views/widget/drop_target_gtk.cc - chromium/src - Git at Google

 // Copyright (c) 2011 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 "views/widget/drop_target_gtk.h"

 #include <algorithm>
 #include <iterator>
 #include <string>
 #include <vector>

 #include "base/file_path.h"
 #include "base/utf_string_conversions.h"
 #include "net/base/net_util.h"
 #include "ui/base/dragdrop/drag_drop_types.h"
 #include "ui/base/dragdrop/gtk_dnd_util.h"
 #include "ui/base/dragdrop/os_exchange_data_provider_gtk.h"
 #include "ui/gfx/point.h"
 #include "views/widget/root_view.h"
 #include "views/widget/native_widget_gtk.h"

 using ui::OSExchangeData;

 namespace {

 std::string GdkAtomToString(GdkAtom atom) {
   gchar* c_name = gdk_atom_name(atom);
   std::string name(c_name);
   g_free(c_name);
   return name;
 }

 // Returns true if |name| is a known name of plain text.
 bool IsTextType(const std::string& name) {
   return name == "text/plain" || name == "TEXT" ||
          name == "STRING" || name == "UTF8_STRING" ||
          name == "text/plain;charset=utf-8";
 }

 // Returns the OSExchangeData::Formats in |targets| and all the
 // OSExchangeData::CustomFormats in |type_set|.
 int CalculateTypes(GList* targets, std::set<GdkAtom>* type_set) {
   int types = 0;
   for (GList* element = targets; element;
        element = g_list_next(element)) {
     GdkAtom atom = static_cast<GdkAtom>(element->data);
     type_set->insert(atom);
     if (atom == GDK_TARGET_STRING) {
       types |= OSExchangeData::STRING;
     } else if (atom == ui::GetAtomForTarget(ui::CHROME_NAMED_URL)) {
       types |= OSExchangeData::URL;
     } else if (atom == ui::GetAtomForTarget(ui::TEXT_URI_LIST)) {
       // TEXT_URI_LIST is used for files as well as urls.
       types |= OSExchangeData::URL | OSExchangeData::FILE_NAME;
     } else {
       std::string target_name = GdkAtomToString(atom);
       if (IsTextType(target_name)) {
         types |= OSExchangeData::STRING;
       } else {
         // Assume any unknown data is pickled.
         types |= OSExchangeData::PICKLED_DATA;
       }
     }
   }
   return types;
 }

 }  // namespace

 namespace views {

 DropTargetGtk::DropTargetGtk(internal::RootView* root_view,
                              GdkDragContext* context)
     : helper_(root_view),
       requested_formats_(0),
       waiting_for_data_(false),
       received_drop_(false),
       pending_view_(NULL) {
   std::set<GdkAtom> all_formats;
   int source_formats = CalculateTypes(context->targets, &all_formats);
   data_.reset(new OSExchangeData(new OSExchangeDataProviderGtk(
                                      source_formats, all_formats)));
 }

 DropTargetGtk::~DropTargetGtk() {
 }

 void DropTargetGtk::ResetTargetViewIfEquals(View* view) {
   helper_.ResetTargetViewIfEquals(view);
 }

 void DropTargetGtk::OnDragDataReceived(GdkDragContext* context,
                                        gint x,
                                        gint y,
                                        GtkSelectionData* data,
                                        guint info,
                                        guint time) {
   std::string target_name = GdkAtomToString(data->type);
   if (data->type == GDK_TARGET_STRING || IsTextType(target_name)) {
     guchar* text_data = gtk_selection_data_get_text(data);
     string16 result;
     if (text_data) {
       char* as_char = reinterpret_cast<char*>(text_data);
       UTF8ToUTF16(as_char, strlen(as_char), &result);
       g_free(text_data);
     }
     data_provider().SetString(result);
   } else if (requested_custom_formats_.find(data->type) !=
              requested_custom_formats_.end()) {
     Pickle result;
     if (data->length > 0)
       result = Pickle(reinterpret_cast<char*>(data->data), data->length);
     data_provider().SetPickledData(data->type, result);
   } else if (data->type == ui::GetAtomForTarget(ui::CHROME_NAMED_URL)) {
     GURL url;
     string16 title;
     ui::ExtractNamedURL(data, &url, &title);
     data_provider().SetURL(url, title);
   } else if (data->type == ui::GetAtomForTarget(ui::TEXT_URI_LIST)) {
     std::vector<GURL> urls;
     ui::ExtractURIList(data, &urls);
     if (urls.size() == 1 && urls[0].is_valid()) {
       data_provider().SetURL(urls[0], string16());

