[ash-md] Makes Wi-Fi header row sticky when network list is scrolled

ash/common/system/chromeos/network/network_list_md.cc

Index: ash/common/system/chromeos/network/network_list_md.cc
diff --git a/ash/common/system/chromeos/network/network_list_md.cc b/ash/common/system/chromeos/network/network_list_md.cc
index c5a5bfbb4cdda6c4bfd8d277d733274f08e20412..c64d573e8f31ace2287a8b9587f7413df207630f 100644
--- a/ash/common/system/chromeos/network/network_list_md.cc
+++ b/ash/common/system/chromeos/network/network_list_md.cc
@@ -10,7 +10,10 @@
 #include "ash/common/system/chromeos/network/network_icon_animation.h"
 #include "ash/common/system/chromeos/network/network_info.h"
 #include "ash/common/system/chromeos/network/network_list_delegate.h"
+#include "ash/common/system/tray/header_list_scroll_view.h"
+#include "ash/common/system/tray/tray_constants.h"
 #include "base/memory/ptr_util.h"
+#include "base/strings/utf_string_conversions.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/power_manager/power_supply_properties.pb.h"
 #include "chromeos/dbus/power_manager_client.h"
@@ -27,6 +30,7 @@
 #include "ui/gfx/font.h"
 #include "ui/gfx/paint_vector_icon.h"
 #include "ui/gfx/vector_icons_public.h"
+#include "ui/views/background.h"
 #include "ui/views/border.h"
 #include "ui/views/controls/button/image_button.h"
 #include "ui/views/controls/button/toggle_button.h"
@@ -46,16 +50,14 @@ namespace ash {
 
 namespace {
 
+const int kWiFiGroupId = 1;
 const int kWiFiButtonSize = 48;
 const int kWifiRowVerticalInset = 4;
 const int kWifiRowLeftInset = 18;
 const int kWifiRowRightInset = 14;
-const int kWifiRowSeparatorThickness = 1;
 const int kWifiRowChildSpacing = 14;
 const int kFocusBorderInset = 1;
 
-const SkColor kWifiRowSeparatorColor = SkColorSetA(SK_ColorBLACK, 0x1F);
-
 bool IsProhibitedByPolicy(const chromeos::NetworkState* network) {
   if (!NetworkTypePattern::WiFi().MatchesType(network->type()))
     return false;
@@ -116,11 +118,12 @@ class NetworkListViewMd::WifiHeaderRowView : public views::View {
     return GetPreferredSize().height();
   }
 
+  const char* GetClassName() const override { return "WifiHeaderRowView"; }
+
  private:
   void Init() {
+    set_background(views::Background::CreateSolidBackground(kBackgroundColor));
     // TODO(tdanderson): Need to unify this with the generic menu row class.
-    SetBorder(views::Border::CreateSolidSidedBorder(
-        kWifiRowSeparatorThickness, 0, 0, 0, kWifiRowSeparatorColor));
     views::View* container = new views::View;
     container->SetBorder(views::Border::CreateEmptyBorder(
         0, kWifiRowLeftInset, 0, kWifiRowRightInset));
@@ -377,6 +380,7 @@ NetworkListViewMd::UpdateNetworkListEntries() {
         handler->IsTechnologyEnabled(NetworkTypePattern::WiFi()), index,
         &wifi_header_view_);
     ++index;
+    wifi_header_view_->SetGroup(kWiFiGroupId);
 
     // "Wifi Enabled / Disabled".
     int message_id = 0;
@@ -388,6 +392,8 @@ NetworkListViewMd::UpdateNetworkListEntries() {
     UpdateInfoLabel(message_id, index, &no_wifi_networks_view_);
     if (message_id)
       ++index;
+    if (no_wifi_networks_view_)
+      no_wifi_networks_view_->SetGroup(kWiFiGroupId);
 
     // Add Wi-Fi networks.
     std::unique_ptr<std::set<std::string>> new_wifi_service_paths =
@@ -409,6 +415,7 @@ NetworkListViewMd::UpdateNetworkListEntries() {
 std::unique_ptr<std::set<std::string>> NetworkListViewMd::UpdateNetworkChildren(
     bool is_wifi,
     int index) {
+  int group_id = is_wifi ? kWiFiGroupId : -1;
   std::unique_ptr<std::set<std::string>> new_service_paths(
       new std::set<std::string>);
   for (const auto& info : network_list_) {
@@ -416,6 +423,17 @@ std::unique_ptr<std::set<std::string>> NetworkListViewMd::UpdateNetworkChildren(
       continue;
     UpdateNetworkChild(index++, info.get());
     new_service_paths->insert(info->service_path);
+
+    // TODO(varkha) Demo code - remove before committing!
+    views::View* network_view = service_path_map_[info->service_path];
+    if (info->label == base::UTF8ToUTF16("wifi12") ||
+        info->label == base::UTF8ToUTF16("wifi15") ||
+        info->label == base::UTF8ToUTF16("wifi20")) {
+      network_view->set_background(
+          views::Background::CreateSolidBackground(kBackgroundColor));
+      ++group_id;
+    }
+    network_view->SetGroup(group_id);
   }
   return new_service_paths;
 }
@@ -433,16 +451,23 @@ void NetworkListViewMd::UpdateNetworkChild(int index, const NetworkInfo* info) {
     network_view->Layout();
     network_view->SchedulePaint();
   }
-  PlaceViewAtIndex(network_view, index);
+  bool is_header = (info->label == base::UTF8ToUTF16("wifi12") ||
+                    info->label == base::UTF8ToUTF16("wifi15") ||
+                    info->label == base::UTF8ToUTF16("wifi20"));
+  PlaceViewAtIndex(network_view, index, is_header);
   if (info->disable)
     network_view->SetEnabled(false);
   network_map_[network_view] = info->service_path;
   service_path_map_[info->service_path] = network_view;
 }
 
-void NetworkListViewMd::PlaceViewAtIndex(views::View* view, int index) {
+void NetworkListViewMd::PlaceViewAtIndex(views::View* view,
+                                         int index,
+                                         bool is_header) {
   if (view->parent() != container()) {
     container()->AddChildViewAt(view, index);
+    if (is_header)
+      container()->SetHeaderView(view);
   } else {
     if (container()->child_at(index) == view)
       return;
@@ -468,7 +493,7 @@ void NetworkListViewMd::UpdateInfoLabel(int message_id,
   if (!label)
     label = delegate_->CreateInfoLabel();
   label->SetText(text);
-  PlaceViewAtIndex(label, insertion_index);
+  PlaceViewAtIndex(label, insertion_index, false /* is_header */);
   *label_ptr = label;
 }
 
@@ -478,7 +503,7 @@ void NetworkListViewMd::UpdateWifiHeaderRow(bool enabled,
   if (!*view)
     *view = new WifiHeaderRowView(this, enabled);
   (*view)->SetWifiEnabled(enabled);
-  PlaceViewAtIndex(*view, child_index);
+  PlaceViewAtIndex(*view, child_index, true /* is_header */);
 }
 
 void NetworkListViewMd::NetworkIconChanged() {