Add basic grouing features.

Adds simple opener-based grouping to the experimental tab controller.

Clicks are not handled for activation. Tabs are rendered overlapped
properly.

Bug: 778461
Change-Id: Ic93cb109875d815018a6197e35b10b358959ac02
Reviewed-on: https://chromium-review.googlesource.com/777735Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Brett Wilson <brettw@chromium.org>
Cr-Commit-Position: refs/heads/master@{#517913}

chrome/browser/ui/tabs/tab_data_experimental.cc

@@ -58,10 +58,11 @@ TabDataExperimental::~TabDataExperimental() = default;
 TabDataExperimental& TabDataExperimental::operator=(TabDataExperimental&&) =
     default;
 
-const base::string16& TabDataExperimental::GetTitle() const {
-  DCHECK(type() == Type::kSingle);
+base::string16 TabDataExperimental::GetTitle() const {
   // TODO(brettw) this will need to use TabUIHelper.
-  return contents_->GetTitle();
+  if (contents_)
+    return contents_->GetTitle();
+  return base::string16();
 }
 
 bool TabDataExperimental::CountsAsViewIndex() const {

chrome/browser/ui/tabs/tab_data_experimental.h

@@ -49,12 +49,13 @@ class TabDataExperimental {
   TabDataExperimental* parent() { return parent_; }
 
   Type type() const { return type_; }
+  void set_type(Type t) { type_ = t; }
+
   bool expanded() const { return expanded_; }
 
   content::WebContents* contents() { return contents_; }
 
-  // Valid when type() == kSingle or kHubAndSpoke.
-  const base::string16& GetTitle() const;
+  base::string16 GetTitle() const;
 
   // Returns true if this tab data itself is counted as a enumerable item when
   // going through the view.

chrome/browser/ui/tabs/tab_strip_model_experimental.cc

@@ -379,12 +379,30 @@ void TabStripModelExperimental::InsertWebContentsAt(
   delegate_->WillAddWebContents(contents);
 
   bool active = (add_types & ADD_ACTIVE) != 0;
+  TabDataExperimental* data = nullptr;
+
+  if ((add_types & ADD_INHERIT_GROUP) && active_index() >= 0 &&
+      active_index() < count()) {
+    // Add as a child following opener.
+    TabDataExperimental* parent = GetDataForViewIndex(active_index());
+    if (parent->type() == TabDataExperimental::Type::kSingle) {
+      // Promote parent to hub-and-spoke.
+      parent->set_type(TabDataExperimental::Type::kHubAndSpoke);
+      for (auto& observer : exp_observers_)
+        observer.TabChanged(parent);
+    }
+
+    parent->children_.push_back(std::make_unique<TabDataExperimental>(
+        parent, TabDataExperimental::Type::kSingle, contents, this));
+    data = parent->children_.back().get();
+
+  } else {
+    // Add at toplevel.
+    tabs_.push_back(std::make_unique<TabDataExperimental>(
+        nullptr, TabDataExperimental::Type::kSingle, contents, this));
+    data = tabs_.back().get();
+  }
 
-  // Always insert tabs at the end for now (so parent is always null).
-  TabDataExperimental* parent = nullptr;
-  tabs_.emplace_back(std::make_unique<TabDataExperimental>(
-      parent, TabDataExperimental::Type::kSingle, contents, this));
-  const TabDataExperimental* data = tabs_.back().get();
   UpdateViewCount();
   index = tab_view_count_ - 1;
 
@@ -407,7 +425,6 @@ bool TabStripModelExperimental::CloseWebContentsAt(int view_index,
                                                    uint32_t close_types) {
   ViewIterator found = FindViewIndex(view_index);
   DCHECK(found != end());
-  DCHECK(found->type() == TabDataExperimental::Type::kSingle);
   content::WebContents* closing = found->contents_;
   if (closing)
     InternalCloseTabs(base::span<content::WebContents*>(&closing, 1));
@@ -527,8 +544,21 @@ TabDataExperimental* TabStripModelExperimental::GetDataForViewIndex(
   return &*found;
 }
 
