) {
	this.parentInventory = parentInventory;
	this.parentSlot = parentSlot;
	parentStack = parentInventory.getStackInSlot(parentSlot);
	tag = new TagStaff(parentStack);
}

//IInventory--------------------------------------------------------

@Override
public ItemStack getStackInSlot(int i) {
	return tag.getItemStack(i);
}

@Override
public ItemStack decrStackSize(int i, int amount) {
	ItemStack stack = tag.getItemStack(i);
	tag.setItemStack(i, null);
	return stack;
}

@Override
public ItemStack getStackInSlotOnClosing(int i) {
	//Seems like this is not being called
	System.out.println();
	if (tag.getItemStack(i) != null) {
		ItemStack itemstack = tag.getItemStack(i);
		//Why this?
		tag.setItemStack(i, null);
		return itemstack;
	} else {
		return null;
	}
}

@Override
public void setInventorySlotContents(int i, ItemStack stack) {
	tag.setItemStack(i, stack);
	//These three fields were passed to constructor
	parentInventory.setInventorySlotContents(parentSlot, this.parentStack);
}

@Override
public int getSizeInventory() {
	return Staff.maxNumSpells;
}

@Override
public int getInventoryStackLimit() {
	return 1;
}

@Override
public void markDirty() {
}

@Override
public boolean isUseableByPlayer(EntityPlayer player) {
	return true;
}

@Override
public boolean isItemValidForSlot(int i, ItemStack stack) {
	return true;
}

// ---------------------------------- New 1.8 methods in IInventory

@Override
public String getName() {
	return null;
}

@Override
public boolean hasCustomName() {
	return false;
}

@Override
public IChatComponent getDisplayName() {
	return new ChatComponentText(getName());
}

@Override
public void openInventory(EntityPlayer player) {
	System.out.println();
}

@Override
public void closeInventory(EntityPlayer player) {
}

@Override
public int getField(int id) {
	// TODO Auto-generated method stub
	return 0;
}

@Override
public void setField(int id, int value) {
	// TODO Auto-generated method stub

}

@Override
public int getFieldCount() {
	// TODO Auto-generated method stub
	return 0;
}

@Override
public void clear() {
	//Seems this is not being called
	System.out.println();
	for (int i = 0; i < parentInventory.getSizeInventory(); ++i) {
		setInventorySlotContents(i, null);
	}
}
}

 

TagStaff encapsulates all the complexitity of writing to the tag and it working fine, so I won't post it.

 

GuiStaffContainer:

public class GuiStaffContainer extends Container {

private IInventory inventoryStaff;

public GuiStaffContainer(InventoryPlayer inventoryPlayer, IInventory inventoryStaff) {
	this.inventoryStaff = inventoryStaff;

	for (int i = 0; i < inventoryStaff.getSizeInventory(); i++) {
		//Overrides isItemValid to permit only spells in these slots
		addSlotToContainer(new GuiStaffSlot(inventoryStaff, i, 8 + i * 18, 18));
	}

	for (int i = 0; i < 3; i++) {
		for (int j = 0; j < 9; j++) {
			addSlotToContainer(new Slot(inventoryPlayer, j + i * 9 + 9, 8 + j * 18, 49 + i * 18));
		}
	}

	for (int i = 0; i < 9; i++) {
		addSlotToContainer(new Slot(inventoryPlayer, i, 8 + i * 18, 107));
	}
}

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

 

GuiHandler

public class GuiHandler implements IGuiHandler {

@Override
public Object getServerGuiElement(int id, EntityPlayer player, World w, int x, int y, int z) {
	switch (id) {
	case 3:
		return new GuiStaffContainer(player.inventory, new InventoryStaff(player.inventory,
				player.inventory.currentItem));
	default:
		throw new IllegalArgumentException("GUI id " + id + " is undefined");
	}
}

