Add tiles to the experimental app list start page.

ui/app_list/views/tile_item_view.cc

+// Copyright 2014 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/tile_item_view.h"
+
+#include "base/strings/utf_string_conversions.h"
+#include "ui/app_list/app_list_constants.h"
+#include "ui/app_list/app_list_item.h"
+#include "ui/app_list/app_list_model.h"
+#include "ui/app_list/app_list_view_delegate.h"
+#include "ui/app_list/views/app_list_main_view.h"
+#include "ui/gfx/canvas.h"
+#include "ui/gfx/color_analysis.h"
+#include "ui/gfx/color_utils.h"
+#include "ui/views/background.h"
+#include "ui/views/controls/image_view.h"
+#include "ui/views/controls/label.h"
+#include "ui/views/layout/box_layout.h"
+
+namespace {
+
+const int kTileSize = 90;
+const SkColor kTileBackgroundColor = SK_ColorWHITE;
+const SkColor kTileBorderColor = SkColorSetARGB(0X30, 0xD0, 0xD0, 0xD0);

[tapted, 2014/05/22 04:56:11]

nit: the first 'x', in '0X30', should be lowercase

[calamity, 2014/05/27 04:29:11]

Done.

+const int kTileColorStripHeight = 2;
+const SkAlpha kTileColorStripOpacity = 0X5F;
+const int kTileCornerRadius = 2;
+
+// A background for the start page item view which consists of a rounded rect
+// with a dominant color strip at the bottom.
+class TileItemBackground : public views::Background {
+ public:
+  TileItemBackground() {}

[tapted, 2014/05/22 04:56:11]

initialize strip_color_?

[calamity, 2014/05/27 04:29:11]

Done.

+  virtual ~TileItemBackground() {}
+
+  void set_strip_color(SkColor strip_color) { strip_color_ = strip_color; }
+
+  // Overridden from views::Background:
+  virtual void Paint(gfx::Canvas* canvas, views::View* view) const OVERRIDE {
+    SkPaint paint;
+    paint.setFlags(SkPaint::kAntiAlias_Flag);
+
+    // Paint the border.
+    paint.setColor(kTileBorderColor);
+    canvas->DrawRoundRect(view->GetContentsBounds(), kTileCornerRadius, paint);
+
+    // Paint a rectangle for the color strip.
+    gfx::Rect color_strip_rect(view->GetContentsBounds());
+    color_strip_rect.Inset(1, 1, 1, 1);
+    paint.setColor(SkColorSetA(strip_color_, kTileColorStripOpacity));
+    canvas->DrawRoundRect(color_strip_rect, kTileCornerRadius, paint);
+
+    // Paint the main background rectangle, leaving part of the color strip
+    // unobscured.
+    gfx::Rect static_background_rect(color_strip_rect);
+    static_background_rect.Inset(0, 0, 0, kTileColorStripHeight);
+    paint.setColor(kTileBackgroundColor);
+    canvas->DrawRoundRect(static_background_rect, kTileCornerRadius, paint);
+  }
+
+ private:
+  SkColor strip_color_;
+
+  DISALLOW_COPY_AND_ASSIGN(TileItemBackground);
+};
+
+}  // namespace
+
+namespace app_list {
+
+TileItemView::TileItemView()
+    : views::CustomButton(this),
+      item_(NULL),
+      icon_(new views::ImageView),
+      title_(new views::Label),
+      background_(new TileItemBackground()) {
+  set_background(background_);
+
+  views::BoxLayout* layout_manager =
+      new views::BoxLayout(views::BoxLayout::kVertical, 10, 0, 0);

[tapted, 2014/05/22 04:56:11]

nit 10 -> some constant?
kSomethingGapSpacingSeparationMarginBorderPaddingPixels?

[calamity, 2014/05/27 04:29:11]

Done.

+  layout_manager->set_main_axis_alignment(
+      views::BoxLayout::MAIN_AXIS_ALIGNMENT_CENTER);
+  SetLayoutManager(layout_manager);
+
+  ui::ResourceBundle& rb = ui::ResourceBundle::GetSharedInstance();
+  title_->SetAutoColorReadabilityEnabled(false);
+  title_->SetEnabledColor(kGridTitleColor);
+  title_->SetFontList(rb.GetFontList(kItemTextFontStyle));
+  title_->SetHorizontalAlignment(gfx::ALIGN_CENTER);
+
+  AddChildView(icon_);
+  AddChildView(title_);
+}
+
+TileItemView::~TileItemView() {
+}
+
+void TileItemView::SetAppListItem(AppListItem* item) {
+  item_ = item;
+  if (!item) {
+    SetVisible(false);
+    icon_->SetImage(NULL);
+    title_->SetText(base::string16());
+    return;
+  }
+
+  SetVisible(true);
+  icon_->SetImage(item_->icon());

[tapted, 2014/05/22 04:56:11]

I think when an item is installing it's not guaranteed to be 48x48 -- see `void
AppListItemView::UpdateIcon()`. (maybe we should just fix that on the Chrome
side... but that's not how it's currently done).

[calamity, 2014/05/27 04:29:11]

Done.

+  title_->SetText(base::UTF8ToUTF16(item_->name()));
+
+  background_->set_strip_color(
+      color_utils::CalculateKMeanColorOfBitmap(*item_->icon().bitmap()));
+}

[tapted, 2014/05/22 04:56:11]

This will need to observe icon/title updates. Also, users might expect newly
installed apps to appear here. Those are probably fine for a follow-up.

However, a more dangerous one is that if one of these items is uninstalled I
think it will cause |item_| to become a destroyed pointer. And ButtonPressed(..)
to crash. Mayybe that's OK for now... But there might be an easy way to just
observe all changes and mash StartPageView::Reset(..) for the first cut.

There should be tests for all these operations on the model too

[calamity, 2014/05/27 04:29:11]

Done.

+
+gfx::Size TileItemView::GetPreferredSize() {
+  return gfx::Size(kTileSize, kTileSize);
+}
+
+void TileItemView::ButtonPressed(views::Button* sender,
+                                 const ui::Event& event) {
+  item_->Activate(event.flags());
+}
+
+}  // namespace app_list