chrome/browser/download/download_completion_blocker.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_DOWNLOAD_COMPLETION_BLOCKER_H_
   6 #define CHROME_BROWSER_DOWNLOAD_DOWNLOAD_COMPLETION_BLOCKER_H_
   7
   8 #include "base/callback.h"
   9 #include "base/supports_user_data.h"
  10 #include "content/public/browser/download_item.h"
  11
  12 // A subsystem may use a DownloadCompletionBlocker in conjunction with
  13 // DownloadManagerDelegate::ShouldCompleteDownload() in order to block the
  14 // completion of a DownloadItem. CompleteDownload() will run the most recent
  15 // callback set.
  16 class DownloadCompletionBlocker : public base::SupportsUserData::Data {
  17  public:
  18   DownloadCompletionBlocker();
  19   virtual ~DownloadCompletionBlocker();
  20
  21   bool is_complete() const { return is_complete_; }
  22
  23   void set_callback(const base::Closure& callback) {
  24     if (!is_complete())
  25       callback_ = callback;
  26   }
  27
  28   // Mark this download item as complete with respect to this blocker. (Other
  29   // blockers may continue to block the item.) Run |callback_|. This method may
  30   // only be called once, so |callback_| will only be called once.  Subclasses
  31   // must call the base implementation if they override this method.
  32   virtual void CompleteDownload();
  33
  34  private:
  35   bool is_complete_;
  36   base::Closure callback_;
  37
  38   DISALLOW_COPY_AND_ASSIGN(DownloadCompletionBlocker);
  39 };
  40
  41 #endif  // CHROME_BROWSER_DOWNLOAD_DOWNLOAD_COMPLETION_BLOCKER_H_