cros: add SUGGESTED APPS indicator to start page

ui/app_list/views/indicator_chip_view.cc

+// Copyright 2017 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/app_list/views/indicator_chip_view.h"
+
+#include "ui/base/resource/resource_bundle.h"
+#include "ui/gfx/canvas.h"
+#include "ui/views/background.h"
+#include "ui/views/border.h"
+#include "ui/views/controls/label.h"
+#include "ui/views/layout/fill_layout.h"
+
+namespace app_list {
+
+namespace {
+
+constexpr int kIndicatorHeight = 16;
+constexpr int kHorizontalPadding = 16;
+constexpr int kBorderCornerRadius = 8;
+
+constexpr SkColor kLabelColor = SkColorSetARGBMacro(0x8A, 0xFF, 0xFF, 0xFF);
+constexpr SkColor kBackgroundColor =
+    SkColorSetARGBMacro(0x14, 0xFF, 0xFF, 0xFF);
+
+class IndicatorBackground : public views::Background {
+ public:
+  IndicatorBackground() = default;
+  ~IndicatorBackground() override = default;
+
+ private:
+  // views::Background overrides:
+  void Paint(gfx::Canvas* canvas, views::View* view) const override {
+    cc::PaintFlags flags;
+    flags.setStyle(cc::PaintFlags::kFill_Style);
+    flags.setColor(kBackgroundColor);
+    flags.setAntiAlias(true);
+    canvas->DrawRoundRect(view->GetContentsBounds(), kBorderCornerRadius,
+                          flags);
+  }
+
+  DISALLOW_COPY_AND_ASSIGN(IndicatorBackground);
+};
+
+}  // namespace
+
+IndicatorChipView::IndicatorChipView(base::string16 text) {
+  container_ = new views::View();
+  container_->set_can_process_events_within_subtree(false);
+  AddChildView(container_);
+
+  container_->SetBackground(base::MakeUnique<IndicatorBackground>());
+
+  label_ = new views::Label(text);
+  gfx::FontList small_font =

[xiyuan, 2017/06/22 22:33:51]

gfx::FontList -> const gfx::FontList&

[Qiang(Joe) Xu, 2017/06/22 22:47:26]

Done.

+      ui::ResourceBundle::GetSharedInstance().GetFontList(
+          ui::ResourceBundle::SmallFont);
+  label_->SetFontList(small_font.DeriveWithSizeDelta(-2));
+  label_->SetBorder(views::NullBorder());

[xiyuan, 2017/06/22 22:33:52]

border is null by default. We probably can remove this.

[Qiang(Joe) Xu, 2017/06/22 22:47:27]

Done.

+  label_->SetEnabledColor(kLabelColor);
+  label_->SetAutoColorReadabilityEnabled(false);
+  label_->SetBackgroundColor(SK_ColorTRANSPARENT);

[xiyuan, 2017/06/22 22:33:52]

Try to avoid SK_ColorTRANSPARENT background. Font anti-alias and hinting might
not work properly on a transparent background. If |label_| is always inside
|container_|, we can use kBackgroundColor for label background.

[Qiang(Joe) Xu, 2017/06/22 22:47:26]

acknowledged, done

+  label_->SetHandlesTooltips(false);
+  label_->SetHorizontalAlignment(gfx::ALIGN_CENTER);
+
+  container_->AddChildView(label_);
+}
+
+IndicatorChipView::~IndicatorChipView() = default;
+
+gfx::Size IndicatorChipView::CalculatePreferredSize() const {
+  const int label_width = label_->GetPreferredSize().width();
+  return gfx::Size(
+      label_width + 2 * kHorizontalPadding + 2 * kBorderCornerRadius,
+      kIndicatorHeight);
+}
+
+void IndicatorChipView::Layout() {
+  const int label_width = label_->GetPreferredSize().width();
+  container_->SetSize(
+      gfx::Size(label_width + 2 * kHorizontalPadding, kIndicatorHeight));
+  label_->SetBoundsRect(container_->GetContentsBounds());
+}
+
+}  // namespace app_list