+int TabStripModelExperimental::GetViewIndexForData(
+    const TabDataExperimental* data) const {
+  int view_index = 0;
+  for (const auto& cur : *this) {
+    if (&cur == data)
+      return view_index;
+    ++view_index;
+  }
+  return kNoTab;
+}
+
 void TabStripModelExperimental::ActivateTabAt(int index, bool user_gesture) {
-  DCHECK(ContainsIndex(index));
+  if (!ContainsIndex(index))
+    return;
+
   ui::ListSelectionModel new_model = selection_model_;
   new_model.SetSelectedIndex(index);
   SetSelection(std::move(new_model),
@@ -649,7 +679,6 @@ bool TabStripModelExperimental::IsTabPinned(int index) const {
 }
 
 bool TabStripModelExperimental::IsTabBlocked(int index) const {
-  NOTIMPLEMENTED();
   return false;
 }
 
@@ -689,6 +718,10 @@ void TabStripModelExperimental::AddWebContents(content::WebContents* contents,
                                                int index,
                                                ui::PageTransition transition,
                                                int add_types) {
+  // Force group inheritance for link click transitions.
+  if (ui::PageTransitionTypeIncludingQualifiersIs(transition,
+                                                  ui::PAGE_TRANSITION_LINK))
+    add_types |= ADD_INHERIT_GROUP;
   InsertWebContentsAt(index, contents, add_types);
 }
 
@@ -769,6 +802,7 @@ void TabStripModelExperimental::DetachWebContents(
     NOTREACHED();  // WebContents not found in this model.
     return;
   }
+  TabDataExperimental* data = &*found;
 
   bool was_selected;
   if (view_index == kNoTab)
@@ -777,12 +811,31 @@ void TabStripModelExperimental::DetachWebContents(
     was_selected = IsTabSelected(view_index);
   int next_selected_index = view_index;
 
-  if (found->parent_) {
-    // Erase in parent.
-    found->parent_->children_.erase(found->parent_->children_.begin() +
-                                    found.inner_index_);
+  if (data->parent_) {
+    TabDataExperimental* parent = data->parent_;
+    // Erase out of the parent.
+    parent->children_.erase(parent->children_.begin() + found.inner_index_);
+
+    if (parent->children_.empty()) {
+      if (parent->type() == TabDataExperimental::Type::kHubAndSpoke) {
+        // Erasing the last child of a hub and spoke one converts it back to
+        // a single.
+        parent->set_type(TabDataExperimental::Type::kSingle);
+        for (auto& observer : exp_observers_)
+          observer.TabChanged(parent);
+      } else {
+        DCHECK(parent->type() == TabDataExperimental::Type::kGroup);
+        // TODO(brettw) remove group. Notifications might be tricky.
+      }
+    }
+  } else if (data->type() == TabDataExperimental::Type::kHubAndSpoke) {
+    // Removing the "hub" from a hub and spoke converts to a group.
 
-    // TODO(brettw) remove the parent if it's empty!
+    data->set_type(TabDataExperimental::Type::kGroup);
+    data->contents_ =
+        nullptr;  // TODO(brettw) does this delete things properly?
+    for (auto& observer : exp_observers_)
+      observer.TabChanged(data);
   } else {
     // Just remove from tabs.
     tabs_.erase(tabs_.begin() + found.toplevel_index_);

chrome/browser/ui/tabs/tab_strip_model_experimental.h

@@ -196,6 +196,9 @@ class TabStripModelExperimental : public TabStripModel {
   const TabDataExperimental* GetDataForViewIndex(int view_index) const;
   TabDataExperimental* GetDataForViewIndex(int view_index);
 
+  // Returns kNoTab if there isn't a view index for this data.
+  int GetViewIndexForData(const TabDataExperimental* data) const;
+
   void AddExperimentalObserver(TabStripModelExperimentalObserver* observer);
   void RemoveExperimentalObserver(TabStripModelExperimentalObserver* observer);
 

chrome/browser/ui/views/tabs/tab.cc

@@ -264,8 +264,7 @@ class Tab::TabCloseButton : public views::ImageButton,
   explicit TabCloseButton(Tab* tab)
       : views::ImageButton(tab),
         tab_(tab) {
-    SetEventTargeter(
-        std::unique_ptr<views::ViewTargeter>(new views::ViewTargeter(this)));
+    SetEventTargeter(std::make_unique<views::ViewTargeter>(this));
   }
 
