Add compatibility to old version of Unity while adding new features to support newer version

Author: JLChnToZ

Editor/SceneManagerWindow.cs

@@ -178,8 +178,13 @@ private void DrawElement(Rect rect, int index, bool isActive, bool isFocused) {
                     EditorApplication.isPlaying = false;
                 } else if (EditorSceneManager.SaveCurrentModifiedScenesIfUserWantsTo()) {
                     playScene = true;
-                    var loadedScenes = new List<string>(EditorSceneManager.loadedSceneCount);
-                    for (int i = 0, c = EditorSceneManager.loadedSceneCount; i < c; i++) {
+                    #if UNITY_2022_2_OR_NEWER
+                    int loadedSceneCount = SceneManager.loadedSceneCount;
+                    #else
+                    int loadedSceneCount = SceneManager.sceneCount;
+                    #endif
+                    var loadedScenes = new List<string>(loadedSceneCount);
+                    for (int i = 0; i < loadedSceneCount; i++) {
                         Scene scene = SceneManager.GetSceneAt(i);
                         if (scene.IsValid() && !string.IsNullOrEmpty(scene.path))
                             loadedScenes.Add(scene.path);

Editor/UInspectorPlus/ComponentMethodDrawer.cs

@@ -408,7 +408,12 @@ private void InitMethodParams() {
                         var genericArgs = method.GetGenericArguments();
                         if (parameters.Length > 0) {
                             var firstParam = parameters[0].ParameterType;
-                            if (firstParam.IsGenericMethodParameter) {
+                            #if NETSTANDARD2_1_OR_GREATER
+                            bool isGenericMethodParameter = firstParam.IsGenericMethodParameter;
+                            #else
+                            bool isGenericMethodParameter = firstParam.IsGenericParameter;
+                            #endif
+                            if (isGenericMethodParameter) {
                                 genericArgs[firstParam.GenericParameterPosition] = targetType;
                                 method = method.MakeGenericMethod(genericArgs);
                             } else if (firstParam.ContainsGenericParameters) {
@@ -466,7 +471,7 @@ private void DrawComponent() {
             if (GUILayout.Button(selectedMethodIndex < 0 ? GUIContent.none : methodNames[selectedMethodIndex + 1].content, EditorStyles.popup))
                 ShowSearchPopup();
             if (OnClose != null) {
-                if (GUILayout.Button(EditorGUIUtility.IconContent("Toolbar Minus"), EditorStyles.miniLabel, GUILayout.ExpandWidth(false)))
+                if (GUILayout.Button(EditorGUIUtility.IconContent("Toolbar Minus"), Helper.IconButtonStyle, GUILayout.ExpandWidth(false)))
                     OnClose();
                 EditorGUILayout.EndHorizontal();
             }

Editor/UInspectorPlus/Helpers.cs

@@ -477,6 +477,12 @@ internal static Type GetGenericListType(this Type targetType) {
 
         internal static GUIStyle GetGUIStyle(string styleName) => GUI.skin.FindStyle(styleName) ??
             EditorGUIUtility.GetBuiltinSkin(EditorSkin.Inspector).FindStyle(styleName);
+        
+        #if UNITY_2021_2_OR_NEWER
+        internal static GUIStyle IconButtonStyle => EditorStyles.iconButton;
+        #else
+        internal static GUIStyle IconButtonStyle => EditorStyles.miniButton;
+        #endif
 
         internal static T GetOrDefault<T>(object value, T defaultValue = default) {
             if (value == null) return defaultValue;