       // TEXT_URI_LIST is used for files as well as urls.
       if (urls[0].SchemeIsFile()) {
         FilePath file_path;
         if (net::FileURLToFilePath(urls[0], &file_path))
           data_provider().SetFilename(file_path);
       }
     } else {
       // Consumers of OSExchangeData will see this as an invalid URL. That is,
       // when GetURL is invoked on the OSExchangeData this triggers false to
       // be returned.
       data_provider().SetURL(GURL(), string16());
     }
   }

   if (!data_->HasAllFormats(requested_formats_, requested_custom_formats_))
     return;  // Waiting on more data.

   int drag_operation = ui::DragDropTypes::GdkDragActionToDragOperation(
       context->actions);
   gfx::Point root_view_location(x, y);
   drag_operation = helper_.OnDragOver(*data_, root_view_location,
                                       drag_operation);
   GdkDragAction gdk_action = static_cast<GdkDragAction>(
       ui::DragDropTypes::DragOperationToGdkDragAction(drag_operation));
   if (!received_drop_)
     gdk_drag_status(context, gdk_action, time);

   waiting_for_data_ = false;

   if (pending_view_ && received_drop_) {
     FinishDrop(context, x, y, time);
     // WARNING: we've been deleted.
     return;
   }
 }

 gboolean DropTargetGtk::OnDragDrop(GdkDragContext* context,
                                    gint x,
                                    gint y,
                                    guint time) {
   received_drop_ = true;
   OnDragMotion(context, x, y, time);
   if (!pending_view_) {
     // User isn't over a view, no drop can occur.
     static_cast<NativeWidgetGtk*>(
         helper_.root_view()->GetWidget()->native_widget())->ResetDropTarget();
     // WARNING: we've been deleted.
     return FALSE;
   }

   if (!waiting_for_data_) {
     // We've got all the data now.
     FinishDrop(context, x, y, time);
     // WARNING: we've been deleted.
     return TRUE;
   }
   // We're waiting on data.
   return TRUE;
 }

 void DropTargetGtk::OnDragLeave(GdkDragContext* context, guint time) {
   helper_.OnDragExit();
 }

 gboolean DropTargetGtk::OnDragMotion(GdkDragContext* context,
                                      gint x,
                                      gint y,
                                      guint time) {
   waiting_for_data_ = false;
   gfx::Point root_view_location(x, y);
   pending_view_ =
       helper_.CalculateTargetView(root_view_location, *data_, false);
   if (pending_view_ &&
       (received_drop_ || (pending_view_ != helper_.target_view() &&
                           pending_view_->AreDropTypesRequired()))) {
     // The target requires drop types before it can answer CanDrop,
     // ask for the data now.
     int formats = 0;
     std::set<GdkAtom> custom_formats;
     pending_view_->GetDropFormats(&formats, &custom_formats);
     IntersectFormats(data_provider().known_formats(),
                      data_provider().known_custom_formats(),
                      &formats, &custom_formats);
     if (!data_provider().HasDataForAllFormats(formats, custom_formats)) {
       if (!received_drop_)
         helper_.OnDragExit();

       // The target needs data for all the types before it can test if the
       // drop is valid, but we don't have all the data. Request the data
       // now. When we get back the data we'll update the target.
       RequestFormats(context, formats, custom_formats, time);

       waiting_for_data_ = true;

       return TRUE;
     }
   }

   int drag_operation = ui::DragDropTypes::GdkDragActionToDragOperation(
       context->actions);
   drag_operation = helper_.OnDragOver(*data_, root_view_location,
                                       drag_operation);
   if (!received_drop_) {
     GdkDragAction gdk_action =
         static_cast<GdkDragAction>(
             ui::DragDropTypes::DragOperationToGdkDragAction(drag_operation));
     gdk_drag_status(context, gdk_action, time);
   }
   return TRUE;
 }

