Fix Windows build (#4892)

rtgui/batchqueue.cc

@@ -436,10 +436,12 @@ void BatchQueue::cancelItems (const std::vector<ThumbBrowserEntryBase*>& items)
             if (entry->thumbnail)
                 entry->thumbnail->imageRemovedFromQueue ();
 
-            const auto func = [](BatchQueueEntry* bqe) -> bool {
-                ::g_remove(bqe->savedParamsFile.c_str());
-                return false;
-            };
+            const auto func =
+                [](BatchQueueEntry* bqe) -> bool
+                {
+                    ::g_remove(bqe->savedParamsFile.c_str());
+                    return false;
+                };
 
             idle_register.add<BatchQueueEntry>(func, entry, true);
         }

rtgui/dirbrowser.cc

@@ -248,13 +248,14 @@ int updateVolumesUI (void* br)
 
 void DirBrowser::winDirChanged ()
 {
-    const auto func = [](gpointer data) -> gboolean {
-        static_cast<DirBrowser*>(data)->updateDirTreeRoot();
+    const auto func =
+        [](DirBrowser* self) -> bool
+        {
+            self->updateDirTreeRoot();
+            return false;
+        };
 
-        return FALSE;
-    };
-
-    idle_register.add(func, this);
+    idle_register.add<DirBrowser>(func, this, false);
 }
 #endif
 

rtgui/filecatalog.cc

@@ -1793,13 +1793,14 @@ void FileCatalog::reparseDirectory ()
 
 void FileCatalog::winDirChanged ()
 {
-    const auto func = [](gpointer data) -> gboolean {
-        static_cast<FileCatalog*>(data)->reparseDirectory();
+    const auto func =
+        [](FileCatalog* self) -> bool
+        {
+            self->reparseDirectory();
+            return false;
+        };
 
-        return FALSE;
-    };
-
-    idle_register.add(func, this);
+    idle_register.add<FileCatalog>(func, this, false);
 }
 
 #else