aura: Implement app list M19 mock.

ash/app_list/app_list_model_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 "ash/app_list/app_list_model_view.h"
+
+#include "ash/app_list/app_list_item_view.h"
+#include "ash/app_list/app_list_model.h"
+#include "base/utf_string_conversions.h"
+#include "ui/views/controls/button/text_button.h"
+#include "ui/views/layout/grid_layout.h"
+
+namespace ash {
+
+namespace {
+
+// Minimum label width
+const int kMinLabelWidth = 150;
+
+// Calculate preferred tile size for given |content_size| and |num_of_tiles|.
+gfx::Size CalculateTileSize(const gfx::Size& content_size, int num_of_tiles) {
+  const int kIconSizes[] = { 64, 48, 32, 16 };
+
+  int tile_height = 0;
+  int tile_width = 0;
+  for (size_t i = 0; i < arraysize(kIconSizes); ++i) {
+    int icon_size = kIconSizes[i];
+    tile_height = icon_size + 2 * AppListItemView::kPadding;
+    tile_width = icon_size + std::min(kMinLabelWidth, icon_size * 2) +
+        2 * AppListItemView::kPadding;
+
+    int rows = content_size.height() / tile_height;
+    int cols = content_size.width() / tile_width;
+    if (rows * cols >= num_of_tiles)
+      break;
+  }
+
+  return gfx::Size(tile_width, tile_height);
+}
+
+}  // namespace
+
+AppListModelView::AppListModelView(views::ButtonListener* listener)
+    : model_(NULL),
+      listener_(listener) {
+}
+
+AppListModelView::~AppListModelView() {
+  if (model_)
+    model_->RemoveObserver(this);
+}
+
+void AppListModelView::SetModel(AppListModel* model) {
+  DCHECK(model);
+
+  if (model_)
+    model_->RemoveObserver(this);
+
+  model_ = model;
+  model_->AddObserver(this);
+  Update();
+}
+
+void AppListModelView::Update() {
+  RemoveAllChildViews(true);
+  if (!model_ || model_->item_count() == 0)
+    return;
+
+  for (int i = 0; i < model_->item_count(); ++i)
+    AddChildView(new AppListItemView(model_->GetItem(i), listener_));
+
+  Layout();
+  SchedulePaint();
+}
+
+void AppListModelView::Layout() {
+  gfx::Rect rect(GetContentsBounds());
+
+  gfx::Size tile_size = CalculateTileSize(rect.size(), child_count());
+
+  int col_bottom = rect.bottom();
+  gfx::Rect current_tile(rect.origin(), tile_size);
+
+  for (int i = 0; i < child_count(); ++i) {
+    views::View* view = child_at(i);
+    view->SetBoundsRect(current_tile);
+
+    current_tile.Offset(0, tile_size.height());

[sky, 2012/03/01 00:26:57]

Do we really want to tile vertically instead of horizontally?

[xiyuan, 2012/03/01 19:58:47]

Yes. The mock lists all items vertically in columns.

+    if (current_tile.bottom() >= col_bottom) {
+      current_tile.set_x(current_tile.x() + tile_size.width());
+      current_tile.set_y(rect.y());
+    }
+  }
+}
+
+void AppListModelView::ListItemsAdded(int start, int count) {
+  Update();
+}
+
+void AppListModelView::ListItemsRemoved(int start, int count) {
+  Update();
+}
+
+void AppListModelView::ListItemsChanged(int start, int count) {
+  NOTREACHED();
+}
+
+}  // namespace ash