 void DropTargetGtk::FinishDrop(GdkDragContext* context,
                                gint x, gint y, guint time) {
   gfx::Point root_view_location(x, y);
   int drag_operation = ui::DragDropTypes::GdkDragActionToDragOperation(
       context->actions);
   drag_operation = helper_.OnDrop(*data_, root_view_location,
                                   drag_operation);
   GdkDragAction gdk_action =
       static_cast<GdkDragAction>(
           ui::DragDropTypes::DragOperationToGdkDragAction(drag_operation));
   gtk_drag_finish(context, gdk_action != 0, (gdk_action & GDK_ACTION_MOVE),
                   time);

   static_cast<NativeWidgetGtk*>(helper_.root_view()->GetWidget()->
       native_widget())->ResetDropTarget();
   // WARNING: we've been deleted.
 }

 void DropTargetGtk::IntersectFormats(int f1, const std::set<GdkAtom>& cf1,
                                      int* f2, std::set<GdkAtom>* cf2) {
   *f2 = (*f2 & f1);
   std::set<GdkAtom> cf;
   std::set_intersection(
       cf1.begin(), cf1.end(), cf2->begin(), cf2->end(),
       std::insert_iterator<std::set<GdkAtom> >(cf, cf.begin()));
   cf.swap(*cf2);
 }

 void DropTargetGtk::RequestFormats(GdkDragContext* context,
                                    int formats,
                                    const std::set<GdkAtom>& custom_formats,
                                    guint time) {
   GtkWidget* widget = static_cast<NativeWidgetGtk*>(helper_.root_view()->
       GetWidget()->native_widget())->window_contents();

   const std::set<GdkAtom>& known_formats =
       data_provider().known_custom_formats();
   if ((formats & OSExchangeData::STRING) != 0 &&
       (requested_formats_ & OSExchangeData::STRING) == 0) {
     requested_formats_ |= OSExchangeData::STRING;
     if (known_formats.count(gdk_atom_intern("UTF8_STRING", false))) {
       gtk_drag_get_data(widget, context,
                         gdk_atom_intern("UTF8_STRING", false), time);
     } else if (known_formats.count(gdk_atom_intern("text/plain;charset=utf-8",
                                                    false))) {
       gtk_drag_get_data(widget, context,
                         gdk_atom_intern("text/plain;charset=utf-8", false),
                         time);
     } else if (known_formats.count(GDK_TARGET_STRING)) {
       gtk_drag_get_data(widget, context, GDK_TARGET_STRING, time);
     } else if (known_formats.count(gdk_atom_intern("text/plain", false))) {
       gtk_drag_get_data(widget, context, gdk_atom_intern("text/plain", false),
                         time);
     } else if (known_formats.count(gdk_atom_intern("TEXT", false))) {
         gtk_drag_get_data(widget, context, gdk_atom_intern("TEXT", false),
                           time);
     } else if (known_formats.count(gdk_atom_intern("STRING", false))) {
       gtk_drag_get_data(widget, context, gdk_atom_intern("STRING", false),
                         time);
     }
   }
   if ((formats & OSExchangeData::URL) != 0 &&
       (requested_formats_ & OSExchangeData::URL) == 0) {
     requested_formats_ |= OSExchangeData::URL;
     if (known_formats.count(ui::GetAtomForTarget(ui::CHROME_NAMED_URL))) {
       gtk_drag_get_data(widget, context,
                         ui::GetAtomForTarget(ui::CHROME_NAMED_URL), time);
     } else if (known_formats.count(
                    ui::GetAtomForTarget(ui::TEXT_URI_LIST))) {
       gtk_drag_get_data(widget, context,
                         ui::GetAtomForTarget(ui::TEXT_URI_LIST), time);
     }
   }
   if (((formats & OSExchangeData::FILE_NAME) != 0) &&
       (requested_formats_ & OSExchangeData::FILE_NAME) == 0) {
     requested_formats_ |= OSExchangeData::FILE_NAME;
     gtk_drag_get_data(widget, context,
                       ui::GetAtomForTarget(ui::TEXT_URI_LIST), time);
   }
   for (std::set<GdkAtom>::const_iterator i = custom_formats.begin();
        i != custom_formats.end(); ++i) {
     if (requested_custom_formats_.find(*i) ==
         requested_custom_formats_.end()) {
       requested_custom_formats_.insert(*i);
       gtk_drag_get_data(widget, context, *i, time);
     }
   }
 }

 OSExchangeDataProviderGtk& DropTargetGtk::data_provider() const {
   return static_cast<OSExchangeDataProviderGtk&>(data_->provider());
 }

