AppList Performance Optimization 2

ui/app_list/views/start_page_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/start_page_view.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/i18n/rtl.h"
@@ skipping 184 matching lines @@
 
   // Update the tile item results.
   for (size_t i = 0; i < search_result_tile_views_.size(); ++i) {
     SearchResult* item = nullptr;
     if (i < display_results.size())
       item = display_results[i];
     search_result_tile_views_[i]->SetSearchResult(item);
     search_result_tile_views_[i]->SetEnabled(true);
   }
 
-  Layout();
   parent()->Layout();
   // Add 1 to the results size to account for the all apps button.
   return display_results.size() + 1;
 }
 
 void StartPageView::StartPageTilesContainer::UpdateSelectedIndex(
     int old_selected,
     int new_selected) {
   if (old_selected >= 0 && old_selected < num_results())
     GetTileItemView(old_selected)->SetSelected(false);
@@ skipping 26 matching lines @@
   views::ColumnSet* column_set = tiles_layout_manager->AddColumnSet(0);
   column_set->AddPaddingColumn(0, kTilesHorizontalMarginLeft);
   for (int col = 0; col < kNumStartPageTilesCols; ++col) {
     column_set->AddColumn(views::GridLayout::FILL, views::GridLayout::FILL, 0,
                           views::GridLayout::USE_PREF, 0, 0);
     column_set->AddPaddingColumn(0, kTileSpacing);
   }
 
   // Add SearchResultTileItemViews to the container.
   int i = 0;
+  search_result_tile_views_.reserve(apps_num);
   for (; i < apps_num; ++i) {
     SearchResultTileItemView* tile_item =
         new SearchResultTileItemView(this, view_delegate_);
     if (i % kNumStartPageTilesCols == 0)
       tiles_layout_manager->StartRow(0, 0);
     tiles_layout_manager->AddView(tile_item);
     AddChildView(tile_item);
     tile_item->SetParentBackgroundColor(kLabelBackgroundColor);
     tile_item->SetHoverStyle(TileItemView::HOVER_STYLE_ANIMATE_SHADOW);
-    search_result_tile_views_.push_back(tile_item);
+    search_result_tile_views_.emplace_back(tile_item);
   }
 
   // Also add a special "all apps" button to the end of the container.
   all_apps_button_->UpdateIcon();
   if (i % kNumStartPageTilesCols == 0)
     tiles_layout_manager->StartRow(0, 0);
   tiles_layout_manager->AddView(all_apps_button_);
   AddChildView(all_apps_button_);
 }
 
@@ skipping 15 matching lines @@
   // The view containing the start page WebContents and SearchBoxSpacerView.
   InitInstantContainer();
   AddChildView(instant_container_);
 
   // The view containing the start page tiles.
   AddChildView(tiles_container_);
 
   AddChildView(custom_launcher_page_background_);
 
   tiles_container_->SetResults(view_delegate_->GetModel()->results());
-  Reset();
 }
 
 StartPageView::~StartPageView() {
 }
 
 void StartPageView::InitInstantContainer() {
   views::BoxLayout* instant_layout_manager = new views::BoxLayout(
       views::BoxLayout::kVertical, 0, 0, kInstantContainerSpacing);
   instant_layout_manager->set_inside_border_insets(
       gfx::Insets(0, 0, kSearchBoxAndTilesSpacing, 0));
@@ skipping 219 matching lines @@
   // is enabled).
   if (event->type() == ui::ET_SCROLL && event->y_offset() < 0)
     MaybeOpenCustomLauncherPage();
 }
 
 TileItemView* StartPageView::GetTileItemView(size_t index) {
   return tiles_container_->GetTileItemView(index);
 }
 
 }  // namespace app_list