src/chrome/browser/ui/cocoa/table_row_nsimage_cache.mm

   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 #include "chrome/browser/ui/cocoa/table_row_nsimage_cache.h"
   6
   7 #include "base/logging.h"
   8 #include "ui/gfx/image/image_skia.h"
   9 #include "ui/gfx/image/image_skia_util_mac.h"
  10
  11 TableRowNSImageCache::TableRowNSImageCache(Table* model)
  12     : model_(model),
  13       icon_images_([[NSPointerArray alloc] initWithOptions:
  14           NSPointerFunctionsStrongMemory |
  15           NSPointerFunctionsObjectPersonality]) {
  16   int count = model_->RowCount();
  17   [icon_images_ setCount:count];
  18 }
  19
  20 TableRowNSImageCache::~TableRowNSImageCache() {}
  21
  22 void TableRowNSImageCache::OnModelChanged() {
  23   int count = model_->RowCount();
  24   [icon_images_ setCount:0];
  25   [icon_images_ setCount:count];
  26 }
  27
  28 void TableRowNSImageCache::OnItemsChanged(int start, int length) {
  29   DCHECK_LE(start + length, static_cast<int>([icon_images_ count]));
  30   for (int i = start; i < (start + length); ++i) {
  31     [icon_images_ replacePointerAtIndex:i withPointer:NULL];
  32   }
  33   DCHECK_EQ(model_->RowCount(),
  34             static_cast<int>([icon_images_ count]));
  35 }
  36
  37 void TableRowNSImageCache::OnItemsAdded(int start, int length) {
  38   DCHECK_LE(start, static_cast<int>([icon_images_ count]));
  39
  40   // -[NSPointerArray insertPointer:atIndex:] throws if index == count.
  41   // Instead expand the array with NULLs.
  42   if (start == static_cast<int>([icon_images_ count])) {
  43     [icon_images_ setCount:start + length];
  44   } else {
  45     for (int i = 0; i < length; ++i) {
  46       [icon_images_ insertPointer:NULL atIndex:start];  // Values slide up.
  47     }
  48   }
  49   DCHECK_EQ(model_->RowCount(),
  50             static_cast<int>([icon_images_ count]));
  51 }
  52
  53 void TableRowNSImageCache::OnItemsRemoved(int start, int length) {
  54   DCHECK_LE(start + length, static_cast<int>([icon_images_ count]));
  55   for (int i = 0; i < length; ++i) {
  56     [icon_images_ removePointerAtIndex:start];  // Values slide down.
  57   }
  58   DCHECK_EQ(model_->RowCount(),
  59             static_cast<int>([icon_images_ count]));
  60 }
  61
  62 NSImage* TableRowNSImageCache::GetImageForRow(int row) {
  63   DCHECK_EQ(model_->RowCount(),
  64             static_cast<int>([icon_images_ count]));
  65   DCHECK_GE(row, 0);
  66   DCHECK_LT(row, static_cast<int>([icon_images_ count]));
  67   NSImage* image = static_cast<NSImage*>([icon_images_ pointerAtIndex:row]);
  68   if (!image) {
  69     const gfx::ImageSkia image_skia_icon =
  70         model_->GetIcon(row);
  71     // This means GetIcon() will get called until it returns a non-empty image.
  72     // Empty images are intentionally not cached.
  73     if (!image_skia_icon.isNull()) {
  74       image = gfx::NSImageFromImageSkia(image_skia_icon);
  75       DCHECK(image);
  76       [icon_images_ replacePointerAtIndex:row withPointer:image];
  77     }
  78   }
  79   return image;
  80 }
  81