   ~TabCloseButton() override {}
@@ -461,8 +460,7 @@ Tab::Tab(TabController* controller, gfx::AnimationContainer* container)
   title_->SetText(CoreTabHelper::GetDefaultTitle());
   AddChildView(title_);
 
-  SetEventTargeter(
-      std::unique_ptr<views::ViewTargeter>(new views::ViewTargeter(this)));
+  SetEventTargeter(std::make_unique<views::ViewTargeter>(this));
 
   throbber_ = new ThrobberView(this);
   throbber_->SetVisible(false);

chrome/browser/ui/views/tabs/tab_experimental.cc

@@ -6,11 +6,13 @@
 
 #include "chrome/browser/ui/layout_constants.h"
 #include "chrome/browser/ui/tab_contents/core_tab_helper.h"
-#include "chrome/browser/ui/tabs/tab_data_experimental.h"
+#include "chrome/browser/ui/tabs/tab_strip_model_experimental.h"
 #include "chrome/browser/ui/view_ids.h"
 #include "components/grit/components_scaled_resources.h"
 #include "ui/views/border.h"
 #include "ui/views/controls/label.h"
+#include "ui/views/masked_targeter_delegate.h"
+#include "ui/views/widget/widget.h"
 
 namespace {
 
@@ -27,9 +29,12 @@ float GetTabEndcapWidth() {
 
 }  // namespace
 
-TabExperimental::TabExperimental(const TabDataExperimental* data)
+TabExperimental::TabExperimental(TabStripModelExperimental* model,
+                                 const TabDataExperimental* data)
     : views::View(),
+      model_(model),
       data_(data),
+      type_(data->type()),
       title_(new views::Label),
       hover_controller_(this),
       paint_(this) {
@@ -40,6 +45,8 @@ TabExperimental::TabExperimental(const TabDataExperimental* data)
   title_->SetText(CoreTabHelper::GetDefaultTitle());
   AddChildView(title_);
 
+  SetEventTargeter(std::make_unique<views::ViewTargeter>(this));
+
   // So we get don't get enter/exit on children and don't prematurely stop the
   // hover.
   set_notify_enter_exit_on_child(true);
@@ -73,23 +80,84 @@ void TabExperimental::SetSelected(bool selected) {
 }
 
 void TabExperimental::DataUpdated() {
+  type_ = data_->type();
   title_->SetText(data_->GetTitle());
 }
 
+void TabExperimental::SetGroupLayoutParams(int first_child_begin_x) {
+  first_child_begin_x_ = first_child_begin_x;
+}
+
 int TabExperimental::GetOverlap() {
   // We want to overlap the endcap portions entirely.
   return gfx::ToCeiledInt(GetTabEndcapWidth());
 }
 
+bool TabExperimental::GetHitTestMask(gfx::Path* mask) const {
+  // When the window is maximized we don't want to shave off the edges or top
+  // shadow of the tab, such that the user can click anywhere along the top
+  // edge of the screen to select a tab. Ditto for immersive fullscreen.
+  const views::Widget* widget = GetWidget();
+  *mask = paint_.GetBorderPath(
+      GetWidget()->GetCompositor()->device_scale_factor(), true,
+      widget && (widget->IsMaximized() || widget->IsFullscreen()),
+      GetTabEndcapWidth(), size());
+  return true;
+}
+
 void TabExperimental::OnPaint(gfx::Canvas* canvas) {
-  paint_.PaintTabBackground(canvas, active_, 0, 0, nullptr);
+  if (type_ == TabDataExperimental::Type::kSingle)
+    paint_.PaintTabBackground(canvas, active_, 0, 0, nullptr);
+  else
+    paint_.PaintGroupBackground(canvas, active_);
 }
 
 void TabExperimental::Layout() {
+  // Space between the favicon and title.
   constexpr int kTitleSpacing = 6;
   const gfx::Rect bounds = GetContentsBounds();
 
