Allow Uber Tray popup pointing to the related tray item view.

ash/system/tray/system_tray.cc

Index: ash/system/tray/system_tray.cc
diff --git a/ash/system/tray/system_tray.cc b/ash/system/tray/system_tray.cc
index e0362d57e60cfc0db3328e544eb3cb1a1a91bbc0..24098b4b6dc5238341832c3ae0aa041c9660ccd1 100644
--- a/ash/system/tray/system_tray.cc
+++ b/ash/system/tray/system_tray.cc
@@ -243,6 +243,7 @@ void SystemTray::AddTrayItem(SystemTrayItem* item) {
   if (tray_item) {
     tray_container_->AddChildViewAt(tray_item, 0);
     PreferredSizeChanged();
+    tray_item_map_[item] = tray_item;
   }
 }
 
@@ -251,7 +252,11 @@ void SystemTray::RemoveTrayItem(SystemTrayItem* item) {
 }
 
 void SystemTray::ShowDefaultView() {
-  ShowItems(items_.get(), false, true);
+  ShowDefaultViewWithOffset(-1);
+}
+
+void SystemTray::ShowDefaultViewWithOffset(int arrow_offset) {

[sadrul, 2012/05/15 02:18:15]

The order of the functions in the .cc file should match the order in the .h file

[Jun Mukai, 2012/05/15 02:43:05]

Done.

+  ShowItems(items_.get(), false, true, arrow_offset);
 }
 
 void SystemTray::ShowDetailedView(SystemTrayItem* item,
@@ -259,7 +264,7 @@ void SystemTray::ShowDetailedView(SystemTrayItem* item,
                                   bool activate) {
   std::vector<SystemTrayItem*> items;
   items.push_back(item);
-  ShowItems(items, true, activate);
+  ShowItems(items, true, activate, GetTrayXOffset(item));
   bubble_->StartAutoCloseTimer(close_delay);
 }
 
@@ -334,9 +339,40 @@ void SystemTray::SetPaintsBackground(
   hide_background_animator_.SetPaintsBackground(value, change_type);
 }
 
+int SystemTray::GetTrayXOffset(SystemTrayItem* item) const {
+  std::map<SystemTrayItem*, views::View*>::const_iterator it =
+      tray_item_map_.find(item);
+  if (it == tray_item_map_.end())
+    return -1;
+
+  const views::View* item_view = it->second;
+  gfx::Rect item_bounds = item_view->bounds();
+  if (!item_bounds.IsEmpty()) {
+    int x_offset = item_bounds.x() + item_bounds.width() / 2;
+    return base::i18n::IsRTL() ? x_offset : tray_container_->width() - x_offset;
+  }
+
+  // Sometimes the bounds of item is still empty.  In that case, we
+  // want to guess the offset from the position of its parent.

[sadrul, 2012/05/15 02:18:15]

I guess this happens when the tray-view for an item is invisible (e.g. for
caps-lock when it's turned off)?

[Jun Mukai, 2012/05/15 02:43:05]

No... It happens first time the user presses caps lock.  At that time, the view
bounds is not yet calculated, so the bounds is (0, 0), 0x0.
Added the comment more to describe this situation.

[sadrul, 2012/05/15 02:58:16]

Ah, cool. Thanks for explaining.

+  int x_offset = 0;
+  for (int i = 0; i < tray_container_->child_count(); ++i) {
+    const views::View* child = tray_container_->child_at(i);
+    if (child == item_view)
+      return base::i18n::IsRTL() ?
+          x_offset : tray_container_->width() - x_offset;
+
+    if (!child->visible())
+      continue;
+    x_offset = child->bounds().right();
+  }
+
+  return -1;
+}
+
 void SystemTray::ShowItems(const std::vector<SystemTrayItem*>& items,
                            bool detailed,
-                           bool can_activate) {
+                           bool can_activate,
+                           int arrow_offset) {
   // Destroy any existing bubble and create a new one.
   SystemTrayBubble::BubbleType bubble_type = detailed ?
       SystemTrayBubble::BUBBLE_TYPE_DETAILED :
@@ -345,8 +381,12 @@ void SystemTray::ShowItems(const std::vector<SystemTrayItem*>& items,
   ash::SystemTrayDelegate* delegate =
       ash::Shell::GetInstance()->tray_delegate();
   views::View* anchor = tray_container_;
-  bubble_->InitView(anchor, SystemTrayBubble::ANCHOR_TYPE_TRAY,
-                    can_activate, delegate->GetUserLoginStatus());
+  SystemTrayBubble::InitParams init_params(SystemTrayBubble::ANCHOR_TYPE_TRAY);
+  init_params.anchor = anchor;
+  init_params.can_activate = can_activate;
+  init_params.login_status = delegate->GetUserLoginStatus();
+  init_params.arrow_offset = arrow_offset;
+  bubble_->InitView(init_params);
   // If we have focus the shelf should be visible and we need to continue
   // showing the shelf when the popup is shown.
   if (GetWidget()->IsActive())
@@ -375,10 +415,12 @@ void SystemTray::UpdateNotificationBubble() {
     anchor = tray_container_;
     anchor_type = SystemTrayBubble::ANCHOR_TYPE_TRAY;
   }
-  notification_bubble_->InitView(
-      anchor, anchor_type,
-      false /* can_activate */,
-      ash::Shell::GetInstance()->tray_delegate()->GetUserLoginStatus());
+  SystemTrayBubble::InitParams init_params(anchor_type);
+  init_params.anchor = anchor;
+  init_params.login_status =
+      ash::Shell::GetInstance()->tray_delegate()->GetUserLoginStatus();
+  init_params.arrow_offset = GetTrayXOffset(notification_items_[0]);
+  notification_bubble_->InitView(init_params);
 }
 
 void SystemTray::UpdateNotificationAnchor() {
@@ -396,7 +438,14 @@ bool SystemTray::PerformAction(const views::Event& event) {
       bubble_->bubble_type() == SystemTrayBubble::BUBBLE_TYPE_DEFAULT) {
     bubble_->Close();
   } else {
-    ShowDefaultView();
+    int arrow_offset = -1;
+    if (event.IsMouseEvent() || event.IsTouchEvent()) {
+      const views::LocatedEvent& located_event =
+          static_cast<const views::LocatedEvent&>(event);
+      arrow_offset = base::i18n::IsRTL() ?
+          located_event.x() : tray_container_->width() - located_event.x();
+    }
+    ShowDefaultViewWithOffset(arrow_offset);
   }
   return true;
 }