AppInfoView: replace combobox with dropdown

data/styles/AppInfoView.scss

@@ -17,8 +17,12 @@ appinfoview {
             }
         }
 
-        combobox {
+        dropdown {
             margin-top: rem(12px);
+
+            button {
+                background-color: #{'@bg_color'};
+            }
         }
 
         button.text-button,

src/MainWindow.vala

@@ -366,7 +366,6 @@ public class AppCenter.MainWindow : Gtk.ApplicationWindow {
         }
 
         if (pk_child != null) {
-            pk_child.view_entered ();
             leaflet.visible_child = pk_child;
             return;
         }

src/Views/AppInfoView.vala

@@ -28,12 +28,12 @@ public class AppCenter.Views.AppInfoView : AppCenter.AbstractAppContainer {
 
     GenericArray<AppStream.Screenshot> screenshots;
 
+    private GLib.ListStore origin_liststore;
     private Granite.HeaderLabel whats_new_label;
     private Gtk.CssProvider accent_provider;
-    private Gtk.ComboBox origin_combo;
+    private Gtk.DropDown origin_dropdown;
     private Gtk.Label app_subtitle;
     private Gtk.ListBox extension_box;
-    private Gtk.ListStore origin_liststore;
     private Gtk.Overlay screenshot_overlay;
     private Gtk.Revealer origin_combo_revealer;
     private Adw.Carousel release_carousel;
@@ -144,21 +144,24 @@ public class AppCenter.Views.AppInfoView : AppCenter.AbstractAppContainer {
         app_subtitle.add_css_class (Granite.STYLE_CLASS_H3_LABEL);
         app_subtitle.add_css_class (Granite.STYLE_CLASS_DIM_LABEL);
 
-        origin_liststore = new Gtk.ListStore (2, typeof (AppCenterCore.Package), typeof (string));
-        origin_combo = new Gtk.ComboBox.with_model (origin_liststore) {
-            halign = Gtk.Align.START,
-            valign = Gtk.Align.CENTER
+        origin_liststore = new GLib.ListStore (typeof (AppCenterCore.Package));
+
+        var list_factory = new Gtk.SignalListItemFactory ();
+        list_factory.setup.connect (origin_setup_factory);
+        list_factory.bind.connect (origin_bind_factory);
+
+        origin_dropdown = new Gtk.DropDown (origin_liststore, null) {
+            halign = START,
+            valign = CENTER,
+            factory = list_factory
         };
 
         origin_combo_revealer = new Gtk.Revealer () {
-            child = origin_combo,
-            transition_type = Gtk.RevealerTransitionType.SLIDE_DOWN
+            child = origin_dropdown,
+            overflow = VISIBLE,
+            transition_type = SLIDE_DOWN
         };
 
-        var renderer = new Gtk.CellRendererText ();
-        origin_combo.pack_start (renderer, true);
-        origin_combo.add_attribute (renderer, "text", 1);
-
         var uninstall_button = new Gtk.Button.from_icon_name ("edit-delete-symbolic") {
             tooltip_text = _("Uninstall"),
             margin_end = 12
@@ -753,18 +756,14 @@ public class AppCenter.Views.AppInfoView : AppCenter.AbstractAppContainer {
             links_flowbox.append (share_button);
         }
 #endif
-        view_entered ();
         set_up_package ();
 
         if (oars_flowbox.get_first_child () != null) {
             oars_flowbox_revealer.reveal_child = true;
         }
 
-        origin_combo.changed.connect (() => {
-            Gtk.TreeIter iter;
-            AppCenterCore.Package selected_origin_package;
-            origin_combo.get_active_iter (out iter);
-            origin_liststore.@get (iter, 0, out selected_origin_package);
+        origin_dropdown.notify["selected-item"].connect (() => {
+            var selected_origin_package = (AppCenterCore.Package) origin_dropdown.selected_item;
             if (selected_origin_package != null && selected_origin_package != package) {
                 show_other_package (selected_origin_package, false, false);
             }
@@ -932,29 +931,14 @@ public class AppCenter.Views.AppInfoView : AppCenter.AbstractAppContainer {
         }
     }
 
-    public void view_entered () {
-        Gtk.TreeIter iter;
-        AppCenterCore.Package origin_package;
-        if (origin_liststore.get_iter_first (out iter)) {
-            do {
-                origin_liststore.@get (iter, 0, out origin_package);
-                if (origin_package == package) {
-                    origin_combo.set_active_iter (iter);
-                }
-            } while (origin_liststore.iter_next (ref iter));
-        }
-    }
-
     private void load_more_content () {
         var cache = AppCenterCore.Client.get_default ().screenshot_cache;
 
-        Gtk.TreeIter iter;
         uint count = 0;
         foreach (var origin_package in package.origin_packages) {
-            origin_liststore.append (out iter);
-            origin_liststore.set (iter, 0, origin_package, 1, origin_package.origin_description);
+            origin_liststore.append (origin_package);
             if (origin_package == package) {
-                origin_combo.set_active_iter (iter);
+                origin_dropdown.selected = count;
             }
 
             count++;
@@ -1219,6 +1203,24 @@ public class AppCenter.Views.AppInfoView : AppCenter.AbstractAppContainer {
         });
     }
 
+    private void origin_setup_factory (Object object) {
+        var title = new Gtk.Label ("") {
+            xalign = 0
+        };
+
+        var list_item = (Gtk.ListItem) object;
+        list_item.child = title;
+    }
+
+    private void origin_bind_factory (Object object) {
+        var list_item = object as Gtk.ListItem;
+
+        var package = (AppCenterCore.Package) list_item.get_item ();
+
+        var title = (Gtk.Label) list_item.child;
+        title.label = package.origin_description;
+    }
+
     class UrlButton : Gtk.Box {
         public UrlButton (string label, string? uri, string icon_name) {
             add_css_class (Granite.STYLE_CLASS_DIM_LABEL);