如何在Gtk TreeView中实现拖放系统？

#include <gtk/gtk.h>

static void on_drag_data_get(GtkWidget *widget, GdkDragContext *context, GtkSelectionData *data, guint info, guint time) {
    GtkTreeIter iter;
    GtkTreeModel *model = gtk_tree_view_get_model(GTK_TREE_VIEW(widget));
    if (gtk_tree_model_get_iter_from_string(model, &iter, "0")) {
        gchar *text = gtk_tree_model_get_value(model, &iter, 0);
        gtk_selection_data_set_text(data, text, -1);
        g_free(text);
    }
}

static void on_drag_data_received(GtkWidget *widget, GdkDragContext *context, int x, int y, GtkSelectionData *data, guint info, guint time) {
    GtkTreeIter iter;
    GtkTreeModel *model = gtk_tree_view_get_model(GTK_TREE_VIEW(widget));
    if (gtk_selection_data_get_text(data)) {
        const gchar *text = gtk_selection_data_get_text(data);
        gtk_list_store_append(GTK_LIST_STORE(model), &iter);
        gtk_list_store_set(GTK_LIST_STORE(model), &iter, 0, text, -1);
    }
}

static void setup_treeview_drag_and_drop(GtkWidget *treeview) {
    gtk_tree_view_set_reorderable(GTK_TREE_VIEW(treeview), TRUE);
    gtk_drag_source_set(treeview, GDK_BUTTON1_MASK, (GtkTargetEntry[]){ {"text/uri-list", 0, 0}}, 1, GDK_ACTION_MOVE);
    gtk_drag_dest_set(treeview, GTK_DEST_DEFAULT_ALL, (GtkTargetEntry[]){ {"text/uri-list", 0, 0}}, 1, GDK_ACTION_MOVE);
    g_signal_connect(treeview, "drag-data-get", G_CALLBACK(on_drag_data_get), NULL);
    g_signal_connect(treeview, "drag-data-received", G_CALLBACK(on_drag_data_received), NULL);
}

int main(int argc, char *argv[]) {
    gtk_init(&argc, &argv);

    GtkWidget *window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
    GtkWidget *treeview = gtk_tree_view_new();
    GtkListStore *list_store = gtk_list_store_new(1, G_TYPE_STRING);
    gtk_tree_view_set_model(GTK_TREE_VIEW(treeview), GTK_TREE_MODEL(list_store));

    GtkTreeViewColumn *column = gtk_tree_view_column_new_with_attributes("Text", gtk_cell_renderer_text_new(), "text", 0, NULL);
    gtk_tree_view_append_column(GTK_TREE_VIEW(treeview), column);

    setup_treeview_drag_and_drop(treeview);

    gtk_container_add(GTK_CONTAINER(window), treeview);
    gtk_widget_show_all(window);

    gtk_main();

    return 0;
}