 }  // namespace views
	// Copyright (c) 2011 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 "views/widget/drop_target_gtk.h"

	#include <algorithm>
	#include <iterator>
	#include <string>
	#include <vector>

	#include "base/file_path.h"
	#include "base/utf_string_conversions.h"
	#include "net/base/net_util.h"
	#include "ui/base/dragdrop/drag_drop_types.h"
	#include "ui/base/dragdrop/gtk_dnd_util.h"
	#include "ui/base/dragdrop/os_exchange_data_provider_gtk.h"
	#include "ui/gfx/point.h"
	#include "views/widget/root_view.h"
	#include "views/widget/native_widget_gtk.h"

	using ui::OSExchangeData;

	namespace {

	std::string GdkAtomToString(GdkAtom atom) {
	gchar* c_name = gdk_atom_name(atom);
	std::string name(c_name);
	g_free(c_name);
	return name;
	}

	// Returns true if \|name\| is a known name of plain text.
	bool IsTextType(const std::string& name) {
	return name == "text/plain" \|\| name == "TEXT" \|\|
	name == "STRING" \|\| name == "UTF8_STRING" \|\|
	name == "text/plain;charset=utf-8";
	}

	// Returns the OSExchangeData::Formats in \|targets\| and all the
	// OSExchangeData::CustomFormats in \|type_set\|.
	int CalculateTypes(GList* targets, std::set<GdkAtom>* type_set) {
	int types = 0;
	for (GList* element = targets; element;
	element = g_list_next(element)) {
	GdkAtom atom = static_cast<GdkAtom>(element->data);
	type_set->insert(atom);
	if (atom == GDK_TARGET_STRING) {
	types \|= OSExchangeData::STRING;
	} else if (atom == ui::GetAtomForTarget(ui::CHROME_NAMED_URL)) {
	types \|= OSExchangeData::URL;
	} else if (atom == ui::GetAtomForTarget(ui::TEXT_URI_LIST)) {
	// TEXT_URI_LIST is used for files as well as urls.
	types \|= OSExchangeData::URL \| OSExchangeData::FILE_NAME;
	} else {
	std::string target_name = GdkAtomToString(atom);
	if (IsTextType(target_name)) {
	types \|= OSExchangeData::STRING;
	} else {
	// Assume any unknown data is pickled.
	types \|= OSExchangeData::PICKLED_DATA;
	}
	}
	}
	return types;
	}

	} // namespace

	namespace views {

	DropTargetGtk::DropTargetGtk(internal::RootView* root_view,
	GdkDragContext* context)
	: helper_(root_view),
	requested_formats_(0),
	waiting_for_data_(false),
	received_drop_(false),
	pending_view_(NULL) {
	std::set<GdkAtom> all_formats;
	int source_formats = CalculateTypes(context->targets, &all_formats);
	data_.reset(new OSExchangeData(new OSExchangeDataProviderGtk(
	source_formats, all_formats)));
	}

	DropTargetGtk::~DropTargetGtk() {
	}

	void DropTargetGtk::ResetTargetViewIfEquals(View* view) {
	helper_.ResetTargetViewIfEquals(view);
	}

	void DropTargetGtk::OnDragDataReceived(GdkDragContext* context,
	gint x,
	gint y,
	GtkSelectionData* data,
	guint info,
	guint time) {
	std::string target_name = GdkAtomToString(data->type);
	if (data->type == GDK_TARGET_STRING \|\| IsTextType(target_name)) {
	guchar* text_data = gtk_selection_data_get_text(data);
	string16 result;
	if (text_data) {
	char* as_char = reinterpret_cast<char*>(text_data);
	UTF8ToUTF16(as_char, strlen(as_char), &result);
	g_free(text_data);
	}
	data_provider().SetString(result);
	} else if (requested_custom_formats_.find(data->type) !=
	requested_custom_formats_.end()) {
	Pickle result;
	if (data->length > 0)
	result = Pickle(reinterpret_cast<char*>(data->data), data->length);
	data_provider().SetPickledData(data->type, result);
	} else if (data->type == ui::GetAtomForTarget(ui::CHROME_NAMED_URL)) {
	GURL url;
	string16 title;
	ui::ExtractNamedURL(data, &url, &title);
	data_provider().SetURL(url, title);
	} else if (data->type == ui::GetAtomForTarget(ui::TEXT_URI_LIST)) {
	std::vector<GURL> urls;
	ui::ExtractURIList(data, &urls);
	if (urls.size() == 1 && urls[0].is_valid()) {
	data_provider().SetURL(urls[0], string16());

