[gnome-games/wip/exalm/issue98: 4/4] collection-icon-view: Set children size via CSS

[Alexander Mikhaylenko <alexm src gnome org>]

commit 897a9369c16426d0b72db97d08eb61b75fa3618f
Author: Alexander Mikhaylenko <exalm7659 gmail com>
Date:   Sun Sep 23 14:47:53 2018 +0500

    collection-icon-view: Set children size via CSS
    
    Avoid manually setting width-request within size_allocate() handler.
    
    Use CSS 'min-width' property for sizing  and just dynamically add/remove a
    style class.

 data/gtk-style.css               |  8 ++++++++
 src/ui/collection-icon-view.vala | 27 ++-------------------------
 2 files changed, 10 insertions(+), 25 deletions(-)
---
diff --git a/data/gtk-style.css b/data/gtk-style.css
index bddbeb35..b3fab15b 100644
--- a/data/gtk-style.css
+++ b/data/gtk-style.css
@@ -26,6 +26,14 @@ gamesgamethumbnail {
        color: @theme_fg_color;
 }
 
+gamescollectioniconview flowboxchild {
+  min-width: 128px;
+}
+
+gamescollectioniconview.large flowboxchild {
+  min-width: 256px;
+}
+
 /* Styles from libhandy example, this should be kept in sync with this:
  * https://source.puri.sm/Librem5/libhandy/blob/master/examples/style.css
  */
diff --git a/src/ui/collection-icon-view.vala b/src/ui/collection-icon-view.vala
index 3290aee0..f5e7e0d4 100644
--- a/src/ui/collection-icon-view.vala
+++ b/src/ui/collection-icon-view.vala
@@ -78,9 +78,6 @@ private class Games.CollectionIconView : Gtk.Bin {
        [GtkChild]
        private GamepadBrowse gamepad_browse;
 
-       // Current size used by the thumbnails.
-       private int game_view_size;
-
        static construct {
                set_css_name ("gamescollectioniconview");
        }
@@ -215,7 +212,6 @@ private class Games.CollectionIconView : Gtk.Bin {
                var child = new Gtk.FlowBoxChild ();
 
                game_view.visible = true;
-               game_view.width_request = game_view_size;
                child.visible = true;
 
                child.add (game_view);
@@ -275,27 +271,8 @@ private class Games.CollectionIconView : Gtk.Bin {
                // them rather than a few huge thumbnails, making Games more usable on
                // small screens.
                if (allocation.width < 960)
-                       set_size (128);
+                       get_style_context ().remove_class ("large");
                else
-                       set_size (256);
-       }
-
-       private void set_size (int size) {
-               if (game_view_size == size)
-                       return;
-
-               game_view_size = size;
-
-               flow_box.forall ((child) => {
-                       var flow_box_child = child as Gtk.FlowBoxChild;
-
-                       assert (flow_box_child != null);
-
-                       var game_view = flow_box_child.get_child () as GameIconView;
-
-                       assert (game_view != null);
-
-                       game_view.width_request = size;
-               });
+                       get_style_context ().add_class ("large");
        }
 }