Linking a Collection to Its Extension

During the creation wizard, you will be given the choice to send an optional payload, the payload is an encoded ABI string useful to trigger a lazy initialization of the Extension.

Looking at the “init()” method of the previous example, in the Collection Creation Wizard we will pass the payload “0xe1c7392a” (the first 4 bytes of the keccak256 version of the “init()” string). Doing so makes the Collection call the Extension using this payload.

As you can see in the “init()” function body, the msg.sender of the call is the brand-new Collection itself, which will now be linked to its extension. If you are the host of a Collection you can mint new Items by calling:

function mint(uint256 amount, string calldata tokenName, string calldata tokenSymbol, string calldata objectUri) external returns (uint256 objectId, address tokenAddress);

You need to pass the amount to mint, name, and symbol (which can be left blank; in this case, the original collection name and symbol will be used), and, finally, the uri of the metadata.

Make ITEMs Mintable

Once the ITEM is created with its specific amount, it is not possible to mint more of it. If you want to have an ITEM which will let you mint more in the future, you have to use the call:

function mint(uint256 amount, string calldata tokenName, string calldata tokenSymbol, string calldata objectUri, bool editable) external returns (uint256 objectId, address tokenAddress); 

If editable is true, it will be possible to mint more of it in the future. To mint more of the previously created item, you need to call

function mint(uint256 objectId, uint256 amount) external;

passing the objectId of the ITEM and the new amount to create. If you want to disable the minting of a token, you, as an Extension, have to call the method

function makeReadOnly(uint256 objectId);

This call is irreversible and will not let a new amount of this item be minted anymore.