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<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="sec-treeview-draganddrop"></a>Drag and Drop</h2></div></div></div>
<p>
<code class="classname">Gtk::TreeView</code> already implements simple drag-and-drop
when used with the <code class="classname">Gtk::ListStore</code> or
<code class="classname">Gtk::TreeStore</code> models (since gtk 4.8). If necessary, it also allows you
to implement more complex behavior when items are dragged and dropped, using
the normal <a class="link" href="chapter-draganddrop.html" title="Chapter 19. Drag and Drop">Drag and Drop</a> API.
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<div class="titlepage"><div><div><h3 class="title">
<a name="treeview-reorderable-rows"></a>Reorderable rows</h3></div></div></div>
<p>
If you call <code class="methodname">Gtk::TreeView::set_reorderable()</code> then your
TreeView's items can be moved within the treeview itself. This is demonstrated
in the <code class="classname">TreeStore</code> example.
</p>
<p>However, this does not allow you any control of which items can be dragged, and where they can be dropped.
If you need that extra control then you might create a derived <code class="literal">Gtk::TreeModel</code> from
<code class="literal">Gtk::TreeStore</code> or <code class="literal">Gtk::ListStore</code> and override the
<code class="literal">Gtk::TreeDragSource::row_draggable_vfunc()</code> and
<code class="literal">Gtk::TreeDragDest::row_drop_possible_vfunc()</code> virtual methods.
You can examine the <code class="literal">Gtk::TreeModel::Path</code>s provided and allow or disallow dragging
or dropping by returning <code class="literal">true</code> or <code class="literal">false</code>.</p>
<p>This is demonstrated in the drag_and_drop example.</p>
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