@Override
public Object getClientGuiElement(int id, EntityPlayer player, World world, int x, int y, int z) {
	switch (id) {
	case 3:
		return new GuiStaff(new GuiStaffContainer(player.inventory, new InventoryStaff(player.inventory,
				player.inventory.currentItem)));
	default:
		throw new IllegalArgumentException("GUI id " + id + " is undefined");
	}
}
}

 

The tag seems to be in sync on both side after placing a spell on the staff:

[16:22:18] [Client thread/INFO] [sTDOUT]: [ds.plato.item.staff.TagStaff:setItemStack:65]: tag={index:0,0:"SpellBox",}
[16:22:18] [server thread/INFO] [sTDOUT]: [ds.plato.item.staff.TagStaff:setItemStack:65]: tag={index:0,0:"SpellBox",}

 

When I close and reopen the gui, the staff has no spells and the tag on the server side is empty:

[16:24:30] [Client thread/INFO] [sTDOUT]: [ds.plato.item.staff.Staff:onItemUse:49]: tag={index:0,0:"SpellBox",}
[16:24:30] [server thread/INFO] [sTDOUT]: [ds.plato.item.staff.Staff:onItemUse:49]: tag={index:0,}

 

I am opening the gui in Staff.onItemUse:

	@Override
public boolean onItemUse(ItemStack stack, EntityPlayer player, World world, BlockPos pos, EnumFacing side, float sx, float sy, float sz) {

	// To compare item stacks on both sides
	System.out.println("tag=" + stack.getTagCompound());

	if (world.isRemote) {
		return true;
	}

	// Open staff gui if space is down
	if (Keyboard.isKeyDown(Keyboard.KEY_SPACE)) {
		player.openGui(Plato.instance, 3, world, 0, 0, 0);
		return true;
	}
}

 

Logic tells me I am doing something elsewhere on the server side which is clearing the tag, but I can't find it. Any help appreciated

world.isRemote returns true on the client side. Keyboard and all other input is also client-side only code, and will definitely crash you on a server when used like that.

 

Anyway, you should open the gui on the server and give it both a server- and client-side element. See this tutorial.

Thanks coolAlias for the reply

 

I had a look at your tutorial, specifically class ItemStore. I think my code is the equivalent of yours. I am returning when the world is remote and opening the gui on the server thread. Here is my Staff.onItemUse() cleaned up a little and commented. I have also overriden getMaxItemUseDuration as you suggest:

 

	@Override
public int getMaxItemUseDuration(ItemStack stack) {
	return 1; // return any value greater than zero
}

@Override
public boolean onItemUse(ItemStack stack, EntityPlayer player, World world, BlockPos pos, EnumFacing side, float sx, float sy, float sz) {

	// To compare item stacks and their tags on both sides
	System.out.println("tag=" + stack.getTagCompound());

	// Return if called from the client thread. We only want the the call from the server side.
	if (world.isRemote) {
		return true;
	}

	// We are on the server side. Open staff gui if space bar is down
	if (Keyboard.isKeyDown(Keyboard.KEY_SPACE)) {
		player.openGui(Plato.instance, GuiHandler.GUI_STAFF, world, (int) player.posX, (int) player.posY,
				(int) player.posZ);
		return true;
	}

	// Get the current spell on the staff and use it
	if (!isEmpty(stack)) {
		Spell s = getSpell(stack);
		s.onItemUse(stack, player, world, pos, side, sx, sy, sz);
		return true;
	}

	return false;
}

 

I am overriding onItemUse() instead of onItemRightClick(), but my guess is that it shouldn't make a difference.

There absolutely is a difference: onItemUse is only called when the player clicks on a block, not in the air; onItemRightClick is called for both.

 

You CAN NOT open the gui on the server from a key press. Read my last reply, read the tutorial. Besides, why are you bothering with a key press when the player is already right-clicking with the item? Just open the gui onItemRightClick.

