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<a name="sec-dnd-signals"></a>Signals</h2></div></div></div>
<p>
When a drop target has accepted a dragged item, certain signals will be
emitted, depending on what action has been selected. For instance, the user
might have held down the <span class="keycap"><strong>Shift</strong></span> key to specify a
<code class="literal">move</code> rather than a <code class="literal">copy</code>. Remember that
the user can only select the actions which you have specified in your calls to
<code class="methodname">Gtk::DragSource::set_actions()</code> and
<code class="methodname">Gtk::DropTarget::set_actions()</code>.
</p>
<p>
The source widget will emit these <code class="classname">DragSource</code> signals:
</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem"><p><code class="literal">drag_begin</code>: Provides a <code class="classname">Gdk::Drag</code>.</p></li>
<li class="listitem"><p><code class="literal">prepare</code>: Shall return a <code class="classname">Gdk::ContentProvider</code>,
with the data to use for the drag that is about to start.</p></li>
<li class="listitem"><p><code class="literal">drag_end</code>: Provides a <code class="classname">Gdk::Drag</code>,
and a <span class="type">bool</span> that tells if the drag was performing a <code class="literal">move</code>
and the data should be deleted.</p></li>
<li class="listitem"><p><code class="literal">drag_cancel</code>: Emitted on the drag source when a drag has failed.</p></li>
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<p>
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<p>
The target widget will emit these <code class="classname">DropTarget</code> signals:
</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem"><p><code class="literal">enter</code>: Provides coordinates.
Shall return the preferred <span class="type">Gdk::DragAction</span>.</p></li>
<li class="listitem"><p><code class="literal">motion</code>: Provides coordinates.
Shall return the preferred <span class="type">Gdk::DragAction</span>.</p></li>
<li class="listitem"><p><code class="literal">leave</code>: Emitted on the drop site when the pointer
leaves the widget.</p></li>
<li class="listitem"><p><code class="literal">accept</code>: Provides a <code class="classname">Gdk::Drop</code>.
You can call the <code class="methodname">status()</code> method of the
<code class="classname">Gdk::Drop</code> to indicate which actions will be accepted.</p></li>
<li class="listitem"><p><code class="literal">drop</code>: Provides the data being dropped and coordinates.
Shall return a <span class="type">bool</span> indicating whether the drop was accepted.</p></li>
</ul></div>
<p>
</p>
<p>
The following signals call only one signal handler when emitted. When you connect
a handler to such a signal, your signal handler must be called before (instead of)
the default handler, otherwise it won't be called. Set the <code class="literal">after</code>
parameter in <code class="methodname">connect()</code> to <code class="literal">false</code>.
</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem"><p><code class="methodname">Gtk::DragSource::signal_prepare()</code></p></li>
<li class="listitem"><p><code class="methodname">Gtk::DropTarget::signal_enter()</code></p></li>
<li class="listitem"><p><code class="methodname">Gtk::DropTarget::signal_motion()</code></p></li>
<li class="listitem"><p><code class="methodname">Gtk::DropTarget::signal_accept()</code></p></li>
<li class="listitem"><p><code class="methodname">Gtk::DropTarget::signal_drop()</code></p></li>
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