ItemStack bug in the container

[LuccaPossamai]

I was creating a container, and, to do this, I looked the DispenserContainer to understand the methods. So I created the container and added the slots(of container and player inventory). But, when I open the container, the item in the container slots or in the player inventory slots duplicate, and one of them its in my cursor(the image explain better). I'd like to know if its a bug or an error in the code writing. Thanks.  

[Luis_ST]

2 hours ago, LuccaPossamai said:

I was creating a container, and, to do this, I looked the DispenserContainer to understand the methods. So I created the container and added the slots(of container and player inventory). But, when I open the container, the item in the container slots or in the player inventory slots duplicate, and one of them its in my cursor(the image explain better). I'd like to know if its a bug or an error in the code writing. Thanks.

show your code of your container
it could be that you do not synchronize the inventory of the container between server and client

[LuccaPossamai]

I already fixed it. Don't know how but, when I remove the containerId from the constructor as an integer, this bug won't happen.