[gnome-calculator] Set historyview pagesize based on scrolledwindow size request

[Robert Roth <robertroth src gnome org>]

commit 14945539bcde05740f20589e0747d2076b8fed3c
Author: Robert Roth <robert roth off gmail com>
Date:   Thu Oct 20 10:32:01 2016 +0300

    Set historyview pagesize based on scrolledwindow size request

 data/history-view.ui  |    2 +-
 src/math-history.vala |    4 +++-
 2 files changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/data/history-view.ui b/data/history-view.ui
index 0568f9f..0439f36 100644
--- a/data/history-view.ui
+++ b/data/history-view.ui
@@ -3,7 +3,7 @@
 <interface>
   <requires lib="gtk+" version="3.16"/>
   <template class="HistoryView" parent="GtkScrolledWindow">
-    <property name="height_request">114</property>
+    <property name="height_request">118</property>
     <property name="visible">True</property>
     <property name="can_focus">True</property>
     <property name="vexpand">True</property>
diff --git a/src/math-history.vala b/src/math-history.vala
index ed91b2f..b35d3d6 100644
--- a/src/math-history.vala
+++ b/src/math-history.vala
@@ -32,7 +32,9 @@ public class HistoryView : Gtk.ScrolledWindow
     {
         var adjustment = listbox.get_adjustment ();
         // TODO make this dynamic, do not hardcode listbox_height_request/number_of_rows
-        adjustment.page_size = 114 / 3;
+        int width, height;
+        get_size_request (out width, out height);
+        adjustment.page_size = height / 3;
         adjustment.set_value (adjustment.get_upper () - adjustment.get_page_size ());
     }