2. Content Provider

Now, you maybe want to know how to put items in your new inventory. To do that, you'll need to create a new InventoryProvider.

InventoryProvider is an interface, so you just need to implements it, example:

public class MyProvider implements InventoryProvider {

    @Override
    public void init(Player player, InventoryContents contents) {}

    @Override
    public void update(Player player, InventoryContents contents) {}

}

Here, the method init will be called when an inventory is opened for the player, and the method update will be called every tick for the players with the inventory opened.

To put the items in the inventory, you just have to use the methods of the given InventoryContents, like fillRow(row, item). Theses methods requires a ClickableItem, which is just an ItemStack combined with a Consumer<InventoryClickEvent>.

To create a ClickableItem, you just have to use ClickableItem.of(ItemStack, Consumer<InventoryClickEvent>), or Clickable.empty(ItemStack) to create an item with an empty consumer, example:

ClickableItem item = ClickableItem.of(new ItemStack(Material.POTATO_ITEM, 2), e -> {
    Bukkit.broadcastMessage(ChatColor.DARK_AQUA + "A potato has been clicked");
});

All the SmartInvs methods which asks for a row and a column have an overload method which asks for a SlotPos you can build using SlotPos.of(row, column), these SlotPos are totally immutables.

This is a list of all the InventoryContents methods you can use to play with the inventory items:

Method	Description
all()	Returns all the inventory items
get(row, column)	Returns the items at the given row and column
set(row, column, item)	Sets the item at the given row and column
firstEmpty()	Returns the first empty slot
add(item)	Adds the item to the first empty slot, if possible
fill(item)	Fills the inventory with the given item
fillRow(row, item)	Fills the given row with the given item
fillColumn(column, item)	Fills the given column with the given item
fillBorders(item)	Fills the inventory borders with the given item
fillRect(fromRow, fromColumn, toRow, toColumn, item)	Fills a rectangle made of the given boundaries with the given item

If you need to set properties to your InventoryContents, you can use the setProperty(String name, Object value) method, to get the properties, use property(String name) or property(String name, T def) to provide a default value.

Each opened inventory has a different InventoryContents, so when you create an iterator or set a property, it will only be saved for the opened inventory o the actual player.

Example

public class MyProvider implements InventoryProvider {

    @Override
    public void init(Player player, InventoryContents contents) {
        for(int i = 0; i < 9; i += 2)
            contents.fillColumn(i, ClickableItem.empty(new ItemStack(Material.BEDROCK)));

        contents.set(1, 1, ClickableItem.of(new ItemStack(Material.COMPASS), e -> {
            if(e.isLeftClick()) {
                player.sendMessage(ChatColor.GOLD + "You left clicked on my compass! "
                        + ChatColor.YELLOW + "Here is a carrot, you deserve it.");

                contents.set(1, 1, ClickableItem.empty(new ItemStack(Material.CARROT_ITEM)));
            }
            else if(e.isRightClick()) {
                player.sendMessage(ChatColor.DARK_RED + "Oh no! The right click was trapped! "
                        + ChatColor.RED + "You found a stick...");

                contents.set(1, 1, ClickableItem.empty(new ItemStack(Material.STICK)));
            }
        }));
    }


    @Override
    public void update(Player player, InventoryContents contents) {}

}

And this is the result of this provider, when applied to a basic chest inventory with 3 rows:

In this example, I didn't used the update method, but you can use it exactly like the init method.