[gnome-usage] graph-stack-switcher: Change graphSwitcherButton to GtkRadioButton

[Felipe Borges <felipeborges src gnome org>]

commit f44dc4b1eed2a08457702e2ca5dc85e99e2c0c11
Author: Petr Štětka <pstetka redhat com>
Date:   Mon Jan 15 15:49:06 2018 +0100

    graph-stack-switcher: Change graphSwitcherButton to GtkRadioButton
    
    With GtkRadioButton we can benefit from its "grouping" capabilities
    to make sure that only one is active/toggled at the time.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=785801

 data/interface/adwaita.css     | 16 +------------
 src/graph-stack-switcher.vala  | 53 ++++++++++++++----------------------------
 src/graph-switcher-button.vala | 17 +++++++++++---
 3 files changed, 33 insertions(+), 53 deletions(-)
---
diff --git a/data/interface/adwaita.css b/data/interface/adwaita.css
index 2bd261c..7a75efa 100644
--- a/data/interface/adwaita.css
+++ b/data/interface/adwaita.css
@@ -46,25 +46,11 @@ subprocess-list row.max:hover {
     border: 1px solid #faa5a2;
 }
 
-graph-switcher-button {
-    padding: 6px 10px;
+button.graph-switcher {
     border-style: none;
     border-radius: 0;
 }
 
-graph-switcher-button:hover {
-    background-color: @theme_base_color;
-}
-
-graph-switcher-button:checked {
-    background-color: alpha(@theme_fg_color, 0.2);
-}
-
-graph-switcher-button:active {
-    background-color: alpha(@theme_fg_color, 0.2);
-    box-shadow: inset 0 2px 2px -2px rgba(0, 0, 0, 0.2);
-}
-
 rg-graph.big {
     background-color: #ffffff;
     background-size: 57px 57px;
diff --git a/src/graph-stack-switcher.vala b/src/graph-stack-switcher.vala
index b3845c5..f13a02c 100644
--- a/src/graph-stack-switcher.vala
+++ b/src/graph-stack-switcher.vala
@@ -25,9 +25,7 @@ namespace Usage
         Gtk.Stack stack;
         View[] sub_views;
 
-        Gtk.ToggleButton[] buttons;
-
-        bool can_change = true;
+        GraphSwitcherButton[] buttons;
 
                public GraphStackSwitcher(Gtk.Stack stack, View[] sub_views)
                {
@@ -41,44 +39,29 @@ namespace Usage
                 new GraphSwitcherButton.memory(_("Memory"))
             };
 
-           foreach(Gtk.ToggleButton button in buttons)
+            foreach(GraphSwitcherButton button in buttons)
             {
                 this.pack_start(button, false, true, 0);
-            }
-
-           buttons[0].set_active (true);
 
-            foreach(Gtk.ToggleButton button in buttons)
-            {
-                button.toggled.connect (() => {
-                    if(can_change)
-                    {
-                        if (button.active)
-                        {
-                            can_change = false;
-
-                            int i = 0;
-                            int button_number = 0;
-                            foreach(Gtk.ToggleButton btn in buttons)
-                            {
-                                if(btn != button)
-                                    btn.active = false;
-                                else
-                                    button_number = i;
-                                i++;
-                            }
-                            this.stack.set_visible_child_name(this.sub_views[button_number].name);
+                button.button_release_event.connect(() => {
+                    var button_number = get_button_number(button);
+                    this.stack.set_visible_child_name(this.sub_views[button_number].name);
 
-                            can_change = true;
-                        } else
-                        {
-                            can_change = false;
-                            button.active = true;
-                            can_change = true;
-                        }
-                    }
+                    return false;
                 });
             }
         }
+
+        private int get_button_number(Gtk.Button button)
+        {
+            for(int i = 0; i < buttons.length; i++)
+            {
+                if(buttons[i] == button)
+                    return i;
+            }
+
+            return 0;
+        }
+
     }
 }
diff --git a/src/graph-switcher-button.vala b/src/graph-switcher-button.vala
index c42e1c0..452dc93 100644
--- a/src/graph-switcher-button.vala
+++ b/src/graph-switcher-button.vala
@@ -20,8 +20,10 @@
 
 namespace Usage
 {
-    public class GraphSwitcherButton : Gtk.ToggleButton
+    public class GraphSwitcherButton : Gtk.RadioButton
     {
+        private static Gtk.RadioButton? _group = null;
+
         public GraphSwitcherButton.processor(string label)
         {
             Rg.Graph processor_graph = new CpuGraphMostUsed();
@@ -54,9 +56,18 @@ namespace Usage
             return box;
         }
 
-        class construct
+        construct
         {
-            set_css_name("graph-switcher-button");
+            if(_group == null)
+                _group = this;
+            else
+                join_group(_group);
+
+            set_mode(false);
+
+            var context = get_style_context();
+            context.add_class("flat");
+            context.add_class("graph-switcher");
         }
     }
 }