/*
- Copyright (C) 2000-2007 Paul Davis
+ Copyright (C) 2000-2007 Paul Davis
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
#include <gtkmm/treeselection.h>
#include <gtkmm/selectiondata.h>
+#include "gtkmm2ext/visibility.h"
+
namespace Gtkmm2ext {
template<class DataType>
-struct SerializedObjectPointers {
+struct /*LIBGTKMM2EXT_API*/ SerializedObjectPointers {
uint32_t size;
uint32_t cnt;
char type[32];
DataType data[0];
};
-class DnDTreeViewBase : public Gtk::TreeView
+class LIBGTKMM2EXT_API DnDTreeViewBase : public Gtk::TreeView
{
private:
public:
void add_drop_targets (std::list<Gtk::TargetEntry>&);
void add_object_drag (int column, std::string type_name);
+
+ void on_drag_begin (Glib::RefPtr<Gdk::DragContext> const & context) {
+ Gtk::TreeView::on_drag_begin (context);
+ start_object_drag ();
+ }
void on_drag_leave(const Glib::RefPtr<Gdk::DragContext>& context, guint time) {
suggested_action = context->get_suggested_action();
std::list<Gtk::TargetEntry> draggable;
Gdk::DragAction suggested_action;
int data_column;
+ std::string object_type;
+
+ struct DragData {
+ DragData () : source (0) {}
+
+ Gtk::TreeView* source;
+ int data_column;
+ std::string object_type;
+ };
+
+ static DragData drag_data;
+
+ void start_object_drag () {
+ drag_data.source = this;
+ drag_data.data_column = data_column;
+ drag_data.object_type = object_type;
+ }
};
template<class DataType>
-class DnDTreeView : public DnDTreeViewBase
+class /*LIBGTKMM2EXT_API*/ DnDTreeView : public DnDTreeViewBase
{
public:
- DnDTreeView() {}
+ DnDTreeView() {}
~DnDTreeView() {}
- sigc::signal<void,std::string,uint32_t,const DataType*> signal_object_drop;
+ sigc::signal<void,const std::list<DataType>&,Gtk::TreeView*,int,int,Glib::RefPtr<Gdk::DragContext>&> signal_drop;
void on_drag_data_get(const Glib::RefPtr<Gdk::DragContext>& context, Gtk::SelectionData& selection_data, guint info, guint time) {
if (selection_data.get_target() == "GTK_TREE_MODEL_ROW") {
-
+
TreeView::on_drag_data_get (context, selection_data, info, time);
-
- } else if (data_column >= 0) {
-
- Gtk::TreeSelection::ListHandle_Path selection = get_selection()->get_selected_rows ();
- SerializedObjectPointers<DataType>* sr = serialize_pointers (get_model(), &selection, selection_data.get_target());
- selection_data.set (8, (guchar*)sr, sr->size);
+
+ } else if (selection_data.get_target() == object_type) {
+
+ /* we don't care about the data passed around by DnD, but
+ we have to provide something otherwise it will stop.
+ */
+
+ guchar c;
+ selection_data.set (8, (guchar*)&c, 1);
}
}
-
+
void on_drag_data_received(const Glib::RefPtr<Gdk::DragContext>& context, int x, int y, const Gtk::SelectionData& selection_data, guint info, guint time) {
if (suggested_action) {
/* this is a drag motion callback. just update the status to
TreeView::on_drag_data_received (context, x, y, selection_data, info, time);
- } else if (data_column >= 0) {
-
- /* object D-n-D */
-
- const void* data = selection_data.get_data();
- const SerializedObjectPointers<DataType>* sr = reinterpret_cast<const SerializedObjectPointers<DataType> *>(data);
-
- if (sr) {
- signal_object_drop (sr->type, sr->cnt, sr->data);
- }
+
+ } else if (selection_data.get_target() == object_type) {
+ end_object_drag (const_cast<Glib::RefPtr<Gdk::DragContext>& > (context), x, y);
+
} else {
/* some kind of target type added by the app, which will be handled by a signal handler */
}
}
- private:
-
- SerializedObjectPointers<DataType>* serialize_pointers (Glib::RefPtr<Gtk::TreeModel> model,
- Gtk::TreeSelection::ListHandle_Path* selection,
- Glib::ustring type) {
-
- /* this nasty chunk of code is here because X's DnD protocol (probably other graphics UI's too)
- requires that we package up the entire data collection for DnD in a single contiguous region
- (so that it can be trivially copied between address spaces). We don't know the type of DataType so
- we have to mix-and-match C and C++ programming techniques here to get the right result.
-
- The C trick is to use the "someType foo[0];" declaration trick to create a zero-sized array at the
- end of a SerializedObjectPointers<DataType object. Then we allocate a raw memory buffer that extends
- past that array and thus provides space for however many DataType items we actually want to pass
- around.
-
- The C++ trick is to use the placement operator new() syntax to initialize that extra
- memory properly.
- */
-
- uint32_t cnt = selection->size();
- uint32_t sz = (sizeof (DataType) * cnt) + sizeof (SerializedObjectPointers<DataType>);
+ /**
+ * This can be called by the Treeview itself or by some other
+ * object that wants to get the list of dragged items.
+ */
- char* buf = new char[sz];
- SerializedObjectPointers<DataType>* sr = (SerializedObjectPointers<DataType>*) buf;
+ void get_object_drag_data (std::list<DataType>& l, Gtk::TreeView** source) {
- for (uint32_t i = 0; i < cnt; ++i) {
- new ((void *) &sr->data[i]) DataType ();
+ if (drag_data.source == 0) {
+ return;
}
+
+ Glib::RefPtr<Gtk::TreeModel> model = drag_data.source->get_model();
+ DataType v;
+ Gtk::TreeSelection::ListHandle_Path selection = drag_data.source->get_selection()->get_selected_rows ();
- sr->cnt = cnt;
- sr->size = sz;
- snprintf (sr->type, sizeof (sr->type), "%s", type.c_str());
-
- cnt = 0;
-
- for (Gtk::TreeSelection::ListHandle_Path::iterator x = selection->begin(); x != selection->end(); ++x, ++cnt) {
- model->get_iter (*x)->get_value (data_column, sr->data[cnt]);
+ for (Gtk::TreeSelection::ListHandle_Path::iterator x = selection.begin(); x != selection.end(); ++x) {
+ model->get_iter (*x)->get_value (drag_data.data_column, v);
+ l.push_back (v);
}
+
+ *source = drag_data.source;
+ }
- return sr;
+ private:
+ void end_object_drag (Glib::RefPtr<Gdk::DragContext>& context, int x, int y) {
+ std::list<DataType> l;
+ Gtk::TreeView* source;
+ get_object_drag_data (l, &source);
+ signal_drop (l, source, x, y, context);
}
+
};
} // namespace
-
+
#endif /* __gtkmm2ext_dndtreeview_h__ */
projects / ardour.git / blobdiff