In your tutorial the opening of your gui on the server is effectively modified by a keypress:

 

@Override
public ItemStack onItemRightClick(ItemStack stack, World world, EntityPlayer player) {
if (!world.isRemote) {
if (!player.isSneaking()) {
player.openGui(TutorialMain.instance, TutorialMain.GUI_ITEM_INV, player.worldObj, (int) player.posX, (int) player.posY, (int) player.posZ);

 

I understand now that player.isSneaking() is not the same as testing for a keypress. Thankyou for pointing that out. I have changed to isSneaking now.

 

I am bothering with the keypress because with no modifier the call is passed on to the current spell on the staff. I need onItemUse because I want the side parameter for use in the spell.

 

Anyway, non of this solves my original problem. When I move new spells from the player's inventory to the staff and reopen the gui, the spells are no longer there.

Sorry, the Minecraft Forum editor seems to have garbled most of the tutorial. Here is the original, and the following is the most important part, updated for 1.8:

/**
 * For inventories stored in ItemStacks, it is critical to implement this method
 * in order to write the inventory to the ItemStack's NBT whenever it changes.
 */
@Override
public void markDirty() {
	for (int i = 0; i < getSizeInventory(); ++i) {
		if (getStackInSlot(i) != null && getStackInSlot(i).stackSize == 0)
			inventory[i] = null;
	}
	writeToNBT(invStack.getTagCompound());
}

In your inventory class, you did not put anything at all in markDirty(), which is why your inventory is not saving.

I pointed this out on my first post, maybe not clearly enough: I do not have a field of type ItemStack[] in my inventory which needs to be written to the tag after every change to the stack array. Instead, I am writing directly to the stack's tag on every call to setInventorySlotContents and decrStackSize. To illustrate the point I have added a println to my previously empty markDirty which prints the current state of the tag to the console:

 

[10:46:00] [Client thread/INFO] [sTDOUT]: [ds.plato.item.staff.InventoryStaff:markDirty:64]: tag=TagStaff [tag={index:0,0:"SpellBox",}]
[10:46:00] [Client thread/INFO] [sTDOUT]: [ds.plato.item.staff.InventoryStaff:markDirty:64]: tag=TagStaff [tag={index:0,0:"SpellBox",}]
[10:46:00] [server thread/INFO] [sTDOUT]: [ds.plato.item.staff.InventoryStaff:markDirty:64]: tag=TagStaff [tag={index:0,0:"SpellBox",}]
[10:46:00] [server thread/INFO] [sTDOUT]: [ds.plato.item.staff.InventoryStaff:markDirty:64]: tag=TagStaff [tag={index:0,0:"SpellBox",}]

Not sure why I am getting two calls from each thread, but you can see that, after adding a box spell to the staff,  the tags on both server and client side are up to date.

 

When I close and reopen the gui I get this in the console from the println in Staff.onItemUse:

 

[10:59:27] [Client thread/INFO] [sTDOUT]: [ds.plato.item.staff.Staff:onItemUse:55]: tag={index:0,0:"SpellBox",}
[10:59:27] [server thread/INFO] [sTDOUT]: [ds.plato.item.staff.Staff:onItemUse:55]: tag={index:0,}

 

Clearly, somewhere along the line, the server side tag has lost the box spell.

Ah, I see. Well, that should work if you're already writing to the containing ItemStack's tag compound. At this point, I suggest comparing your code to mine method by method and seeing what is different.

 

Sorry I can't point out specifically what is wrong, but my guess is it has something to do with your TagStaff object.

Solved my problem. Added one line to InventoryStaff.setInventoryContents to set the tag on the parent stack:

 

	@Override
public void setInventorySlotContents(int slot, ItemStack stack) {
	tag.setStack(slot, stack);
	//Fix for issue #42: Staff loses spells when reopening gui
	parentStack.setTagCompound(tagStaff.getTag());
	parentInventory.setInventorySlotContents(parentSlot, parentStack);
}

 

parentInventory is the inventory containing this inventory

parentSlot the slot this inventory is in.

parentStack is that slot's stack

 

Thanks for the help CoolAlias!