public void OnGUI()

in unity/Assets/PostProcessingV2/Editor/EffectListEditor.cs [125:199]
62 lines of code
10 McCabe index (conditional complexity)

        public void OnGUI()
        {
            if (m_Asset == null)
                return;

            if (m_Asset.isDirty)
            {
                RefreshEditors();
                m_Asset.isDirty = false;
            }

            bool isEditable = !VersionControl.Provider.isActive
                || AssetDatabase.IsOpenForEdit(m_Asset, StatusQueryOptions.UseCachedIfPossible);

            using (new EditorGUI.DisabledScope(!isEditable))
            {
                EditorGUILayout.LabelField(EditorUtilities.GetContent("Overrides"), EditorStyles.boldLabel);

                // Override list
                for (int i = 0; i < m_Editors.Count; i++)
                {
                    var editor = m_Editors[i];
                    string title = editor.GetDisplayTitle();
                    int id = i; // Needed for closure capture below

                    EditorUtilities.DrawSplitter();
                    bool displayContent = EditorUtilities.DrawHeader(
                        title,
                        editor.baseProperty,
                        editor.activeProperty,
                        editor.target,
                        () => ResetEffectOverride(editor.target.GetType(), id),
                        () => RemoveEffectOverride(id)
                        );

                    if (displayContent)
                    {
                        using (new EditorGUI.DisabledScope(!editor.activeProperty.boolValue))
                            editor.OnInternalInspectorGUI();
                    }
                }

                if (m_Editors.Count > 0)
                {
                    EditorUtilities.DrawSplitter();
                    EditorGUILayout.Space();
                }
                else
                {
                    EditorGUILayout.HelpBox("No override set on this volume.", MessageType.Info);
                }

                if (GUILayout.Button("Add effect...", EditorStyles.miniButton))
                {
                    var menu = new GenericMenu();

                    var typeMap = PostProcessManager.instance.settingsTypes;
                    foreach (var kvp in typeMap)
                    {
                        var type = kvp.Key;
                        var title = EditorUtilities.GetContent(kvp.Value.menuItem);
                        bool exists = m_Asset.HasSettings(type);

                        if (!exists)
                            menu.AddItem(title, false, () => AddEffectOverride(type));
                        else
                            menu.AddDisabledItem(title);
                    }

                    menu.ShowAsContext();
                }

                EditorGUILayout.Space();
            }
        }