简介

前几天接到一个小单子，需求就是要实现一个物品绑定的功能，被绑定的物品不能从容器中转移（例如丢出、放入/拿出箱子），也就是只能在玩家身上使用。

实现思路

给物品添加特殊的lore标记物品，当物品发生容器转移时检测物品是否含有特殊的lore，若有则取消操作。

核心代码

给物品添加标记lore

if(sender instanceof Player) {
	int selectedLore = Integer.parseInt(args[1]);
	if(selectedLore > _Bind_Lores.size() - 1 || selectedLore < 0) {
		sendMsg(sender, "&c请输入正确的lore编号");
		return;
	}
	String selectedLoreStr = _Bind_Lores.get(selectedLore);
	Player player = (Player) sender;
	ItemStack itemStack = player.getInventory().getItemInMainHand();
	ItemMeta newMeta = itemStack.getItemMeta();
	if(itemStack.getType().equals(Material.AIR)) {
		sendMsg(player, "&c不能绑定空气");
		return;
	}
	List < String > Itemlores = itemStack.getItemMeta().getLore();
	if(Itemlores == null) Itemlores = new ArrayList < > ();
	if(!Itemlores.contains(selectedLoreStr)) Itemlores.add(selectedLoreStr);
	else {
		sendMsg(player, "&c请不要重复绑定");
		return;
	}
	newMeta.setLore(Itemlores);
	itemStack.setItemMeta(newMeta);
	player.getInventory().setItemInMainHand(itemStack);
	sendMsg(sender, "&a物品已绑定");
} else {
	sendMsg(sender, "&c此命令只有玩家可使用");
}

上面的_Bind_Lores是一个存储标记lore的列表。

取消绑定

if(sender instanceof Player) {
	Player player = (Player) sender;
	ItemStack itemStack = player.getInventory().getItemInMainHand();
	ItemMeta newMeta = itemStack.getItemMeta();
	if(itemStack.getType().equals(Material.AIR)) {
		sendMsg(sender, "&c不能解绑定空气");
		return;
	}
	List < String > Itemlores = itemStack.getItemMeta().getLore();
	if(Itemlores == null) Itemlores = new ArrayList < > ();
	Itemlores.removeAll(_Bind_Lores);
	newMeta.setLore(Itemlores);
	itemStack.setItemMeta(newMeta);
	player.getInventory().setItemInMainHand(itemStack);
	sendMsg(sender, "&a物品已解除绑定");
} else {
	sendMsg(sender, "&c此命令只有玩家可使用");
}

事件监听

isIntersection(List<String> o1, List<String> o2)函数用于检测两个列表是否有交集。

丢出物品

@EventHandler
public void onPlayerDropItem(PlayerDropItemEvent event) {
	Player player = event.getPlayer();
	boolean cantBeDropped = isIntersection(_Bind_Lores, event.getItemDrop().getItemStack().getItemMeta().getLore());
	if(cantBeDropped && !player.isOp()) {
                // 允许管理员任意操作被标记的物品
		event.setCancelled(true);
		sendMsg(player, _Anti_Tips);
	}
}

容器转移

// 检查操作
public static boolean checkInventoryAction(InventoryAction action) {
	InventoryAction[] shouldBeChecked = new InventoryAction[] {
		InventoryAction.PICKUP_ALL,
			InventoryAction.PICKUP_HALF,
			InventoryAction.PICKUP_ONE,
			InventoryAction.PICKUP_SOME,
			InventoryAction.PLACE_ALL,
			InventoryAction.PLACE_ONE,
			InventoryAction.PLACE_SOME,
			InventoryAction.MOVE_TO_OTHER_INVENTORY,
			InventoryAction.DROP_ALL_CURSOR,
			InventoryAction.DROP_ONE_CURSOR,
			InventoryAction.DROP_ALL_SLOT,
			InventoryAction.DROP_ONE_SLOT,
			InventoryAction.SWAP_WITH_CURSOR
	};
	for(InventoryAction a: shouldBeChecked) {
		if(a.equals(action)) {
			return true;
		}
	}
	return false;
}
// 事件监听
@EventHandler
public void onInventoryItemMoved(InventoryClickEvent event) {
	InventoryAction action = event.getAction();
	if(event.getCurrentItem() == null || event.getCurrentItem().getItemMeta() == null) return;
	boolean cantBeDropped = checkInventoryAction(action) && isIntersection(_Bind_Lores, event.getCurrentItem().getItemMeta().getLore());
	if(cantBeDropped && !event.getWhoClicked().isOp()) {
                // 允许管理员任意操作被标记的物品
		event.setCancelled(true);
		sendMsg(event.getWhoClicked(), _Anti_Tips);
	}
}