chrome/browser/download/all_download_item_notifier.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_BROWSER_DOWNLOAD_ALL_DOWNLOAD_ITEM_NOTIFIER_H_
   6 #define CHROME_BROWSER_DOWNLOAD_ALL_DOWNLOAD_ITEM_NOTIFIER_H_
   7
   8 #include <set>
   9
  10 #include "content/public/browser/download_manager.h"
  11 #include "content/public/browser/download_item.h"
  12
  13 // AllDownloadItemNotifier observes ALL the DownloadItems on a given
  14 // DownloadManager.
  15 // Clients should use GetManager() instead of storing their own pointer to the
  16 // manager so that they can be sensitive to managers that have gone down.
  17
  18 // Example Usage:
  19 // class DownloadSystemConsumer : public AllDownloadItemNotifier::Observer {
  20 //  public:
  21 //   DownloadSystemConsumer(content::DownloadManager* original_manager,
  22 //            content::DownloadManager* incognito_manager)
  23 //     : original_notifier_(original_manager, this),
  24 //       incognito_notifier_(incognito_manager, this) {
  25 //   }
  26 //
  27 //   virtual void OnDownloadUpdated(
  28 //     content::DownloadManager* manager, content::DownloadItem* item) { ... }
  29 //
  30 //  private:
  31 //   AllDownloadItemNotifier original_notifier_;
  32 //   AllDownloadItemNotifier incognito_notifier_;
  33 // };
  34
  35 class AllDownloadItemNotifier : public content::DownloadManager::Observer,
  36                                 public content::DownloadItem::Observer {
  37  public:
  38   // All of the methods take the DownloadManager so that subclasses can observe
  39   // multiple managers at once and easily distinguish which manager a given item
  40   // belongs to.
  41   class Observer {
  42    public:
  43     Observer() {}
  44     virtual ~Observer() {}
  45
  46     virtual void OnDownloadCreated(
  47         content::DownloadManager* manager, content::DownloadItem* item) {}
  48     virtual void OnDownloadUpdated(
  49         content::DownloadManager* manager, content::DownloadItem* item) {}
  50     virtual void OnDownloadOpened(
  51         content::DownloadManager* manager, content::DownloadItem* item) {}
  52     virtual void OnDownloadRemoved(
  53         content::DownloadManager* manager, content::DownloadItem* item) {}
  54
  55    private:
  56     DISALLOW_COPY_AND_ASSIGN(Observer);
  57   };
  58
  59   AllDownloadItemNotifier(content::DownloadManager* manager,
  60                           Observer* observer);
  61
  62   ~AllDownloadItemNotifier() override;
  63
  64   // Returns NULL if the manager has gone down.
  65   content::DownloadManager* GetManager() const { return manager_; }
  66
  67  private:
  68   // content::DownloadManager::Observer
  69   void ManagerGoingDown(content::DownloadManager* manager) override;
  70   void OnDownloadCreated(content::DownloadManager* manager,
  71                          content::DownloadItem* item) override;
  72
  73   // content::DownloadItem::Observer
  74   void OnDownloadUpdated(content::DownloadItem* item) override;
  75   void OnDownloadOpened(content::DownloadItem* item) override;
  76   void OnDownloadRemoved(content::DownloadItem* item) override;
  77   void OnDownloadDestroyed(content::DownloadItem* item) override;
  78
  79   content::DownloadManager* manager_;
  80   AllDownloadItemNotifier::Observer* observer_;
  81   std::set<content::DownloadItem*> observing_;
  82
  83   DISALLOW_COPY_AND_ASSIGN(AllDownloadItemNotifier);
  84 };
  85
  86 #endif  // CHROME_BROWSER_DOWNLOAD_ALL_DOWNLOAD_ITEM_NOTIFIER_H_