text: // Copyright (c) 2012 The Chromium Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  #include "ui/views/button_drag_utils.h"
  
  #include "base/strings/utf_string_conversions.h"
  #include "grit/ui_resources.h"
  #include "ui/base/dragdrop/drag_utils.h"
  #include "ui/base/dragdrop/os_exchange_data.h"
  #include "ui/base/resource/resource_bundle.h"
  #include "ui/gfx/canvas.h"
  #include "ui/gfx/image/image.h"
  #include "ui/views/controls/button/text_button.h"
  #include "ui/views/drag_utils.h"
  #include "url/gurl.h"
  
  namespace button_drag_utils {
  
  // Maximum width of the link drag image in pixels.
  static const int kLinkDragImageMaxWidth = 200;
  
  void SetURLAndDragImage(const GURL& url,
                          const string16& title,
                          const gfx::ImageSkia& icon,
                          ui::OSExchangeData* data,
                          views::Widget* widget) {
    DCHECK(url.is_valid() && data);
  
    data->SetURL(url, title);
  
    // Create a button to render the drag image for us.
    views::TextButton button(NULL,
                             title.empty() ? UTF8ToUTF16(url.spec()) : title);
    button.set_max_width(kLinkDragImageMaxWidth);
    if (icon.isNull()) {
      button.SetIcon(*ui::ResourceBundle::GetSharedInstance().GetImageNamed(
                     IDR_DEFAULT_FAVICON).ToImageSkia());
    } else {
      button.SetIcon(icon);
    }
    gfx::Size prefsize = button.GetPreferredSize();
    button.SetBounds(0, 0, prefsize.width(), prefsize.height());
  
    // Render the image.
    scoped_ptr<gfx::Canvas> canvas(
        views::GetCanvasForDragImage(widget, prefsize));
    button.PaintButton(canvas.get(), views::TextButton::PB_FOR_DRAG);
    drag_utils::SetDragImageOnDataObject(*canvas, prefsize,
        gfx::Vector2d(prefsize.width() / 2, prefsize.height() / 2), data);
  }
  
  }  // namespace button_drag_utils
  