	// TEXT_URI_LIST is used for files as well as urls.
	if (urls[0].SchemeIsFile()) {
	FilePath file_path;
	if (net::FileURLToFilePath(urls[0], &file_path))
	data_provider().SetFilename(file_path);
	}
	} else {
	// Consumers of OSExchangeData will see this as an invalid URL. That is,
	// when GetURL is invoked on the OSExchangeData this triggers false to
	// be returned.
	data_provider().SetURL(GURL(), string16());
	}
	}

	if (!data_->HasAllFormats(requested_formats_, requested_custom_formats_))
	return; // Waiting on more data.

	int drag_operation = ui::DragDropTypes::GdkDragActionToDragOperation(
	context->actions);
	gfx::Point root_view_location(x, y);
	drag_operation = helper_.OnDragOver(*data_, root_view_location,
	drag_operation);
	GdkDragAction gdk_action = static_cast<GdkDragAction>(
	ui::DragDropTypes::DragOperationToGdkDragAction(drag_operation));
	if (!received_drop_)
	gdk_drag_status(context, gdk_action, time);

	waiting_for_data_ = false;

	if (pending_view_ && received_drop_) {
	FinishDrop(context, x, y, time);
	// WARNING: we've been deleted.
	return;
	}
	}

	gboolean DropTargetGtk::OnDragDrop(GdkDragContext* context,
	gint x,
	gint y,
	guint time) {
	received_drop_ = true;
	OnDragMotion(context, x, y, time);
	if (!pending_view_) {
	// User isn't over a view, no drop can occur.
	static_cast<NativeWidgetGtk*>(
	helper_.root_view()->GetWidget()->native_widget())->ResetDropTarget();
	// WARNING: we've been deleted.
	return FALSE;
	}

	if (!waiting_for_data_) {
	// We've got all the data now.
	FinishDrop(context, x, y, time);
	// WARNING: we've been deleted.
	return TRUE;
	}
	// We're waiting on data.
	return TRUE;
	}

	void DropTargetGtk::OnDragLeave(GdkDragContext* context, guint time) {
	helper_.OnDragExit();
	}

	gboolean DropTargetGtk::OnDragMotion(GdkDragContext* context,
	gint x,
	gint y,
	guint time) {
	waiting_for_data_ = false;
	gfx::Point root_view_location(x, y);
	pending_view_ =
	helper_.CalculateTargetView(root_view_location, *data_, false);
	if (pending_view_ &&
	(received_drop_ \|\| (pending_view_ != helper_.target_view() &&
	pending_view_->AreDropTypesRequired()))) {
	// The target requires drop types before it can answer CanDrop,
	// ask for the data now.
	int formats = 0;
	std::set<GdkAtom> custom_formats;
	pending_view_->GetDropFormats(&formats, &custom_formats);
	IntersectFormats(data_provider().known_formats(),
	data_provider().known_custom_formats(),
	&formats, &custom_formats);
	if (!data_provider().HasDataForAllFormats(formats, custom_formats)) {
	if (!received_drop_)
	helper_.OnDragExit();

	// The target needs data for all the types before it can test if the
	// drop is valid, but we don't have all the data. Request the data
	// now. When we get back the data we'll update the target.
	RequestFormats(context, formats, custom_formats, time);

	waiting_for_data_ = true;

	return TRUE;
	}
	}

	int drag_operation = ui::DragDropTypes::GdkDragActionToDragOperation(
	context->actions);
	drag_operation = helper_.OnDragOver(*data_, root_view_location,
	drag_operation);
	if (!received_drop_) {
	GdkDragAction gdk_action =
	static_cast<GdkDragAction>(
	ui::DragDropTypes::DragOperationToGdkDragAction(drag_operation));
	gdk_drag_status(context, gdk_action, time);
	}
	return TRUE;
	}