Editor/UInspectorPlus/InspectorDrawer.cs

@@ -206,7 +206,7 @@ protected virtual void Draw(bool readOnly) {
             if (allowMethods) {
                 GUILayout.BeginHorizontal();
                 GUILayout.FlexibleSpace();
-                if (GUILayout.Button(EditorGUIUtility.IconContent("Toolbar Plus", "Add Method / Index Properties Watcher"), EditorStyles.miniLabel, GUILayout.ExpandWidth(false))) {
+                if (GUILayout.Button(EditorGUIUtility.IconContent("Toolbar Plus", "Add Method / Index Properties Watcher"), Helper.IconButtonStyle, GUILayout.ExpandWidth(false))) {
                     ComponentMethodDrawer newDrawer = null;
                     newDrawer = new ComponentMethodDrawer(target, targetType) {
                         AllowPrivateFields = allowPrivate,

Editor/UInspectorPlus/MethodPropertyDrawer.cs

@@ -335,10 +335,10 @@ public void Draw(bool readOnly, Rect? rect = null) {
                 hasMatchMenu = DrawAssignButton(rect.HasValue ? (Rect?)Helper.ScaleRect(rect.Value, 1, 0.5F, 0, 0, -EditorGUIUtility.singleLineHeight, -7.5F, 15, 15) : null);
             if (!hasMatchMenu && !readOnly && referenceModeBtn) {
                 if (rect.HasValue) {
-                    if (GUI.Button(rect.Value.ScaleRect(1, 0.5F, 0, 0, -EditorGUIUtility.singleLineHeight, -7.5F, 15, 15), EditorGUIUtility.IconContent("_Menu"), EditorStyles.miniLabel))
+                    if (GUI.Button(rect.Value.ScaleRect(1, 0.5F, 0, 0, -EditorGUIUtility.singleLineHeight, -7.5F, 15, 15), EditorGUIUtility.IconContent("_Menu"), Helper.IconButtonStyle))
                         ShowMenu(rect.Value);
                 } else {
-                    if (GUILayout.Button(EditorGUIUtility.IconContent("_Menu"), EditorStyles.miniLabel, GUILayout.ExpandWidth(false)))
+                    if (GUILayout.Button(EditorGUIUtility.IconContent("_Menu"), Helper.IconButtonStyle, GUILayout.ExpandWidth(false)))
                         ShowMenu(menuButtonRect);
                     if (Event.current.type == EventType.Repaint)
                         menuButtonRect = GUILayoutUtility.GetLastRect();
@@ -449,8 +449,8 @@ private bool DrawAssignButton(Rect? rect) {
                     hasButton = true;
                     if (
                         rect.HasValue ?
-                        GUI.Button(rect.Value, EditorGUIUtility.IconContent("Linked"), EditorStyles.miniLabel) :
-                        GUILayout.Button(EditorGUIUtility.IconContent("Linked"), EditorStyles.miniLabel, GUILayout.ExpandWidth(false))
+                        GUI.Button(rect.Value, EditorGUIUtility.IconContent("Linked"), Helper.IconButtonStyle) :
+                        GUILayout.Button(EditorGUIUtility.IconContent("Linked"), Helper.IconButtonStyle, GUILayout.ExpandWidth(false))
                     ) {
                         drawer.TryApplyValue(rawValue);
                         finishedDrawer = drawer;
@@ -728,9 +728,9 @@ private void DrawUnknownField(bool readOnly, object target, Rect? position = nul
                 return;
             bool clicked;
             if (!position.HasValue)
-                clicked = GUILayout.Button(EditorGUIUtility.IconContent("MoreOptions"), EditorStyles.miniLabel, GUILayout.ExpandWidth(false));
+                clicked = GUILayout.Button(EditorGUIUtility.IconContent("MoreOptions"), Helper.IconButtonStyle, GUILayout.ExpandWidth(false));
             else
-                clicked = GUI.Button(position.Value, EditorGUIUtility.IconContent("MoreOptions"), EditorStyles.miniLabel);
+                clicked = GUI.Button(position.Value, EditorGUIUtility.IconContent("MoreOptions"), Helper.IconButtonStyle);
             if (clicked)
                 InspectorChildWindow.Open(target, true, privateFields, obsolete, true, false, this);
         }