Add typefind element to pad menu

Allow to add and detect pad caps by typefind.

src/GraphDisplay.cpp

@@ -545,6 +545,7 @@ void GraphDisplay::showContextMenu(QMouseEvent *event)
 		menu.addAction(new CustomMenuAction("Render", &menu));
 		menu.addAction(new CustomMenuAction("Render anyway", &menu));
 		menu.addAction(new CustomMenuAction("Pad properties", &menu));
+		menu.addAction(new CustomMenuAction("typefind", "ElementName", &menu));
 	}
 	else if(elementId != ((size_t)-1))
 	{
@@ -627,8 +628,8 @@ void GraphDisplay::showContextMenu(QMouseEvent *event)
 				requestPad(elementId);
 			else if (pact -> getName() == "Remove selected")
 				removeSelected();
-			else if(pact->getName() == "ElementName")
+			else if (pact->getName() == "ElementName")
-				addPlugin(pact->text());
+				connectPlugin(elementId, pact->text());
 		}
 	}
 }
@@ -672,11 +673,14 @@ void GraphDisplay::removePlugin(std::size_t id)
 	}
 }
 
-void GraphDisplay::addPlugin(const QString& name)
+void GraphDisplay::connectPlugin(std::size_t elementId, const QString& name)
 {
+  ElementInfo* element = getElement(elementId);
+  gchar* pluginName = m_pGraph->AddPlugin(name.toStdString().c_str(), NULL);
+   m_pGraph->Connect(element->m_name.c_str(), pluginName);
+   g_free(pluginName);
 }
 
-
 void GraphDisplay::showElementProperties(std::size_t id)
 {
 	ElementInfo* element = getElement(id);
@@ -712,7 +716,6 @@ void GraphDisplay::renderPad(std::size_t elementId, std::size_t padId, bool caps
 
 	for (l = plugins_list; l != NULL; l = l->next) {
 	    Plugin* plugin = (Plugin*)(l->data);
-	    if (m_pGraph->CanConnect(element->m_name.c_str(), pad->m_name.c_str() , plugin->getName().toStdString().c_str())) {
 	    if (m_pGraph->CanConnect(element->m_name.c_str(), pad->m_name.c_str() , plugin->getName().toStdString().c_str(), capsAny)) {
 	      gchar* pluginName = m_pGraph->AddPlugin(plugin->getName().toStdString().c_str(), NULL);
 	      m_pGraph->Connect(element->m_name.c_str(), pluginName);

src/GraphDisplay.h

@@ -79,7 +79,7 @@ private:
 	QPoint getPadPosition(std::size_t elementId, std::size_t padId);
 	void disconnect(std::size_t elementId, std::size_t padId);
 	void requestPad(std::size_t elementId);
-	void addPlugin(const QString& name);
+	void connectPlugin(std::size_t elementId, const QString& destElementName);
 
 	ElementInfo* getElement(std::size_t elementId);
 	PadInfo* getPad(std::size_t elementId, std::size_t padId);

src/GraphManager.cpp

@@ -22,6 +22,16 @@ gchar* get_str_caps_limited(gchar* str)
   return result;
 }
 
+static void
+typefind_have_type_callback (GstElement * typefind,
+    guint probability, GstCaps * caps, GraphManager * thiz)
+{
+  gchar *caps_description = gst_caps_to_string (caps);
+  qDebug() << "Found caps " << caps_description << " with probability " << probability;
+  g_free(caps_description);
+  thiz->Pause();
+}
+
 GraphManager::GraphManager()
 {
 	m_pGraph = gst_pipeline_new ("pipeline");
@@ -227,6 +237,14 @@ bool GraphManager::Connect(const char *srcElement, const char *dstElement)
 
   gboolean seekRes = gst_element_seek_simple(m_pGraph, GST_FORMAT_TIME, GST_SEEK_FLAG_FLUSH, 0);
 
+  /* add a callback to handle have-type signal */
+  if (g_str_has_prefix(dstElement,"typefindelement")) {
+      g_signal_connect (dst, "have-type",
+          G_CALLBACK (typefind_have_type_callback),
+          this);
+      Play();
+  }
+
   gst_object_unref(src);
   gst_object_unref(dst);
 
@@ -420,7 +438,7 @@ bool GraphManager::Play()
 		qDebug() << "state changing to Play was FAILED";
 	}
 
-	return res == GST_STATE_PLAYING;
+	return state == GST_STATE_PLAYING;
 }
 
 
@@ -437,10 +455,9 @@ bool GraphManager::Pause()
 		qDebug() << "state changing to Pause was FAILED";
 	}
 
-	return res == GST_STATE_PAUSED;
+	return state == GST_STATE_PAUSED;
 }
 
-
 bool GraphManager::Stop()
 {
 	GstStateChangeReturn res = gst_element_set_state(m_pGraph, GST_STATE_READY);