1 files changed, 22 insertions, 0 deletions
diff --git a/src/Fl_Gl_Window.cxx b/src/Fl_Gl_Window.cxx
index f3622508b..d77f15472 100644
--- a/src/Fl_Gl_Window.cxx
+++ b/src/Fl_Gl_Window.cxx
@@ -522,6 +522,28 @@ void Fl_Gl_Window::draw_overlay() {}
 void Fl_Gl_Window::draw() {
     Fl::fatal("Fl_Gl_Window::draw() *must* be overriden. Please refer to the documentation.");
 }
+
+
+/**
+ Handle some FLTK events as needed.
+ */
+int Fl_Gl_Window::handle(int event) 
+{
+#if (__APPLE_QUARTZ__)
+  if (event==FL_HIDE) {
+    // if we are not hidden, just the parent was hidden, so we must throw away the context
+    if (!visible_r())
+      context(0); // remove context wthout setting the hidden flags
+  }
+  if (event==FL_SHOW) {
+    // if we are not hidden, just the parent was shown, so we must create a new context
+    if (visible_r())
+      show(); //
+  }
+#endif
+  return Fl_Window::handle(event);
+}
+
 //
 // End of "$Id$".
 //