[gtksourceview] gutter: fix line number drawing upon resize

[Christian Hergert <chergert src gnome org>]

commit 8911a7ae879c078583d6a65df221f1dd5add62fb
Author: Christian Hergert <chergert redhat com>
Date:   Thu Feb 11 14:41:12 2021 -0800

    gutter: fix line number drawing upon resize
    
    This fixes an issue where the line numbers were not updated until we
    hovered over the gutter.
    
    Fixes #170

 gtksourceview/gtksourcegutter.c | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)
---
diff --git a/gtksourceview/gtksourcegutter.c b/gtksourceview/gtksourcegutter.c
index ca282477..889a7b2e 100644
--- a/gtksourceview/gtksourcegutter.c
+++ b/gtksourceview/gtksourcegutter.c
@@ -79,6 +79,7 @@ struct _GtkSourceGutter
        GtkOrientation        orientation;
 
        gulong                adj_changed_handler;
+       gulong                adj_upper_changed_handler;
 
        guint                 is_drawing : 1;
 };
@@ -190,14 +191,15 @@ static void
 on_adjustment_value_changed (GtkAdjustment   *adj,
                              GtkSourceGutter *gutter)
 {
-       const GList *list;
-
-       for (list = gutter->renderers; list; list = list->next)
-       {
-               Renderer *renderer = list->data;
+       _gtk_source_gutter_queue_draw (gutter);
+}
 
-               gtk_widget_queue_draw (GTK_WIDGET (renderer->renderer));
-       }
+static void
+on_adjustment_upper_changed (GtkAdjustment   *adj,
+                             GParamSpec      *pspec,
+                             GtkSourceGutter *gutter)
+{
+       _gtk_source_gutter_queue_draw (gutter);
 }
 
 static GtkAdjustment *
@@ -227,6 +229,11 @@ connect_view (GtkSourceGutter *gutter,
                                  "value-changed",
                                  G_CALLBACK (on_adjustment_value_changed),
                                  gutter);
+       gutter->adj_upper_changed_handler =
+               g_signal_connect (get_adjustment (gutter, view),
+                                 "notify::upper",
+                                 G_CALLBACK (on_adjustment_upper_changed),
+                                 gutter);
 }
 
 static void
@@ -238,6 +245,8 @@ disconnect_view (GtkSourceGutter *gutter,
 
        g_clear_signal_handler (&gutter->adj_changed_handler,
                                get_adjustment (gutter, view));
+       g_clear_signal_handler (&gutter->adj_upper_changed_handler,
+                               get_adjustment (gutter, view));
 }
 
 static void
@@ -1018,7 +1027,7 @@ _gtk_source_gutter_queue_draw (GtkSourceGutter *gutter)
        {
                Renderer *renderer = iter->data;
 
-               gtk_widget_queue_allocate (GTK_WIDGET (renderer->renderer));
+               gtk_widget_queue_draw (GTK_WIDGET (renderer->renderer));
        }
 }