	void DropTargetGtk::FinishDrop(GdkDragContext* context,
	gint x, gint y, guint time) {
	gfx::Point root_view_location(x, y);
	int drag_operation = ui::DragDropTypes::GdkDragActionToDragOperation(
	context->actions);
	drag_operation = helper_.OnDrop(*data_, root_view_location,
	drag_operation);
	GdkDragAction gdk_action =
	static_cast<GdkDragAction>(
	ui::DragDropTypes::DragOperationToGdkDragAction(drag_operation));
	gtk_drag_finish(context, gdk_action != 0, (gdk_action & GDK_ACTION_MOVE),
	time);

	static_cast<NativeWidgetGtk*>(helper_.root_view()->GetWidget()->
	native_widget())->ResetDropTarget();
	// WARNING: we've been deleted.
	}

	void DropTargetGtk::IntersectFormats(int f1, const std::set<GdkAtom>& cf1,
	int* f2, std::set<GdkAtom>* cf2) {
	f2 = (f2 & f1);
	std::set<GdkAtom> cf;
	std::set_intersection(
	cf1.begin(), cf1.end(), cf2->begin(), cf2->end(),
	std::insert_iterator<std::set<GdkAtom> >(cf, cf.begin()));
	cf.swap(*cf2);
	}

	void DropTargetGtk::RequestFormats(GdkDragContext* context,
	int formats,
	const std::set<GdkAtom>& custom_formats,
	guint time) {
	GtkWidget* widget = static_cast<NativeWidgetGtk*>(helper_.root_view()->
	GetWidget()->native_widget())->window_contents();

	const std::set<GdkAtom>& known_formats =
	data_provider().known_custom_formats();
	if ((formats & OSExchangeData::STRING) != 0 &&
	(requested_formats_ & OSExchangeData::STRING) == 0) {
	requested_formats_ \|= OSExchangeData::STRING;
	if (known_formats.count(gdk_atom_intern("UTF8_STRING", false))) {
	gtk_drag_get_data(widget, context,
	gdk_atom_intern("UTF8_STRING", false), time);
	} else if (known_formats.count(gdk_atom_intern("text/plain;charset=utf-8",
	false))) {
	gtk_drag_get_data(widget, context,
	gdk_atom_intern("text/plain;charset=utf-8", false),
	time);
	} else if (known_formats.count(GDK_TARGET_STRING)) {
	gtk_drag_get_data(widget, context, GDK_TARGET_STRING, time);
	} else if (known_formats.count(gdk_atom_intern("text/plain", false))) {
	gtk_drag_get_data(widget, context, gdk_atom_intern("text/plain", false),
	time);
	} else if (known_formats.count(gdk_atom_intern("TEXT", false))) {
	gtk_drag_get_data(widget, context, gdk_atom_intern("TEXT", false),
	time);
	} else if (known_formats.count(gdk_atom_intern("STRING", false))) {
	gtk_drag_get_data(widget, context, gdk_atom_intern("STRING", false),
	time);
	}
	}
	if ((formats & OSExchangeData::URL) != 0 &&
	(requested_formats_ & OSExchangeData::URL) == 0) {
	requested_formats_ \|= OSExchangeData::URL;
	if (known_formats.count(ui::GetAtomForTarget(ui::CHROME_NAMED_URL))) {
	gtk_drag_get_data(widget, context,
	ui::GetAtomForTarget(ui::CHROME_NAMED_URL), time);
	} else if (known_formats.count(
	ui::GetAtomForTarget(ui::TEXT_URI_LIST))) {
	gtk_drag_get_data(widget, context,
	ui::GetAtomForTarget(ui::TEXT_URI_LIST), time);
	}
	}
	if (((formats & OSExchangeData::FILE_NAME) != 0) &&
	(requested_formats_ & OSExchangeData::FILE_NAME) == 0) {
	requested_formats_ \|= OSExchangeData::FILE_NAME;
	gtk_drag_get_data(widget, context,
	ui::GetAtomForTarget(ui::TEXT_URI_LIST), time);
	}
	for (std::set<GdkAtom>::const_iterator i = custom_formats.begin();
	i != custom_formats.end(); ++i) {
	if (requested_custom_formats_.find(*i) ==
	requested_custom_formats_.end()) {
	requested_custom_formats_.insert(*i);
	gtk_drag_get_data(widget, context, *i, time);
	}
	}
	}

	OSExchangeDataProviderGtk& DropTargetGtk::data_provider() const {
	return static_cast<OSExchangeDataProviderGtk&>(data_->provider());
	}

	} // namespace views