chrome/browser/ui/webui/fileicon_source.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_UI_WEBUI_FILEICON_SOURCE_H_
   6 #define CHROME_BROWSER_UI_WEBUI_FILEICON_SOURCE_H_
   7
   8 #include <string>
   9
  10 #include "base/files/file_path.h"
  11 #include "chrome/browser/icon_manager.h"
  12 #include "chrome/common/cancelable_task_tracker.h"
  13 #include "content/public/browser/url_data_source.h"
  14 #include "ui/base/layout.h"
  15
  16 namespace gfx {
  17 class Image;
  18 }
  19
  20 // FileIconSource is the gateway between network-level chrome:
  21 // requests for favicons and the history backend that serves these.
  22 class FileIconSource : public content::URLDataSource {
  23  public:
  24   explicit FileIconSource();
  25
  26   // content::URLDataSource implementation.
  27   virtual std::string GetSource() const OVERRIDE;
  28   virtual void StartDataRequest(
  29       const std::string& path,
  30       int render_process_id,
  31       int render_frame_id,
  32       const content::URLDataSource::GotDataCallback& callback) OVERRIDE;
  33   virtual std::string GetMimeType(const std::string&) const OVERRIDE;
  34
  35  protected:
  36   virtual ~FileIconSource();
  37
  38   // Once the |path| and |icon_size| has been determined from the request, this
  39   // function is called to perform the actual fetch. Declared as virtual for
  40   // testing.
  41   virtual void FetchFileIcon(
  42       const base::FilePath& path,
  43       ui::ScaleFactor scale_factor,
  44       IconLoader::IconSize icon_size,
  45       const content::URLDataSource::GotDataCallback& callback);
  46
  47  private:
  48   // Contains the necessary information for completing an icon fetch request.
  49   struct IconRequestDetails {
  50     IconRequestDetails();
  51     ~IconRequestDetails();
  52
  53     // The callback to run with the response.
  54     content::URLDataSource::GotDataCallback callback;
  55
  56     // The requested scale factor to respond with.
  57     ui::ScaleFactor scale_factor;
  58   };
  59
  60   // Called when favicon data is available from the history backend.
  61   void OnFileIconDataAvailable(const IconRequestDetails& details,
  62                                gfx::Image* icon);
  63
  64   // Tracks tasks requesting file icons.
  65   CancelableTaskTracker cancelable_task_tracker_;
  66
  67   DISALLOW_COPY_AND_ASSIGN(FileIconSource);
  68 };
  69 #endif  // CHROME_BROWSER_UI_WEBUI_FILEICON_SOURCE_H_