Make the UI an observer of downloads.

chrome/browser/download/download_item_model.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 "chrome/browser/download/download_item_model.h"
 
 #include "base/i18n/number_formatting.h"
 #include "base/i18n/rtl.h"
 #include "base/string16.h"
 #include "base/supports_user_data.h"
@@ skipping 27 matching lines @@
 
   // Get the DownloadItemModelData object for |download|. Creates a model data
   // object if not found. Always returns a non-NULL pointer, unless OOM.
   static DownloadItemModelData* GetOrCreate(DownloadItem* download);
 
   bool should_show_in_shelf() const { return should_show_in_shelf_; }
   void set_should_show_in_shelf(bool should_show_in_shelf) {
     should_show_in_shelf_ = should_show_in_shelf;
   }
 
+  bool should_notify_ui() const { return should_notify_ui_; }
+  void set_should_notify_ui(bool should_notify_ui) {
+    should_notify_ui_ = should_notify_ui;
+  }
+
  private:
   DownloadItemModelData();
   virtual ~DownloadItemModelData() {}
 
   static const char kKey[];
 
   // Whether the download should be displayed in the download shelf. True by
   // default.
   bool should_show_in_shelf_;
+
+  // Whether the UI should be notified when the download is ready to be
+  // presented.
+  bool should_notify_ui_;
 };
 
 // static
 const char DownloadItemModelData::kKey[] = "DownloadItemModelData key";
 
 // static
 const DownloadItemModelData* DownloadItemModelData::Get(
     const DownloadItem* download) {
   return static_cast<const DownloadItemModelData*>(download->GetUserData(kKey));
 }
 
 // static
 DownloadItemModelData* DownloadItemModelData::GetOrCreate(
     DownloadItem* download) {
   DownloadItemModelData* data =
       static_cast<DownloadItemModelData*>(download->GetUserData(kKey));
   if (data == NULL) {
     data = new DownloadItemModelData();
     download->SetUserData(kKey, data);
   }
   return data;
 }
 
 DownloadItemModelData::DownloadItemModelData()
-    : should_show_in_shelf_(true) {
+    : should_show_in_shelf_(true),
+      should_notify_ui_(false) {
 }
 
 string16 InterruptReasonStatusMessage(int reason) {
   int string_id = 0;
 
   switch (reason) {
     case content::DOWNLOAD_INTERRUPT_REASON_FILE_ACCESS_DENIED:
       string_id = IDS_DOWNLOAD_INTERRUPTED_STATUS_ACCESS_DENIED;
       break;
     case content::DOWNLOAD_INTERRUPT_REASON_FILE_NO_SPACE:
@@ skipping 284 matching lines @@
 bool DownloadItemModel::ShouldShowInShelf() const {
   const DownloadItemModelData* data = DownloadItemModelData::Get(download_);
   return !data || data->should_show_in_shelf();
 }
 
 void DownloadItemModel::SetShouldShowInShelf(bool should_show) {
   DownloadItemModelData* data = DownloadItemModelData::GetOrCreate(download_);
   data->set_should_show_in_shelf(should_show);
 }
 
+bool DownloadItemModel::ShouldNotifyUI() const {
+  const DownloadItemModelData* data = DownloadItemModelData::Get(download_);
+  return data && data->should_notify_ui();
+}
+
+void DownloadItemModel::SetShouldNotifyUI(bool should_notify) {
+  DownloadItemModelData* data = DownloadItemModelData::GetOrCreate(download_);
+  data->set_should_notify_ui(should_notify);
+}
+
 string16 DownloadItemModel::GetProgressSizesString() const {
   string16 size_ratio;
   int64 size = GetCompletedBytes();
   int64 total = GetTotalBytes();
   if (total > 0) {
     ui::DataUnits amount_units = ui::GetByteDisplayUnits(total);
     string16 simple_size = ui::FormatBytesWithUnits(size, amount_units, false);
 
     // In RTL locales, we render the text "size/total" in an RTL context. This
     // is problematic since a string such as "123/456 MB" is displayed
@@ skipping 53 matching lines @@
   }
 
   // In progress download with no known time left and non-zero completed bytes:
   // "100/120 MB" or "100 MB"
   if (GetCompletedBytes() > 0)
     return size_ratio;
 
   // Instead of displaying "0 B" we say "Starting..."
   return l10n_util::GetStringUTF16(IDS_DOWNLOAD_STATUS_STARTING);
 }