c# - 允许选定子对象的 Unity 自定义检查器

Question

我正在尝试为 PlayerInventory 类创建自定义检查器。 PlayerInventory 类由项目列表(ScriptableObjects)以及每个项目的数量组成，如下所示:

public class Item : ScriptableObject
{
   public string description;
   public Sprite picture;
}

public class InventoryItem : ScriptableObject
{
   // A reference to the Item object that contains the item's description, 
   // picture, stats, etc.
   public Item item;

   // The quantity of this item that the player has in his inventory
   public int quantity;
}

[CreateAssetMenu(menuName = "Player/Player Inventory")]
public class PlayerInventory : ScriptableObject
{
   // The list of each distinct item that the player has in his inventory,
   // along with the quantity of each item
   public List<InventoryItem> items;
}

我创建了一个 PlayerInventory 实例作为游戏 Assets 。默认情况下，Inspector 会显示一个 InventoryItem 列表。但是，我想要的是让 Inspector 显示每个 InventoryItem 元素，其中包含一个为其选择 Item 的字段、一个输入数量的字段和一个“删除”按钮。

这是我试图实现的目标的可视化示例，以及下面的当前代码。此屏幕截图的问题在于 Unity 让我为每个元素选择一个 InventoryItem 对象。我希望能够为每个元素选择一个 Item 对象。我遇到的第二个问题是我不知道如何将 EditorGUILayout.TextField 设置为 InventoryItem.quantity 属性，因为我不知道如何将SerializedProperty 到 InventoryItem 对象。

[CustomEditor(typeof(PlayerInventory))]
public class PlayerInventoryEditor : Editor
{
   public override void OnInspectorGUI()
   {
       this.serializedObject.Update();

       SerializedProperty items = this.serializedObject.FindProperty("items");
       for (int i = 0; i < items.arraySize; i++)
       {
           EditorGUILayout.BeginHorizontal();
           EditorGUILayout.LabelField("Item", GUILayout.Width(50));

           // I don't know how to make this line reference the child "item"
           // field of the current InventoryItem
           EditorGUILayout.PropertyField(items.GetArrayElementAtIndex(i), GUIContent.none, GUILayout.Width(170));

           EditorGUILayout.LabelField("    Quantity", GUILayout.Width(80));

           // I don't know how to set the text field to the "quantity" field
           // of the current InventoryItem
           EditorGUILayout.TextField("0", GUILayout.Width(50));

           EditorGUILayout.LabelField("", GUILayout.Width(20));
           GUILayout.Button("Delete Item");               
           EditorGUILayout.EndHorizontal();
       }

       GUILayout.Button("Add Item");
   }
}

Answer 1

类必须是可序列化的才能出现在检查器中。参见 Serializable

编辑。在下面的评论中进一步讨论后，这里是完整的片段；

标有Serializable的标准类；

[System.Serializable]
public class InventoryItem
{
    public Item item;
    public int quantity;
}

使用 PlayerInventoryEditor；

public override void OnInspectorGUI ()
{
    this.serializedObject.Update();

    SerializedProperty items = this.serializedObject.FindProperty("items");

    for (int i = 0; i < items.arraySize; i++)
    {
        SerializedProperty item = items.GetArrayElementAtIndex(i);

        EditorGUILayout.BeginHorizontal();
        EditorGUILayout.LabelField("Item", GUILayout.Width(50));
        EditorGUILayout.PropertyField(item.FindPropertyRelative("item"), GUIContent.none, GUILayout.Width(170));
        EditorGUILayout.LabelField("    Quantity", GUILayout.Width(80));
        EditorGUILayout.IntField(item.FindPropertyRelative("quantity").intValue, GUILayout.Width(50));

        EditorGUILayout.LabelField("", GUILayout.Width(20));
        GUILayout.Button("Delete Item");
        EditorGUILayout.EndHorizontal();
    }

    GUILayout.Button("Add Item");
}