Bug 238854 [gtk2] Changing GNOME2 theme doesn't apply until restarting Mozilla

r=bryner, sr=dbaron, patch=ginn.chen@sun.com

gfx/src/gtk/nsDeviceContextGTK.cpp

@@ -672,15 +672,21 @@ int nsDeviceContextGTK::prefChanged(const char *aPref, void *aClosure)
 
     // If this pref changes, we have to clear our cache of stored system
     // fonts.
-    if (gSystemFonts) {
-      delete gSystemFonts;
-      gSystemFonts = nsnull;
-    }
+    ClearCachedSystemFonts();
   }
-  
+
   return 0;
 }
 
+void nsDeviceContextGTK::ClearCachedSystemFonts()
+{
+  //clear our cache of stored system fonts
+  if (gSystemFonts) {
+    delete gSystemFonts;
+    gSystemFonts = nsnull;
+  }
+}
+
 #define DEFAULT_TWIP_FONT_SIZE 240
 
 nsSystemFontsGTK::nsSystemFontsGTK(float aPixelsToTwips)

gfx/src/gtk/nsDeviceContextGTK.h

@@ -87,6 +87,7 @@ public:
   NS_IMETHOD GetDepth(PRUint32& aDepth);
 
   static int prefChanged(const char *aPref, void *aClosure);
+  static void ClearCachedSystemFonts();
 
 protected:
   nsresult   SetDPI(PRInt32 aPrefDPI);

gfx/src/gtk/nsNativeThemeGTK.cpp

@@ -39,6 +39,7 @@
 #include "nsNativeThemeGTK.h"
 #include "nsThemeConstants.h"
 #include "nsDrawingSurfaceGTK.h"
+#include "nsDeviceContextGTK.h"
 #include "gtkdrawing.h"
 
 #include "nsIObserverService.h"
@@ -644,6 +645,8 @@ nsNativeThemeGTK::WidgetStateChanged(nsIFrame* aFrame, PRUint8 aWidgetType,
 NS_IMETHODIMP
 nsNativeThemeGTK::ThemeChanged()
 {
+  nsDeviceContextGTK::ClearCachedSystemFonts();
+
   memset(mDisabledWidgetTypes, 0, sizeof(mDisabledWidgetTypes));
   return NS_OK;
 }

layout/base/nsPresContext.cpp

@@ -1146,9 +1146,12 @@ nsPresContext::ThemeChanged()
   // Clear all cached nsILookAndFeel colors.
   if (mLookAndFeel)
     mLookAndFeel->LookAndFeelChanged();
-  
-  if (mShell)
-    mShell->ReconstructStyleData();
+
+  // We have to clear style data because the assumption of style rule
+  // immutability has been violated since any style rule that uses
+  // system colors or fonts (and probably -moz-appearance as well) has
+  // changed.
+  nsPresContext::ClearStyleDataAndReflow();
 }
 
 void

layout/base/src/nsPresContext.cpp

@@ -1146,9 +1146,12 @@ nsPresContext::ThemeChanged()
   // Clear all cached nsILookAndFeel colors.
   if (mLookAndFeel)
     mLookAndFeel->LookAndFeelChanged();
-  
-  if (mShell)
-    mShell->ReconstructStyleData();
+
+  // We have to clear style data because the assumption of style rule
+  // immutability has been violated since any style rule that uses
+  // system colors or fonts (and probably -moz-appearance as well) has
+  // changed.
+  nsPresContext::ClearStyleDataAndReflow();
 }
 
 void

widget/src/gtk2/nsLookAndFeel.cpp

@@ -61,11 +61,7 @@ PRBool  nsLookAndFeel::sColorsInitialized = PR_FALSE;
 //-------------------------------------------------------------------------
 nsLookAndFeel::nsLookAndFeel() : nsXPLookAndFeel()
 {
-    mWidget = gtk_invisible_new();
-    gtk_object_ref(GTK_OBJECT(mWidget));
-    gtk_object_sink(GTK_OBJECT(mWidget));
-    gtk_widget_ensure_style(mWidget);
-    mStyle = gtk_widget_get_style(mWidget);
+    InitWidget();
 
     if (!sColorsInitialized)
         InitColors();
@@ -522,3 +518,27 @@ nsLookAndFeel::InitColors()
 
