[gnome-sudoku/arnaudb/wip/gtk4] Restore Start screen spirit.

[Arnaud B. <arnaudb src gnome org>]

commit 5db37c5e56f44e5bfaac1b143d51d89ee445096e
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Thu Sep 24 18:35:23 2020 +0200

    Restore Start screen spirit.

 data/gnome-sudoku.css | 4 ++++
 data/gnome-sudoku.ui  | 4 +++-
 src/gnome-sudoku.vala | 6 ++++++
 src/sudoku-view.vala  | 5 -----
 4 files changed, 13 insertions(+), 6 deletions(-)
---
diff --git a/data/gnome-sudoku.css b/data/gnome-sudoku.css
index 93bf22e..deb73c9 100644
--- a/data/gnome-sudoku.css
+++ b/data/gnome-sudoku.css
@@ -5,3 +5,7 @@ grid.board {
 grid.block {
   background: #999;
 }
+
+.top-separator {
+  border-top: 1px solid @borders;
+}
diff --git a/data/gnome-sudoku.ui b/data/gnome-sudoku.ui
index 770bde3..ab65154 100644
--- a/data/gnome-sudoku.ui
+++ b/data/gnome-sudoku.ui
@@ -151,7 +151,6 @@
                       <object class="GtkFrame">
                         <child>
                           <object class="GtkListBox">
-                            <property name="show-separators">True</property>
                             <property name="can-focus">False</property>
                             <child>
                               <object class="GtkListBoxRow">
@@ -220,6 +219,9 @@
                                     <property name="use-underline">True</property>
                                   </object>
                                 </property>
+                                <style>
+                                  <class name="top-separator"/>
+                                </style>
                               </object>
                             </child>
                           </object>
diff --git a/src/gnome-sudoku.vala b/src/gnome-sudoku.vala
index 36cb8c7..f2cc416 100644
--- a/src/gnome-sudoku.vala
+++ b/src/gnome-sudoku.vala
@@ -149,6 +149,12 @@ public class Sudoku : Gtk.Application
 
         Window.set_default_icon_name ("org.gnome.Sudoku");
 
+        var css_provider = new CssProvider ();
+        css_provider.load_from_resource ("/org/gnome/Sudoku/ui/gnome-sudoku.css");
+        Gdk.Display? gdk_display = Gdk.Display.get_default ();
+        if (gdk_display != null) // else..?
+            StyleContext.add_provider_for_display ((!) gdk_display, css_provider, 
STYLE_PROVIDER_PRIORITY_APPLICATION);
+
         var builder = new Builder.from_resource ("/org/gnome/Sudoku/ui/gnome-sudoku.ui");
 
         window = (ApplicationWindow) builder.get_object ("sudoku_app");
diff --git a/src/sudoku-view.vala b/src/sudoku-view.vala
index b87e29e..fa621c3 100644
--- a/src/sudoku-view.vala
+++ b/src/sudoku-view.vala
@@ -558,16 +558,12 @@ public class SudokuView : Widget
                 drawing.hide ();
         });
 
-        var css_provider = new CssProvider ();
-        css_provider.load_from_resource ("/org/gnome/Sudoku/ui/gnome-sudoku.css");
-
         grid = new Grid ();
         grid.row_spacing = 2;
         grid.column_spacing = 2;
         grid.column_homogeneous = true;
         grid.row_homogeneous = true;
         grid.get_style_context ().add_class ("board");
-        grid.get_style_context ().add_provider (css_provider, Gtk.STYLE_PROVIDER_PRIORITY_APPLICATION);
 
         var blocks = new Grid[game.board.block_rows, game.board.block_cols];
         for (var block_row = 0; block_row < game.board.block_rows; block_row++)
@@ -580,7 +576,6 @@ public class SudokuView : Widget
                 block_grid.column_homogeneous = true;
                 block_grid.row_homogeneous = true;
                 block_grid.get_style_context ().add_class ("block");
-                block_grid.get_style_context ().add_provider (css_provider, 
Gtk.STYLE_PROVIDER_PRIORITY_APPLICATION);
                 grid.attach (block_grid, block_col, block_row, 1, 1);
 
                 blocks[block_row, block_col] = block_grid;