EditorApplication.contextualPropertyMenu

Description

Callback raised whenever the user contex-clicks on a property in an Inspector.

This callback is useful to add custom contextual menu items which can perform operations on a particular property.

using UnityEngine;
using UnityEditor;
using System.Collections;

public class Example : EditorWindow
{
    void OnEnable()
    {
        EditorApplication.contextualPropertyMenu += OnPropertyContextMenu;
    }

    void OnDestroy()
    {
        EditorApplication.contextualPropertyMenu -= OnPropertyContextMenu;
    }

    void OnPropertyContextMenu(GenericMenu menu, SerializedProperty property)
    {
        // show a custom menu item only for Vector3 properties
        if (property.propertyType != SerializedPropertyType.Vector3)
            return;

        // and only when called on a Transform component
        if (property.serializedObject.targetObject.GetType() == typeof(Transform))
            return;

        var propertyCopy = property.Copy();
        menu.AddItem("Randomize Vector", false, () =>
            {
                propertyCopy.vector3Value = Random.insideUnitSphere * 5;
            });
    }
}