     gtk_widget_destroy(window);
 }
+
+void
+nsLookAndFeel::InitWidget()
+{
+    mWidget = gtk_invisible_new();
+    gtk_object_ref(GTK_OBJECT(mWidget));
+    gtk_object_sink(GTK_OBJECT(mWidget));
+    gtk_widget_ensure_style(mWidget);
+    mStyle = gtk_widget_get_style(mWidget);
+}
+
+NS_IMETHODIMP
+nsLookAndFeel::LookAndFeelChanged()
+{
+    nsXPLookAndFeel::LookAndFeelChanged();
+
+    if (mWidget)
+        gtk_widget_unref(mWidget);
+ 
+    InitWidget();
+    InitColors();
+
+    return NS_OK;
+}

widget/src/gtk2/nsLookAndFeel.h

@@ -51,6 +51,7 @@ public:
     nsresult NativeGetColor(const nsColorID aID, nscolor &aColor);
     NS_IMETHOD GetMetric(const nsMetricID aID, PRInt32 & aMetric);
     NS_IMETHOD GetMetric(const nsMetricFloatID aID, float & aMetric);
+    NS_IMETHOD LookAndFeelChanged();
 
 protected:
     GtkStyle *mStyle;
@@ -69,6 +70,7 @@ protected:
     static nscolor sButtonInnerDarkBorder;
 
     static void InitColors();
+    inline void InitWidget();
 };
 
 #endif

widget/src/gtk2/nsWindow.cpp

@@ -137,6 +137,9 @@ static gboolean window_state_event_cb     (GtkWidget *widget,
                                            GdkEventWindowState *event);
 static gboolean property_notify_event_cb  (GtkWidget *widget,
                                            GdkEventProperty *event);
+static void     style_set_cb              (GtkWidget *widget,
+                                           GtkStyle *previous_style,
+                                           gpointer data);
 #ifdef __cplusplus
 extern "C" {
 #endif /* __cplusplus */
@@ -1718,6 +1721,32 @@ nsWindow::OnWindowStateEvent(GtkWidget *aWidget, GdkEventWindowState *aEvent)
     DispatchEvent(&event, status);
 }
 
+void
+nsWindow::ThemeChanged()
+{
+    nsGUIEvent event(NS_THEMECHANGED, this);
+    nsEventStatus status = nsEventStatus_eIgnore;
+    DispatchEvent(&event, status);
+
+    if (!mDrawingarea)
+        return;
+
+    // Dispatch NS_THEMECHANGED to all child windows
+    GList *children = 
+        gdk_window_peek_children(mDrawingarea->inner_window);
+    while (children) {
+        GdkWindow *gdkWin = GDK_WINDOW(children->data);
+
+        nsWindow *win = (nsWindow*) g_object_get_data(G_OBJECT(gdkWin),
+                                                      "nsWindow");
+
+        if (win && win != this)   // guard against infinite recursion
+            win->ThemeChanged();
+
+        children = children->next;
+    }
+}
+
 gboolean
 nsWindow::OnDragMotionEvent(GtkWidget *aWidget,
                             GdkDragContext *aDragContext,
@@ -2216,6 +2245,8 @@ nsWindow::NativeCreate(nsIWidget        *aParent,
                          G_CALLBACK(window_state_event_cb), NULL);
         g_signal_connect(G_OBJECT(mShell), "property_notify_event",
                          G_CALLBACK(property_notify_event_cb), NULL);
+        g_signal_connect(G_OBJECT(mShell), "style_set",
+                         G_CALLBACK(style_set_cb), NULL);
     }
 
     if (mContainer) {
@@ -3720,6 +3751,15 @@ property_notify_event_cb  (GtkWidget *widget, GdkEventProperty *event)
     return FALSE;
 }
 
+/* static */
+void
+style_set_cb (GtkWidget *widget, GtkStyle *previous_style, gpointer data)
+{
+    nsWindow *window = get_window_for_gtk_widget(widget);
+    if (window)
+        window->ThemeChanged();
+}
+
 //////////////////////////////////////////////////////////////////////
 // These are all of our drag and drop operations
 

widget/src/gtk2/nsWindow.h

@@ -246,6 +246,8 @@ public:
     void               SetNonXEmbedPluginFocus(void);
     void               LoseNonXEmbedPluginFocus(void);
 
+    void               ThemeChanged(void);
+
     Window             mOldFocusWindow;
 
     static guint32     mLastButtonPressTime;