views: add focus ring to TreeView

ui/views/controls/tree/tree_view.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/views/controls/tree/tree_view.h"
 
 #include <algorithm>
 
 #include "base/i18n/rtl.h"
 #include "base/memory/ptr_util.h"
 #include "base/message_loop/message_loop.h"
 #include "ui/accessibility/ax_view_state.h"
 #include "ui/base/ime/input_method.h"
+#include "ui/base/material_design/material_design_controller.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/events/event.h"
 #include "ui/events/keycodes/keyboard_codes.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/rect_conversions.h"
 #include "ui/gfx/image/image.h"
 #include "ui/gfx/skia_util.h"
 #include "ui/native_theme/native_theme.h"
 #include "ui/resources/grit/ui_resources.h"
+#include "ui/views/controls/focus_ring.h"
 #include "ui/views/controls/prefix_selector.h"
 #include "ui/views/controls/scroll_view.h"
 #include "ui/views/controls/textfield/textfield.h"
 #include "ui/views/controls/tree/tree_view_controller.h"
 #include "ui/views/resources/grit/views_resources.h"
 #include "ui/views/style/platform_style.h"
 
 using ui::TreeModel;
 using ui::TreeModelNode;
 
@@ skipping 590 matching lines @@
 
 void TreeView::OnFocus() {
   if (GetInputMethod())
     GetInputMethod()->SetFocusedTextInputClient(GetPrefixSelector());
   View::OnFocus();
   SchedulePaintForNode(selected_node_);
 
   // Notify the InputMethod so that it knows to query the TextInputClient.
   if (GetInputMethod())
     GetInputMethod()->OnCaretBoundsChanged(GetPrefixSelector());
+
+  if (ui::MaterialDesignController::IsSecondaryUiMaterial() &&
+      PlatformStyle::kTreeViewHasFocusRing) {
+    ScrollView* focus_ring_view = FindFocusRingView();
+    focus_ring_view->SetHasFocusRing(true);
+    focus_ring_view->SchedulePaint();

[sky, 2016/10/12 23:58:01]

Are you sure you need a SchedulePaint here? If so, I think it should be in
ScrollView.

[Elly Fong-Jones, 2016/10/13 11:14:56]

I believe so - FocusRing::Install() and FocusRing::Uninstall() do it, anyway. I
moved it to ScrollView.

+  }
 }
 
 void TreeView::OnBlur() {
   if (GetInputMethod())
     GetInputMethod()->DetachTextInputClient(GetPrefixSelector());
   SchedulePaintForNode(selected_node_);
   if (selector_)
     selector_->OnViewBlur();
+  if (ui::MaterialDesignController::IsSecondaryUiMaterial() &&

[sky, 2016/10/12 23:58:01]

As this is nearly the same as the above and only differs in the parameter to
SetHasFocusRing, how about a function like SetShowFocusRing(bool)?

[Elly Fong-Jones, 2016/10/13 11:14:56]

Done.

+      PlatformStyle::kTreeViewHasFocusRing) {
+    ScrollView* focus_ring_view = FindFocusRingView();
+    focus_ring_view->SetHasFocusRing(false);
+    focus_ring_view->SchedulePaint();
+  }
 }
 
 bool TreeView::OnClickOrTap(const ui::LocatedEvent& event) {
   CommitEdit();
   RequestFocus();
 
   InternalNode* node = GetNodeAtPoint(event.location());
   if (!node)
     return true;
 
@@ skipping 398 matching lines @@
 
   int arrow_dx = depth * kIndent + kHorizontalInset;
   gfx::Rect arrow_bounds(bounds().x() + arrow_dx,
                          row * row_height_ + kVerticalInset, kArrowRegionSize,
                          row_height_);
   if (base::i18n::IsRTL())
     arrow_bounds.set_x(bounds().width() - arrow_dx - kArrowRegionSize);
   return arrow_bounds.Contains(point);
 }
 
+ScrollView* TreeView::FindFocusRingView() {
+  // If this View is the grandchild of a ScrollView, use the grandparent
+  // ScrollView for the focus ring instead of this View so that the focus ring
+  // won't be scrolled. Since ScrollViews have a single content view, which they
+  // wrap in a ScrollView::Viewport, being the grandchild of a ScrollView
+  // implies being the sole grandchild, which means it's fine to wrap the focus
+  // ring around the grandparent here.
+  View* grandparent = parent() ? parent()->parent() : nullptr;
+  if (grandparent && grandparent->GetClassName() == ScrollView::kViewClassName)
+    return static_cast<ScrollView*>(grandparent);
+  return nullptr;
+}
+
 // InternalNode ----------------------------------------------------------------
 
 TreeView::InternalNode::InternalNode()
     : model_node_(NULL),
       loaded_children_(false),
       is_expanded_(false),
       text_width_(0) {
 }
 
 TreeView::InternalNode::~InternalNode() {
@@ skipping 20 matching lines @@
   if (!is_expanded_)
     return max_width;
   for (int i = 0; i < child_count(); ++i) {
     max_width = std::max(max_width,
                          GetChild(i)->GetMaxWidth(indent, depth + 1));
   }
   return max_width;
 }
 
 }  // namespace views