[PATCH] Fix a few gtk3 deprecation warnings in dialog_mapped()

[Nikolas Nyby]

---
 gtkwindows.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/gtkwindows.c b/gtkwindows.c
index 353e594d..2803627d 100644
--- a/gtkwindows.c
+++ b/gtkwindows.c
@@ -104,10 +104,23 @@ dialog_mapped(GtkWidget * window, gpointer UNUSED(data))
 {
     GdkRectangle monitorrect;
     GtkAllocation allocation;
-    GdkScreen *screen = gtk_widget_get_screen(window);
 
     gtk_widget_get_allocation(window, &allocation);
 
+#if GTK_CHECK_VERSION(3,0,0)
+    GdkDisplay *display = gtk_widget_get_display(window);
+    if (!display || gdk_display_get_n_monitors(display) == 1) {
+        monitorrect.x = 0;
+        monitorrect.y = 0;
+        monitorrect.width = gdk_screen_width();
+        monitorrect.height = gdk_screen_height();
+    } else {
+        GdkMonitor *monitor = gdk_display_get_monitor_at_window(display,
+                                                                
gtk_widget_get_window(window));
+        gdk_monitor_get_geometry(monitor, &monitorrect);
+    }
+#else
+    GdkScreen *screen = gtk_widget_get_screen(window);
     if (!screen || gdk_screen_get_n_monitors(screen) == 1) {
         monitorrect.x = 0;
         monitorrect.y = 0;
@@ -117,6 +130,7 @@ dialog_mapped(GtkWidget * window, gpointer UNUSED(data))
         int monitor = gdk_screen_get_monitor_at_window(screen, 
gtk_widget_get_window(window));
         gdk_screen_get_monitor_geometry(screen, monitor, &monitorrect);
     }
+#endif
 
     if (allocation.width > monitorrect.width || allocation.height > 
monitorrect.height) {       /* Dialog bigger than window! (just show at top 
left) */
         gtk_window_move(GTK_WINDOW(window), monitorrect.x, monitorrect.y);
-- 
2.34.1