Add CutterPlugin::terminate() (#1372)

src/plugins/CutterPlugin.h

@@ -10,10 +10,32 @@ class MainWindow;
 class CutterPlugin 
 {
 public:
-    virtual ~CutterPlugin() {}
+    virtual ~CutterPlugin() = default;
+
+    /**
+     * @brief Initialize the Plugin
+     *
+     * called right when the plugin is loaded initially
+     */
     virtual void setupPlugin() = 0;
+
+    /**
+     * @brief Setup any UI components for the Plugin
+     * @param main the MainWindow to add any UI to
+     *
+     * called after Cutter's core UI has been initialized
+     */
     virtual void setupInterface(MainWindow *main) = 0;
 
+    /**
+     * @brief Shutdown the Plugin
+     *
+     * called just before the Plugin is deleted.
+     * This method is usually only relevant for Python Plugins where there is no
+     * direct equivalent of the destructor.
+     */
+    virtual void terminate() {};
+
     virtual QString getName() const = 0;
     virtual QString getAuthor() const = 0;
     virtual QString getDescription() const = 0;

src/plugins/PluginManager.cpp

@@ -78,6 +78,7 @@ void PluginManager::loadPlugins()
 void PluginManager::destroyPlugins()
 {
     for (CutterPlugin *plugin : plugins) {
+        plugin->terminate();
         delete plugin;
     }
 }

src/plugins/sample-python/sample_python.py

@@ -59,6 +59,9 @@ class CutterSamplePlugin(cutter.CutterPlugin):
         widget = FortuneWidget(main, action)
         main.addPluginDockWidget(widget, action)
 
+    def terminate(self): # optional
+        print("CutterSamplePlugin shutting down")
+
 
 # This function will be called by Cutter and should return an instance of the plugin.
 def create_cutter_plugin():