Use ink drop hover for focus states on toolbar buttons and location

ui/views/controls/button/md_text_button.cc

 // Copyright 2015 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/button/md_text_button.h"
 
 #include "base/i18n/case_conversion.h"
 #include "ui/base/material_design/material_design_controller.h"
+#include "ui/gfx/canvas.h"
 #include "ui/gfx/color_utils.h"
 #include "ui/native_theme/native_theme.h"
 #include "ui/views/background.h"
 #include "ui/views/border.h"
 #include "ui/views/controls/button/blue_button.h"
 #include "ui/views/painter.h"
 
 namespace views {
 
 namespace {
 
+// The amount to enlarge the focus border in all directions relative to the
+// button.
+const int kFocusBorderOutset = -2;
+
+// The corner radius of the focus border roundrect.
+const int kFocusBorderCornerRadius = 3;
+
+class MdFocusRing : public views::View {
+ public:
+  MdFocusRing() {
+    SetPaintToLayer(true);
+    layer()->SetFillsBoundsOpaquely(false);
+  }
+  ~MdFocusRing() override {}
+
+  bool CanProcessEventsWithinSubtree() const override { return false; }
+
+  void OnPaint(gfx::Canvas* canvas) override {
+    MdTextButton::PaintMdFocusRing(canvas, this);
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(MdFocusRing);
+};
+
 // Inset between clickable region border and button contents (text).
 const int kHorizontalPadding = 12;
 const int kVerticalPadding = 6;
 
 // Minimum size to reserve for the button contents.
 const int kMinWidth = 48;
 
 LabelButton* CreateButton(ButtonListener* listener,
                           const base::string16& text,
                           bool md) {
@@ skipping 41 matching lines @@
   button->SetText(text);
   // TODO(estade): can we get rid of the platform style border hoopla if
   // we apply the MD treatment to all buttons, even GTK buttons?
   button->SetBorder(
       Border::CreateEmptyBorder(kVerticalPadding, kHorizontalPadding,
                                 kVerticalPadding, kHorizontalPadding));
   button->SetFocusForPlatform();
   return button;
 }
 
+// static
+void MdTextButton::PaintMdFocusRing(gfx::Canvas* canvas, views::View* view) {
+  SkPaint paint;
+  paint.setAntiAlias(true);
+  paint.setColor(view->GetNativeTheme()->GetSystemColor(
+      ui::NativeTheme::kColorId_CallToActionColor));
+  paint.setStyle(SkPaint::kStroke_Style);
+  paint.setStrokeWidth(1);
+  gfx::RectF rect(view->GetLocalBounds());
+  rect.Inset(gfx::InsetsF(0.5));
+  canvas->DrawRoundRect(rect, kFocusBorderCornerRadius, paint);
+}
+
 void MdTextButton::SetCallToAction(CallToAction cta) {
   if (cta_ == cta)
     return;
 
   cta_ = cta;
   UpdateColorsFromNativeTheme();
 }
 
+void MdTextButton::Layout() {

[sky, 2016/05/26 21:13:01]

Don't you need to call LabelButton::Layout ?

[Evan Stade, 2016/05/26 22:26:30]

oops, yes.

+  gfx::Rect focus_bounds = GetLocalBounds();
+  focus_bounds.Inset(gfx::Insets(kFocusBorderOutset));
+  focus_ring_->SetBoundsRect(focus_bounds);
+}
+
+void MdTextButton::OnFocus() {
+  LabelButton::OnFocus();
+  focus_ring_->SetVisible(true);
+}
+
+void MdTextButton::OnBlur() {
+  LabelButton::OnBlur();
+  focus_ring_->SetVisible(false);
+}
+
 void MdTextButton::OnNativeThemeChanged(const ui::NativeTheme* theme) {
   LabelButton::OnNativeThemeChanged(theme);
   UpdateColorsFromNativeTheme();
 }
 
 SkColor MdTextButton::GetInkDropBaseColor() const {
   return color_utils::DeriveDefaultIconColor(label()->enabled_color());
 }
 
+bool MdTextButton::ShouldShowInkDropForFocus() const {
+  // These types of button use |focus_ring_|.
+  return false;
+}
+
 void MdTextButton::SetText(const base::string16& text) {
   LabelButton::SetText(base::i18n::ToUpper(text));
 }
 
 void MdTextButton::UpdateStyleToIndicateDefaultStatus() {
   // Update the call to action state to reflect defaultness. Don't change strong
   // call to action to weak.
   if (!is_default())
     SetCallToAction(NO_CALL_TO_ACTION);
   else if (cta_ == NO_CALL_TO_ACTION)
     SetCallToAction(WEAK_CALL_TO_ACTION);
 }
 
 MdTextButton::MdTextButton(ButtonListener* listener)
     : LabelButton(listener, base::string16()),
-      ink_drop_delegate_(this, this),
+      focus_ring_(new MdFocusRing()),
       cta_(NO_CALL_TO_ACTION) {
-  set_ink_drop_delegate(&ink_drop_delegate_);
+  set_ink_drop_delegate(
+      base::WrapUnique(new ButtonInkDropDelegate(this, this)));
   set_has_ink_drop_action_on_click(true);
   SetHorizontalAlignment(gfx::ALIGN_CENTER);
   SetFocusForPlatform();
   SetMinSize(gfx::Size(kMinWidth, 0));
   SetFocusPainter(nullptr);
-  UseMdFocusRing();
   label()->SetAutoColorReadabilityEnabled(false);
+
+  AddChildView(focus_ring_);
+  focus_ring_->SetVisible(false);
+  set_request_focus_on_press(false);

[sky, 2016/05/26 21:13:01]

Do any places using MdTextButton and expecting true need to be updated?

[Evan Stade, 2016/05/26 22:26:30]

I don't think so. This was already being done by virtue of UseMdFocusRing()
calling set_request_focus_on_press(false);

 }
 
 MdTextButton::~MdTextButton() {}
 
 void MdTextButton::UpdateColorsFromNativeTheme() {
   ui::NativeTheme::ColorId fg_color_id = ui::NativeTheme::kColorId_NumColors;
   switch (cta_) {
     case NO_CALL_TO_ACTION:
       // When there's no call to action, respect a color override if one has
       // been set. For other call to action states, don't let individual buttons
@@ skipping 16 matching lines @@
       cta_ == STRONG_CALL_TO_ACTION
           ? Background::CreateBackgroundPainter(
                 true, Painter::CreateSolidRoundRectPainter(
                           theme->GetSystemColor(
                               ui::NativeTheme::kColorId_CallToActionColor),
                           kInkDropSmallCornerRadius))
           : nullptr);
 }
 
 }  // namespace views