Fix custom icon overrides not working for Qt builtin controls

src/calibre/gui2/__init__.py

@@ -1332,7 +1332,20 @@ class Application(QApplication):
             '#FF2400' if is_error else '#50c878')
 
     def load_calibre_style(self):
+        from calibre.utils.resources import get_user_path
         icon_map = self.__icon_map_memory_ = {}
+        user_path = get_user_path()
+        if user_path:
+            user_path = os.path.join(user_path, 'images')
+
+        @lru_cache(maxsize=64)
+        def check_for_custom_icon(v):
+            if user_path:
+                q = os.path.join(user_path, v)
+                if os.path.exists(q):
+                    return q
+            return v.rpartition('.')[0]
+
         for k, v in {
             'DialogYesButton': 'ok.png',
             'DialogNoButton': 'window-close.png',
@@ -1353,7 +1366,7 @@ class Application(QApplication):
             'ToolBarHorizontalExtensionButton': 'v-ellipsis.png',
             'ToolBarVerticalExtensionButton': 'h-ellipsis.png',
         }.items():
-            icon_map[getattr(QStyle.StandardPixmap, 'SP_'+k).value] = v.rpartition('.')[0]
+            icon_map[getattr(QStyle.StandardPixmap, 'SP_'+k).value] = check_for_custom_icon(v)
         transient_scroller = 0
         if ismacos:
             from calibre_extensions.cocoa import transient_scroller

src/calibre/gui2/progress_indicator/QProgressIndicator.cpp

@@ -158,6 +158,8 @@ int CalibreStyle::styleHint(StyleHint hint, const QStyleOption *option, const QW
 
 QIcon CalibreStyle::standardIcon(StandardPixmap standardIcon, const QStyleOption * option, const QWidget * widget) const {
     if (icon_map.contains(standardIcon)) {
+        QString q = icon_map.value(standardIcon);
+        if (q.contains('.')) return QIcon(q);
         QIcon ans = QIcon::fromTheme(icon_map.value(standardIcon));
         if (ans.isNull() && QIcon::themeName().contains("user-any")) {
             const bool is_dark_theme = QApplication::instance()->property("is_dark_theme").toBool();

src/calibre/utils/resources.py

@@ -101,5 +101,9 @@ def set_data(path, data=None):
     return _resolver.set_data(path, data)
 
 
+def get_user_path():
+    return _resolver.user_path
+
+
 builtins.__dict__['P'] = get_path
 builtins.__dict__['I'] = get_image_path