So i'm pretty new to modding, but i want to add a feature to an item, that gives the player another item into the inventory whenever he uses it on a specific block.

I already have a mecanism that detects the block and stuff but the player.inventory.addItemStackToInventory(new ItemStack(Items.ITEM)); function is not working. Is it because of 1.18?

Or am I using it wrong?

This is the code I use, partially copied from the internet XD

	@Override
	public InteractionResultHolder<ItemStack> use(Level world, Player player, InteractionHand hand) {
		
		if (!world.isClientSide()) {
			System.out.println(player.getName().getString() + " used Item lul.");
		    boolean isFluid = false;
		    HitResult block =  player.pick(20.0D, 0.0F, isFluid);
		    
		     if(block.getType() == HitResult.Type.BLOCK)
		      {
		        BlockPos blockpos = ((BlockHitResult)block).getBlockPos();
		        BlockState blockstate = player.level.getBlockState(blockpos);
		        System.out.println("Looking at: "+blockstate.getBlock()+"\nIs Fluid: "+isFluid+"\nPosition= "+ blockpos.getX() + ", " + blockpos.getY() + ", " + blockpos.getZ());
		        if (blockstate.getBlock() == Blocks.OBSIDIAN)
		        {
		        	player.inventory.addItemStackToInventory(new ItemStack(Items.BOWL));
		        	
		        }
		        
		      }
		}
		
		return super.use(world, player, hand);
	}

 

Oh yeah, sure sorry

so there is an error on the .inventory part that says "The field Player.inventory is not visible"

I really don't know what that means and I have seen so many people says that it worked for them...

7 minutes ago, diesieben07 said:

Basic Java knowledge is required obviously.

Yeah I'm kinda trying to pick that up on my way...

Can't you just tell me real quick if it's that obvious?

Or do you have a tip for optaining said basic knowledge?

Use "getinventory()" instead of "inventory"

If you go in the player class, you will see that it say "public static" instead of "private" private can only be seen in one class, so use the "getInventory"

Edited March 25, 20223 yr by Azarsra

If you're wonder the "inventory" method, says private, so it can only be used in the player class, I hope this helps anyone.

Quote

 getInventory()

Well, thank you, @Azarsra, that's a much nicer way of helping people.

Also for anybody having the same problem, you'll have to use

player.getInventory().add(new ItemStack(Items.ITEM, QUANTITY));

 

Instead of addItemStackToInventory(...).

Glad I can help, and remember coding will always have set backs, the thing that makes coding special is a person's will to keep going until they succeed.

@diesieben07Like I said, I am currently trying to learn java. Do you have any good websites or tutorials to do so?

And is that correct, the player class is private, so I can't overwrite any values, but have to use GET?

@Hannos While I do Love helping people, diesieben07 is right, You Must atleast try to understand the Code I am telling you to use, That way You can Write code without having to post/look on forums just to get something to work

For example getInventory() is public, and at the beginning of your code, it says public, which means you can use it in other classes, but if you switch that to private, it will not be able to be used in other classes. I hope you understand that.

I am aware of how public and private works, however, I don't know where I can see/change it. I believe it is in that class System, in already set up code by forge, right?

I am familiar with other languages and Java has some interesting new mechanics...

25 minutes ago, Hannos said:

I don't know where I can see/change it.

you can use your IDE to look into vanilla classes

26 minutes ago, Hannos said:

I believe it is in that class System, in already set up code by forge, right?

do you mean the Access Transformer

22 hours ago, Luis_ST said:

you can use your IDE to look into vanilla classes

Yes, I suspected that... I am currently working with eclipse, is that a good choice?

And how can I do it there?

22 hours ago, Luis_ST said:

do you mean the Access Transformer

Yes, exactly what I meant.

Hi!

51 minutes ago, Hannos said:

I am currently working with eclipse

You can ctrl-click on class and function names on eclipse to get to the source. Additionally, you can find the whole source in your project browser.

52 minutes ago, Hannos said:

is that a good choice?

This is just preference. I like eclipse but I don't know if you do.

please, stop. do not use access transformers.   (and, i managed to say that in nice small lowercase letters)

 

only use access transformers if you satisfy two conditions:
1) you understand why original developers made the field private and/or final.
2) you reasonably expect that changing that will not break anything.

can you tell us that you understand why inventory field was made private and final?

16 hours ago, MFMods said:

please, stop. do not use access transformers.

Yeah, I expected that I would get into trouble if I did...

 

16 hours ago, MFMods said:

 (and, i managed to say that in nice small lowercase letters)

Well, thank you!

 

16 hours ago, MFMods said:

can you tell us that you understand why inventory field was made private and final?

No, I cannot (without lying)

Can you tell me?

1 hour ago, Hannos said:

No, I cannot (without lying)

Can you tell me?

because there is a getter for the inventory

1 hour ago, Luis_ST said:

because there is a getter for the inventory

Ok, but if I look at the code, it literally says:

   public Inventory getInventory() {
      return this.inventory;
   }

It is currently unclear to me, why there is a getter for it when all it does is returning the inventory field itself.

you should really learn the basics of java, since these two code parts does the same thing:

this.inventory.foo();

or

player.getInventory().foo();

i hope this make the whole thing clearer

4 hours ago, Hannos said:

for it when all it does is returning the inventory field itself.

Because you can't access inventory there's a getter that "gets" it for you

13 hours ago, Hannos said:

It is currently unclear to me, why there is a getter for it when all it does is returning the inventory field itself.

they forced users of the Player class to access inventory through getter. so, you can write
      player.getInventory().whatsInSlot15()  
or 
      player.getInventory().putIntoSomeSlot(something),  
but you can not write 
      player.inventory = myInventoryThatIJustCreated
and break everything.  Actually, you can. just use access transformers.

Edited March 31, 20223 yr by MFMods

11 hours ago, MFMods said:

Useful stuff

Thanks man @MFMods, the others didn't really understand my question...

I think I get it now. I'ma watch some java tutorials and study informatics.

thanks for the help anyway and have a nice day!

On 3/27/2022 at 4:51 AM, diesieben07 said:

Except it doesn't help you at all. You now just copied this without understanding why this is the case. Next time you have a similar problem you'll have to ask the same question again. You must learn basic Java before writing a mod. It is a necessary prerequisite. Do not pass go. Do not collect $200.

There's a way to show people the error in their ways, without being an elitist asshole. 

This is not that way.