XCharts/Scripts/Editor/PropertyDrawers/TooltipDrawer.cs

using UnityEditor;
using UnityEngine;
using UnityEngine.UI;

namespace XCharts
{
    [CustomPropertyDrawer(typeof(Tooltip), true)]
    public class TooltipDrawer : PropertyDrawer
    {
        private bool m_TooltipModuleToggle = false;

        public override void OnGUI(Rect pos, SerializedProperty prop, GUIContent label)
        {
            Rect drawRect = pos;
            drawRect.height = EditorGUIUtility.singleLineHeight;
            SerializedProperty show = prop.FindPropertyRelative("m_Show");
            SerializedProperty crossLabel = prop.FindPropertyRelative("m_CrossLabel");

            ChartEditorHelper.MakeFoldout(ref drawRect, ref m_TooltipModuleToggle, "Tooltip", show);
            drawRect.y += EditorGUIUtility.singleLineHeight + EditorGUIUtility.standardVerticalSpacing;
            if (m_TooltipModuleToggle)
            {
                EditorGUI.PropertyField(drawRect, crossLabel);
                drawRect.y += EditorGUIUtility.singleLineHeight + EditorGUIUtility.standardVerticalSpacing;
            }
        }

        public override float GetPropertyHeight(SerializedProperty prop, GUIContent label)
        {
            if(m_TooltipModuleToggle)
                return 2 * (EditorGUIUtility.singleLineHeight + EditorGUIUtility.standardVerticalSpacing);
            else
                return 1 * (EditorGUIUtility.singleLineHeight + EditorGUIUtility.standardVerticalSpacing);
        }
    }
}