-  title_->SetBoundsRect(gfx::Rect(bounds.x() + kTitleSpacing, bounds.y(),
-                                  bounds.width() - (kTitleSpacing * 2),
-                                  bounds.height()));
+  int title_left = bounds.x() + kTitleSpacing;
+  int title_right;
+  if (first_child_begin_x_ >= 0)
+    title_right = first_child_begin_x_;
+  else
+    title_right = bounds.width() - kTitleSpacing;
+
+  title_->SetBoundsRect(gfx::Rect(title_left, bounds.y(),
+                                  title_right - title_left, bounds.height()));
+}
+
+bool TabExperimental::OnMousePressed(const ui::MouseEvent& event) {
+  // TODO(brettw) the non-experimental one has some stuff about touch and
+  // multi-selection here.
+  if (event.IsOnlyLeftMouseButton())
+    model_->ActivateTabAt(model_->GetViewIndexForData(data_), true);
+  return true;
+}
+
+void TabExperimental::OnMouseReleased(const ui::MouseEvent& event) {
+  // Close tab on middle click, but only if the button is released over the tab
+  // (normal windows behavior is to discard presses of a UI element where the
+  // releases happen off the element).
+  if (event.IsMiddleMouseButton()) {
+    if (HitTestPoint(event.location())) {
+      // TODO(brettw) old one did PrepareForCloseAt which does some animation
+      // stuff.
+      model_->CloseWebContentsAt(
+          model_->GetViewIndexForData(data_),
+          TabStripModel::CLOSE_USER_GESTURE |
+              TabStripModel::CLOSE_CREATE_HISTORICAL_TAB);
+    } else if (closing_) {
+      // We're animating closed and a middle mouse button was pushed on us but
+      // we don't contain the mouse anymore. We assume the user is clicking
+      // quicker than the animation and we should close the tab that falls under
+      // the mouse.
+      /* TODO(brettw) fast closing.
+      Tab* closest_tab = controller_->GetTabAt(this, event.location());
+      if (closest_tab)
+        controller_->CloseTab(closest_tab, CLOSE_TAB_FROM_MOUSE);
+      */
+    }
+  }
 }

chrome/browser/ui/views/tabs/tab_experimental.h

@@ -6,24 +6,33 @@
 #define CHROME_BROWSER_UI_VIEWS_TABS_TAB_EXPERIMENTAL_H_
 
 #include "base/macros.h"
+#include "chrome/browser/ui/tabs/tab_data_experimental.h"
 #include "chrome/browser/ui/views/tabs/tab_experimental_paint.h"
 #include "ui/views/controls/glow_hover_controller.h"
+#include "ui/views/masked_targeter_delegate.h"
 #include "ui/views/view.h"
 
 class TabDataExperimental;
+class TabStripModelExperimental;
 
 namespace views {
 class Label;
 }
 
-class TabExperimental : public views::View {
+class TabExperimental : public views::MaskedTargeterDelegate,
+                        public views::View {
  public:
-  explicit TabExperimental(const TabDataExperimental* data);
+  explicit TabExperimental(TabStripModelExperimental* model,
+                           const TabDataExperimental* data);
   ~TabExperimental() override;
 
   // Will be null when closing.
   const TabDataExperimental* data() const { return data_; }
 
+  // Cached stuff from data_ that can be used regardless of whether the data
+  // pointer is null or not.
+  TabDataExperimental::Type type() const { return type_; }
+
   // The view order is stored on a tab for the use of TabStrip layout and
   // computatations. It is not used directly by this class. It represents this
   // tab's position in the current layout.
@@ -52,17 +61,30 @@ class TabExperimental : public views::View {
   // to redraw everything.
   void DataUpdated();
 
+  // Called for group types when layout is done to set the bounds of the
+  // first tab. This is used to determine some painting parameters.
+  void SetGroupLayoutParams(int first_child_begin_x);
+
   // Returns the overlap between adjacent tabs.
   static int GetOverlap();
 
  private:
+  // views::MaskedTargeterDelegate:
+  bool GetHitTestMask(gfx::Path* mask) const override;
+
   // views::View:
   void OnPaint(gfx::Canvas* canvas) override;
   void Layout() override;
+  bool OnMousePressed(const ui::MouseEvent& event) override;
+  void OnMouseReleased(const ui::MouseEvent& event) override;
+
+  TabStripModelExperimental* model_;
 
