Add close callback to CarlaPluginUi, use it in LV2

source/backend/plugin/CarlaPluginUi.cpp

@@ -30,8 +30,9 @@
 class X11PluginUi : public CarlaPluginUi
 {
 public:
-    X11PluginUi() noexcept
-        : fDisplay(nullptr),
+    X11PluginUi(CloseCallback* cb) noexcept
+        : CarlaPluginUi(cb),
+          fDisplay(nullptr),
           fWindow(0)
      {
         fDisplay = XOpenDisplay(0);
@@ -90,6 +91,23 @@ public:
 
     void idle() override
     {
+        for (XEvent event; XPending(fDisplay) > 0;)
+        {
+            XNextEvent(fDisplay, &event);
+
+            switch (event.type)
+            {
+            case ClientMessage:
+                if (std::strcmp(XGetAtomName(fDisplay, event.xclient.message_type), "WM_PROTOCOLS") == 0)
+                {
+                    CARLA_SAFE_ASSERT_BREAK(fCallback != nullptr);
+                    fCallback->handlePluginUiClosed();
+                }
+                break;
+            default:
+                break;
+            }
+        }
     }
 
     void focus() override
@@ -145,23 +163,23 @@ private:
 // -----------------------------------------------------
 
 #ifdef CARLA_OS_MAC
-CarlaPluginUi* CarlaPluginUi::newCocoa()
+CarlaPluginUi* CarlaPluginUi::newCocoa(CloseCallback* cb)
 {
-    return new CocoaPluginUi();
+    return new CocoaPluginUi(cb);
 }
 #endif
 
 #ifdef CARLA_OS_WIN
-CarlaPluginUi* CarlaPluginUi::newWindows()
+CarlaPluginUi* CarlaPluginUi::newWindows(CloseCallback* cb)
 {
-    return new WindowsPluginUi();
+    return new WindowsPluginUi(cb);
 }
 #endif
 
 #ifdef HAVE_X11
-CarlaPluginUi* CarlaPluginUi::newX11()
+CarlaPluginUi* CarlaPluginUi::newX11(CloseCallback* cb)
 {
-    return new X11PluginUi();
+    return new X11PluginUi(cb);
 }
 #endif
 

source/backend/plugin/CarlaPluginUi.hpp

@@ -24,9 +24,13 @@
 
 class CarlaPluginUi
 {
-protected:
-    CarlaPluginUi() noexcept {}
 public:
+    class CloseCallback {
+    public:
+        virtual ~CloseCallback() {}
+        virtual void handlePluginUiClosed() = 0;
+    };
+
     virtual ~CarlaPluginUi() {}
     virtual void show() = 0;
     virtual void hide() = 0;
@@ -37,14 +41,18 @@ public:
     virtual void* getPtr() const noexcept = 0;
 
 #ifdef CARLA_OS_MAC
-    static CarlaPluginUi* newCocoa();
+    static CarlaPluginUi* newCocoa(CloseCallback*);
 #endif
 #ifdef CARLA_OS_WIN
-    static CarlaPluginUi* newWindows();
+    static CarlaPluginUi* newWindows(CloseCallback*);
 #endif
 #ifdef HAVE_X11
-    static CarlaPluginUi* newX11();
+    static CarlaPluginUi* newX11(CloseCallback*);
 #endif
+
+protected:
+    CloseCallback* fCallback;
+    CarlaPluginUi(CloseCallback* cb) noexcept : fCallback(cb) {}
 };
 
 // -----------------------------------------------------

source/backend/plugin/Lv2Plugin.cpp

@@ -331,7 +331,8 @@ struct Lv2PluginOptions {
 
 // -----------------------------------------------------
 
-class Lv2Plugin : public CarlaPlugin
+class Lv2Plugin : public CarlaPlugin,
+                         CarlaPluginUi::CloseCallback
 {
 public:
     Lv2Plugin(CarlaEngine* const engine, const unsigned int id)
@@ -1127,7 +1128,7 @@ public:
 
                 case LV2_UI_COCOA:
 #ifdef CARLA_OS_MAC
-                    fUi.window = CarlaPluginUi::newCocoa();
+                    fUi.window = CarlaPluginUi::newCocoa(this);
 #else
                     msg = "UI is for MacOS only";
 #endif
@@ -1135,7 +1136,7 @@ public:
 
                 case LV2_UI_WINDOWS:
 #ifdef CARLA_OS_WIN
-                    fUi.window = CarlaPluginUi::newWindows();
+                    fUi.window = CarlaPluginUi::newWindows(this);
 #else
                     msg = "UI is for Windows only";
 #endif
@@ -1143,7 +1144,7 @@ public:
 
                 case LV2_UI_X11:
 #ifdef HAVE_X11
-                    fUi.window = CarlaPluginUi::newX11();
+                    fUi.window = CarlaPluginUi::newX11(this);
 #else
                     msg = "UI is only for systems with X11";
 #endif
@@ -1262,7 +1263,9 @@ public:
 
         if (fUi.handle != nullptr && fUi.descriptor != nullptr)
         {
-            if (fUi.type == UI::TYPE_EXTERNAL && fUi.widget != nullptr)
+            if (fUi.type == UI::TYPE_EMBED && fUi.window != nullptr)
+                fUi.window->idle();
+            else if (fUi.type == UI::TYPE_EXTERNAL && fUi.widget != nullptr)
                 LV2_EXTERNAL_UI_RUN((LV2_External_UI_Widget*)fUi.widget);
 
             if (fExt.uiidle != nullptr && fExt.uiidle->idle(fUi.handle) != 0)
@@ -4034,6 +4037,22 @@ public:
         pData->engine->callback(ENGINE_CALLBACK_UI_STATE_CHANGED, pData->id, 0, 0, 0.0f, nullptr);
     }
 
+    void handlePluginUiClosed() override
+    {
+        CARLA_SAFE_ASSERT_RETURN(fUi.type == UI::TYPE_EMBED,);
+        CARLA_SAFE_ASSERT_RETURN(fUi.window != nullptr,);
+        carla_debug("Lv2Plugin::handleExternalUiClosed()");
+
+        fUi.window->hide();
+
+        if (fUi.handle != nullptr && fUi.descriptor != nullptr && fUi.descriptor->cleanup != nullptr)
+            fUi.descriptor->cleanup(fUi.handle);
+
+        fUi.handle = nullptr;
+        fUi.widget = nullptr;
+        pData->engine->callback(ENGINE_CALLBACK_UI_STATE_CHANGED, pData->id, 0, 0, 0.0f, nullptr);
+    }
+
     // -------------------------------------------------------------------
 
     uint32_t handleUiPortMap(const char* const symbol) const noexcept