chrome/browser/image_holder.h

   1 // Copyright 2014 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_IMAGE_HOLDER_H_
   6 #define CHROME_BROWSER_IMAGE_HOLDER_H_
   7
   8 #include "base/memory/scoped_vector.h"
   9 #include "chrome/browser/bitmap_fetcher/bitmap_fetcher.h"
  10 #include "ui/gfx/image/image.h"
  11 #include "ui/gfx/image/image_skia.h"
  12 #include "url/gurl.h"
  13
  14 class Profile;
  15
  16 namespace chrome {
  17
  18 // This provides a callback so the ImageHolder can inform its parent when a
  19 // bitmap arrives.
  20 class ImageHolderDelegate {
  21  public:
  22   virtual void OnFetchComplete() = 0;
  23 };
  24
  25 // This class encapsulates the action of fetching a bitmap, reporting when it is
  26 // fetched, and holding onto the bitmap until no longer needed.
  27 class ImageHolder : public chrome::BitmapFetcherDelegate {
  28  public:
  29   ImageHolder(const GURL& low_dpi_url,
  30               const GURL& high_dpi_url,
  31               Profile* profile,
  32               ImageHolderDelegate* delegate);
  33   ~ImageHolder() override;
  34
  35   // Begin fetching of the URLs we have.
  36   void StartFetch();
  37
  38   // Check whether we have a response from the server for these resources,
  39   // even if the response is a failed fetch.
  40   bool IsFetchingDone() const;
  41
  42   // Inherited from BitmapFetcherDelegate
  43   void OnFetchComplete(const GURL url, const SkBitmap* bitmap) override;
  44
  45   // Accessors:
  46   GURL low_dpi_url() const { return low_dpi_url_; }
  47   GURL high_dpi_url() const { return high_dpi_url_; }
  48   gfx::Image low_dpi_image() { return gfx::Image(image_); }
  49
  50  private:
  51   // Helper function to create a bitmap fetcher (but not start the fetch).
  52   void CreateBitmapFetcher(const GURL& url);
  53
  54   GURL low_dpi_url_;
  55   GURL high_dpi_url_;
  56   bool low_dpi_fetched_;
  57   bool high_dpi_fetched_;
  58   gfx::ImageSkia image_;
  59   ImageHolderDelegate* delegate_;
  60   ScopedVector<chrome::BitmapFetcher> fetchers_;
  61   Profile* profile_;
  62
  63   FRIEND_TEST_ALL_PREFIXES(ImageHolderTest, CreateBitmapFetcherTest);
  64   FRIEND_TEST_ALL_PREFIXES(ImageHolderTest, OnFetchCompleteTest);
  65   FRIEND_TEST_ALL_PREFIXES(ImageHolderTest, IsFetchingDoneTest);
  66
  67   DISALLOW_COPY_AND_ASSIGN(ImageHolder);
  68 };
  69
  70 }  // namespace chrome.
  71
  72 #endif  // CHROME_BROWSER_IMAGE_HOLDER_H_