   // Will be null when closing.
   const TabDataExperimental* data_;
 
+  TabDataExperimental::Type type_;
+
   size_t view_order_ = static_cast<size_t>(-1);
   gfx::Rect ideal_bounds_;
 
@@ -72,6 +94,9 @@ class TabExperimental : public views::View {
 
   views::Label* title_;  // Non-owning (owned by View hierarchy).
 
+  // Location of the first child tab. Negative indicates unused.
+  int first_child_begin_x_ = -1;
+
   views::GlowHoverController hover_controller_;
 
   TabExperimentalPaint paint_;

chrome/browser/ui/views/tabs/tab_experimental_paint.h

@@ -26,12 +26,26 @@ class TabExperimentalPaint {
   explicit TabExperimentalPaint(views::View* view);
   ~TabExperimentalPaint();
 
+  // Returns a path corresponding to the tab's outer border for a given tab
+  // |size|, |scale|, and |endcap_width|. If |unscale_at_end| is true, this
+  // path will be normalized to a 1x scale by scaling by 1/scale before
+  // returning. If |extend_to_top| is true, the path is extended vertically to
+  // the top of the tab bounds.  The caller uses this for Fitts' Law purposes
+  // in maximized/fullscreen mode.
+  gfx::Path GetBorderPath(float scale,
+                          bool unscale_at_end,
+                          bool extend_to_top,
+                          float endcap_width,
+                          const gfx::Size& size) const;
+
   void PaintTabBackground(gfx::Canvas* canvas,
                           bool active,
                           int fill_id,
                           int y_offset,
                           gfx::Path* clip);
 
+  void PaintGroupBackground(gfx::Canvas* canvas, bool active);
+
  private:
   class BackgroundCache {
    public:

chrome/browser/ui/views/tabs/tab_strip_experimental.h

@@ -11,6 +11,7 @@
 #include "base/compiler_specific.h"
 #include "base/containers/flat_map.h"
 #include "base/containers/flat_set.h"
+#include "base/containers/span.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
@@ -423,6 +424,12 @@ class TabStripExperimental : public TabStrip,
   // Ensures that view_order_ corresponds to the latest tabs_ structure.
   void EnsureViewOrderUpToDate() const;
 
+  // Recursive backend for EnsureViewOrderUpToDate.
+  void ComputeViewOrder(
+      base::span<const std::unique_ptr<TabDataExperimental>> tabs,
+      const TabDataExperimental* selected,
+      std::vector<TabExperimental*>* output) const;
+
   // -- Member Variables ------------------------------------------------------
 
   TabStripModelExperimental* model_;
@@ -437,8 +444,9 @@ class TabStripExperimental : public TabStrip,
   // this will cause them to be painted in order of their memory address!
   base::flat_set<TabExperimental*> closing_tabs_;
 
-  // Cached ordered vector for painting the tabs. This will include everything
-  // in the tabs_ map and also the items in closing_tabs_.
+  // Cached ordered vector for painting the tabs. The topmost view is at the
+  // front(). This will include everything in the tabs_ map and also the items
+  // in closing_tabs_.
   //
   // This is computed by EnsureViewOrderUpToDate().
   mutable std::vector<TabExperimental*> view_order_;

chrome/browser/ui/views/tabs/tab_strip_impl.cc

@@ -1934,10 +1934,10 @@ void TabStripImpl::SetTabBoundsForDrag(
 
 void TabStripImpl::AddMessageLoopObserver() {
   if (!mouse_watcher_.get()) {
-    mouse_watcher_.reset(new views::MouseWatcher(
+    mouse_watcher_ = std::make_unique<views::MouseWatcher>(
         new views::MouseWatcherViewHost(
             this, gfx::Insets(0, 0, kTabStripAnimationVSlop, 0)),
-        this));
+        this);
   }
   mouse_watcher_->Start();
 }