Windows: Use timer to update VBlank registration for embedded HWNDComponentPeer

modules/juce_gui_basics/native/juce_win32_Windowing.cpp

@@ -1641,6 +1641,31 @@ private:
 
 JUCE_IMPLEMENT_SINGLETON (VBlankDispatcher)
 
+//==============================================================================
+class SimpleTimer  : private Timer
+{
+public:
+    SimpleTimer (int intervalMs, std::function<void()> callbackIn)
+        : callback (std::move (callbackIn))
+    {
+        jassert (callback);
+        startTimer (intervalMs);
+    }
+
+    ~SimpleTimer() override
+    {
+        stopTimer();
+    }
+
+private:
+    void timerCallback() override
+    {
+        callback();
+    }
+
+    std::function<void()> callback;
+};
+
 //==============================================================================
 class HWNDComponentPeer  : public ComponentPeer,
                            private VBlankListener,
@@ -1682,8 +1707,10 @@ public:
             return ModifierKeys::currentModifiers;
         };
 
-        if (updateCurrentMonitor())
-            VBlankDispatcher::getInstance()->updateDisplay (*this, currentMonitor);
+        updateCurrentMonitorAndRefreshVBlankDispatcher();
+
+        if (parentToAddTo != nullptr)
+            monitorUpdateTimer.emplace (1000, [this] { updateCurrentMonitorAndRefreshVBlankDispatcher(); });
 
         suspendResumeRegistration = ScopedSuspendResumeNotificationRegistration { hwnd };
     }
@@ -3675,10 +3702,18 @@ private:
         return 0;
     }
 
-    bool updateCurrentMonitor()
+    enum class ForceRefreshDispatcher
+    {
+        no,
+        yes
+    };
+
+    void updateCurrentMonitorAndRefreshVBlankDispatcher (ForceRefreshDispatcher force = ForceRefreshDispatcher::no)
     {
         auto monitor = MonitorFromWindow (hwnd, MONITOR_DEFAULTTONULL);
-        return std::exchange (currentMonitor, monitor) != monitor;
+
+        if (std::exchange (currentMonitor, monitor) != monitor || force == ForceRefreshDispatcher::yes)
+            VBlankDispatcher::getInstance()->updateDisplay (*this, currentMonitor);
     }
 
     bool handlePositionChanged()
@@ -3697,9 +3732,7 @@ private:
         }
 
         handleMovedOrResized();
-
-        if (updateCurrentMonitor())
-            VBlankDispatcher::getInstance()->updateDisplay (*this, currentMonitor);
+        updateCurrentMonitorAndRefreshVBlankDispatcher();
 
         return ! dontRepaint; // to allow non-accelerated openGL windows to draw themselves correctly.
     }
@@ -3857,8 +3890,7 @@ private:
 
         auto* dispatcher = VBlankDispatcher::getInstance();
         dispatcher->reconfigureDisplays();
-        updateCurrentMonitor();
-        dispatcher->updateDisplay (*this, currentMonitor);
+        updateCurrentMonitorAndRefreshVBlankDispatcher (ForceRefreshDispatcher::yes);
     }
 
     //==============================================================================
@@ -4625,6 +4657,7 @@ private:
 
     RectangleList<int> deferredRepaints;
     ScopedSuspendResumeNotificationRegistration suspendResumeRegistration;
+    std::optional<SimpleTimer> monitorUpdateTimer;
 
     //==============================================================================
     JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (HWNDComponentPeer)