List Drawer Settings Attribute

[PropertyOrder(int.MinValue), OnInspectorGUI]
private void DrawIntroInfoBox()
{
    SirenixEditorGUI.InfoMessageBox("Out of the box, Odin significantly upgrades the drawing of lists and arrays in the inspector - across the board, without you ever lifting a finger.");
}

[Title("List Basics")]
[InfoBox("List elements can now be dragged around to reorder them and deleted individually, and lists have paging (try adding a lot of elements!). You can still drag many assets at once into lists from the project view - just drag them into the list itself and insert them where you want to add them.")]
public List<float> FloatList;

[InfoBox("Applying a [Range] attribute to this list instead applies it to all of its float entries.")]
[Range(0, 1)]
public float[] FloatRangeArray;

[InfoBox("Lists can be made read-only in different ways.")]
[ListDrawerSettings(IsReadOnly = true)]
public int[] ReadOnlyArray1 = new int[] { 1, 2, 3 };

[ReadOnly]
public int[] ReadOnlyArray2 = new int[] { 1, 2, 3 };

public SomeOtherStruct[] SomeStructList;

[Title("Advanced List Customization")]
[InfoBox("Using [ListDrawerSettings], lists can be customized in a wide variety of ways.")]
[ListDrawerSettings(NumberOfItemsPerPage = 5)]
public int[] FiveItemsPerPage;

[ListDrawerSettings(ShowIndexLabels = true, ListElementLabelName = "SomeString")]
public SomeStruct[] IndexLabels;

[ListDrawerSettings(DraggableItems = false, ShowFoldout = false, ShowIndexLabels = true, ShowPaging = false, ShowItemCount = false,
                    HideRemoveButton = true)]
public int[] MoreListSettings = new int[] { 1, 2, 3 };

[ListDrawerSettings(OnBeginListElementGUI = "BeginDrawListElement", OnEndListElementGUI = "EndDrawListElement")]
public SomeStruct[] InjectListElementGUI;

[ListDrawerSettings(OnTitleBarGUI = "DrawRefreshButton")]
public List<int> CustomButtons;

[ListDrawerSettings(CustomAddFunction = "CustomAddFunction")]
public List<int> CustomAddBehaviour;

[Serializable]
public struct SomeStruct
{
    public string SomeString;
    public int One;
    public int Two;
    public int Three;
}

[Serializable]
public struct SomeOtherStruct
{
    [HorizontalGroup("Split", 55), PropertyOrder(-1)]
    [PreviewField(50, Sirenix.OdinInspector.ObjectFieldAlignment.Left), HideLabel]
    public UnityEngine.MonoBehaviour SomeObject;

    [FoldoutGroup("Split/$Name", false)]
    public int A, B, C;

    [FoldoutGroup("Split/$Name", false)]
    public int Two;

    [FoldoutGroup("Split/$Name", false)]
    public int Three;

    private string Name { get { return this.SomeObject ? this.SomeObject.name : "Null"; } }
}

private void BeginDrawListElement(int index)
{
    SirenixEditorGUI.BeginBox(this.InjectListElementGUI[index].SomeString);
}

private void EndDrawListElement(int index)
{
    SirenixEditorGUI.EndBox();
}

private void DrawRefreshButton()
{
    if (SirenixEditorGUI.ToolbarButton(EditorIcons.Refresh))
    {
        Debug.Log(this.CustomButtons.Count.ToString());
    }
}

private int CustomAddFunction()
{
    return this.CustomAddBehaviour.Count;
}