UI: Handle update_properties signal in OBSBasicFilters window

The OBSBasicFilters window did not register a handler for the
"update_properties" signal. Now it does. Addresses issue #1028.

Closes jp9000/obs-studio#1036

UI/window-basic-filters.cpp

@@ -158,6 +158,7 @@ inline OBSSource OBSBasicFilters::GetFilter(int row, bool async)
 void OBSBasicFilters::UpdatePropertiesView(int row, bool async)
 {
 	if (view) {
+		updatePropertiesSignal.Disconnect();
 		ui->rightLayout->removeWidget(view);
 		view->deleteLater();
 		view = nullptr;
@@ -173,6 +174,11 @@ void OBSBasicFilters::UpdatePropertiesView(int row, bool async)
 			(PropertiesReloadCallback)obs_source_properties,
 			(PropertiesUpdateCallback)obs_source_update);
 
+	updatePropertiesSignal.Connect(obs_source_get_signal_handler(filter),
+			"update_properties",
+			OBSBasicFilters::UpdateProperties,
+			this);
+
 	obs_data_release(settings);
 
 	view->setMaximumHeight(250);
@@ -181,6 +187,12 @@ void OBSBasicFilters::UpdatePropertiesView(int row, bool async)
 	view->show();
 }
 
+void OBSBasicFilters::UpdateProperties(void *data, calldata_t *)
+{
+	QMetaObject::invokeMethod(static_cast<OBSBasicFilters*>(data)->view,
+			"ReloadProperties");
+}
+
 void OBSBasicFilters::AddFilter(OBSSource filter)
 {
 	uint32_t flags = obs_source_get_output_flags(filter);

UI/window-basic-filters.hpp

@@ -45,6 +45,7 @@ private:
 
 	OBSSignal removeSourceSignal;
 	OBSSignal renameSourceSignal;
+	OBSSignal updatePropertiesSignal;
 
 	inline OBSSource GetFilter(int row, bool async);
 
@@ -56,6 +57,7 @@ private:
 	static void OBSSourceReordered(void *param, calldata_t *data);
 	static void SourceRemoved(void *param, calldata_t *data);
 	static void SourceRenamed(void *param, calldata_t *data);
+	static void UpdateProperties(void *data, calldata_t *params);
 	static void DrawPreview(void *data, uint32_t cx, uint32_t cy);
 
 	QMenu *CreateAddFilterPopupMenu(bool async);