views/drag_utils.cc

   1 // Copyright (c) 2011 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 "views/drag_utils.h"
   6
   7 #include "base/file_util.h"
   8 #include "base/logging.h"
   9 #include "base/utf_string_conversions.h"
  10 #include "googleurl/src/gurl.h"
  11 #include "grit/ui_resources.h"
  12 #include "ui/base/dragdrop/os_exchange_data.h"
  13 #include "ui/base/resource/resource_bundle.h"
  14 #include "ui/gfx/canvas_skia.h"
  15 #include "ui/gfx/font.h"
  16 #include "views/controls/button/text_button.h"
  17
  18 using ui::OSExchangeData;
  19
  20 namespace drag_utils {
  21
  22 // Maximum width of the link drag image in pixels.
  23 static const int kLinkDragImageMaxWidth = 200;
  24 static const int kLinkDragImageVPadding = 3;
  25
  26 // File dragging pixel measurements
  27 static const int kFileDragImageMaxWidth = 200;
  28 static const SkColor kFileDragImageTextColor = SK_ColorBLACK;
  29
  30 void SetURLAndDragImage(const GURL& url,
  31                         const string16& title,
  32                         const SkBitmap& icon,
  33                         OSExchangeData* data) {
  34   DCHECK(url.is_valid() && data);
  35
  36   data->SetURL(url, title);
  37
  38   // Create a button to render the drag image for us.
  39   views::TextButton button(NULL,
  40                            title.empty() ? UTF8ToUTF16(url.spec()) : title);
  41   button.set_max_width(kLinkDragImageMaxWidth);
  42   if (icon.isNull()) {
  43     button.SetIcon(*ResourceBundle::GetSharedInstance().GetBitmapNamed(
  44                    IDR_DEFAULT_FAVICON));
  45   } else {
  46     button.SetIcon(icon);
  47   }
  48   gfx::Size prefsize = button.GetPreferredSize();
  49   button.SetBounds(0, 0, prefsize.width(), prefsize.height());
  50
  51   // Render the image.
  52   gfx::CanvasSkia canvas(prefsize.width(), prefsize.height(), false);
  53   button.PaintButton(&canvas, views::TextButton::PB_FOR_DRAG);
  54   SetDragImageOnDataObject(canvas, prefsize,
  55       gfx::Point(prefsize.width() / 2, prefsize.height() / 2), data);
  56 }
  57
  58 void CreateDragImageForFile(const FilePath& file_name,
  59                             const SkBitmap* icon,
  60                             OSExchangeData* data_object) {
  61   DCHECK(icon);
  62   DCHECK(data_object);
  63
  64   // Set up our text portion
  65   ResourceBundle& rb = ResourceBundle::GetSharedInstance();
  66   gfx::Font font = rb.GetFont(ResourceBundle::BaseFont);
  67
  68   const int width = kFileDragImageMaxWidth;
  69   // Add +2 here to allow room for the halo.
  70   const int height = font.GetHeight() + icon->height() +
  71                      kLinkDragImageVPadding + 2;
  72   gfx::CanvasSkia canvas(width, height, false /* translucent */);
  73
  74   // Paint the icon.
  75   canvas.DrawBitmapInt(*icon, (width - icon->width()) / 2, 0);
  76
  77   std::wstring name = UTF16ToWide(file_name.BaseName().LossyDisplayName());
  78 #if defined(OS_WIN)
  79   // Paint the file name. We inset it one pixel to allow room for the halo.
  80   canvas.DrawStringWithHalo(name, font, kFileDragImageTextColor, SK_ColorWHITE,
  81                             1, icon->height() + kLinkDragImageVPadding + 1,
  82                             width - 2, font.GetHeight(),
  83                             gfx::Canvas::TEXT_ALIGN_CENTER);
  84 #else
  85   canvas.DrawStringInt(WideToUTF16Hack(name), font, kFileDragImageTextColor,
  86                        0, icon->height() + kLinkDragImageVPadding,
  87                        width, font.GetHeight(), gfx::Canvas::TEXT_ALIGN_CENTER);
  88 #endif
  89
  90   SetDragImageOnDataObject(canvas, gfx::Size(width, height),
  91                            gfx::Point(width / 2, kLinkDragImageVPadding),
  92                            data_object);
  93 }
  94
  95 void SetDragImageOnDataObject(const gfx::Canvas& canvas,
  96                               const gfx::Size& size,
  97                               const gfx::Point& cursor_offset,
  98                               OSExchangeData* data_object) {
  99   SetDragImageOnDataObject(
 100       canvas.AsCanvasSkia()->ExtractBitmap(), size, cursor_offset, data_object);
 101 }
 102
 103 } // namespace drag_utils