Support glib 2.73.1+: Avoid property notification during object construction

What Happened?

In elementary/calendar#756 (comment), we noticed that wingpanel-indicator-datetime does not show any date numbers, after making a minimal reproducer in https://github.com/bobby285271/e-calendar-issue and bisecting glib commits (thanks @jtojnar!), we noticed that this glib commit intentionally changes the behavior, which is part of glib 2.73.1+. It will be nice to adjust the code here so the indicator can still work nicely with glib 2.73.1+.

The affected code is at

wingpanel-indicator-datetime/src/Widgets/calendar/GridDay.vala

Lines 82 to 85 in 2bd9445

    
           notify["date"].connect (() => { 
        
               label.label = date.get_day_of_month ().to_string (); 
        
           });

The workaround is

diff --git a/src/Widgets/calendar/Grid.vala b/src/Widgets/calendar/Grid.vala
index e440306..21a631a 100644
--- a/src/Widgets/calendar/Grid.vala
+++ b/src/Widgets/calendar/Grid.vala
@@ -229,7 +229,7 @@ namespace DateTime.Widgets {
                 day.sensitive_container (false);
             }
 
-            day.date = new_date;
+            day.update_date (new_date);
 
             return day;
         }
diff --git a/src/Widgets/calendar/GridDay.vala b/src/Widgets/calendar/GridDay.vala
index 8602875..7bd6140 100644
--- a/src/Widgets/calendar/GridDay.vala
+++ b/src/Widgets/calendar/GridDay.vala
@@ -79,10 +79,6 @@ public class DateTime.Widgets.GridDay : Gtk.EventBox {
         button_press_event.connect (on_button_press);
         key_press_event.connect (on_key_press);
 
-        notify["date"].connect (() => {
-            label.label = date.get_day_of_month ().to_string ();
-        });
-
         component_dots = new Gee.HashMap<string, Gtk.Widget> ();
     }
 
@@ -124,6 +120,11 @@ public class DateTime.Widgets.GridDay : Gtk.EventBox {
         }
     }
 
+    public void update_date (GLib.DateTime date) {
+        this.date = date;
+        label.label = date.get_day_of_month ().to_string ();
+    }
+
     public void set_selected (bool selected) {
         if (selected) {
             set_state_flags (Gtk.StateFlags.SELECTED, true);

/cc elementary/calendar#761

Steps to Reproduce

Build with glib 2.73.1+
Notice the indicator does not show any date numbers

Thanks for the patch @bobby285271. I’ll try to build an MR around that after checking that it effectively fix the thing on my side too.

	notify["date"].connect (() => {
	label.label = date.get_day_of_month ().to_string ();
	});