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<a name="sec-dialogs-colordialog"></a>ColorDialog and ColorChooserDialog</h2></div></div></div>

<p>
The <code class="classname">ColorChooserDialog</code> (deprecated since <span class="application">gtkmm</span> 4.10) and
<code class="classname">ColorDialog</code> (available since <span class="application">gtkmm</span> 4.10) allow the user
to choose a color. The <code class="classname">ColorButton</code> (deprecated since <span class="application">gtkmm</span> 4.10)
and <code class="classname">ColorDialogButton</code> (available since <span class="application">gtkmm</span> 4.10) open
a color selection dialog when it is clicked.
</p>

<p><a class="ulink" href="https://gnome.pages.gitlab.gnome.org/gtkmm/classGtk_1_1ColorDialog.html" target="_top">ColorDialog Reference</a></p>
<p><a class="ulink" href="https://gnome.pages.gitlab.gnome.org/gtkmm/classGtk_1_1ColorChooserDialog.html" target="_top">ColorChooserDialog Reference</a></p>

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<div class="titlepage"><div><div><h3 class="title">
<a name="colordialog-example"></a>Example</h3></div></div></div>


<div class="figure">
<a name="figure-dialogs-colordialog"></a><p class="title"><b>Figure 17.3. ColorDialog</b></p>
<div class="figure-contents">
  
  <div class="screenshot">
    <div class="mediaobject"><img src="figures/dialogs_colordialog.png" alt="ColorDialog"></div>
  </div>
</div>
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<br class="figure-break">

<p><a class="ulink" href="https://gitlab.gnome.org/GNOME/gtkmm-documentation/tree/master/examples/book/dialogs/colordialog" target="_top">Source Code</a></p>

<p>File: <code class="filename">examplewindow.h</code> (For use with gtkmm 4)</p>
<pre class="programlisting"><code class="code">#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  ~ExampleWindow() override;

protected:
  //Signal handlers:
  void on_color_button_color_set();
  void on_button_dialog_clicked();
  void on_dialog_finish(const Glib::RefPtr&lt;Gio::AsyncResult&gt;&amp; result);

  //Draw function:
  void on_drawing_area_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr, int width, int height);

  //Child widgets:
  Gtk::Box m_VBox;
  Gtk::ColorDialogButton m_ColorDialogButton;
  Gtk::Button m_Button_Dialog;
  Gtk::DrawingArea m_DrawingArea; //To show the color.

  Glib::RefPtr&lt;Gtk::ColorDialog&gt; m_pDialog;
  Gdk::RGBA m_Color;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</code></pre>
<p>File: <code class="filename">examplewindow.cc</code> (For use with gtkmm 4)</p>
<pre class="programlisting"><code class="code">#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::Orientation::VERTICAL, 5),
  m_Button_Dialog("Choose Color")
{
  set_title("Gtk::ColorDialog example");
  set_default_size(200, 200);

  m_pDialog = Gtk::ColorDialog::create();
  m_ColorDialogButton.set_dialog(m_pDialog);

  set_child(m_VBox);

  m_VBox.append(m_ColorDialogButton);
  m_ColorDialogButton.property_rgba().signal_changed().connect(
    sigc::mem_fun(*this, &amp;ExampleWindow::on_color_button_color_set));

  m_VBox.append(m_Button_Dialog);
  m_Button_Dialog.signal_clicked().connect(sigc::mem_fun(*this,
    &amp;ExampleWindow::on_button_dialog_clicked) );

  //Set start color:
  m_Color.set_red(0.0);
  m_Color.set_green(0.0);
  m_Color.set_blue(1.0);
  m_Color.set_alpha(1.0); //opaque
  m_ColorDialogButton.set_rgba(m_Color);

  m_VBox.append(m_DrawingArea);
  m_DrawingArea.set_expand(true);
  m_DrawingArea.set_draw_func(sigc::mem_fun(*this, &amp;ExampleWindow::on_drawing_area_draw));
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_color_button_color_set()
{
  //Store the chosen color:
  m_Color = m_ColorDialogButton.get_rgba();
  m_DrawingArea.queue_draw();
}

void ExampleWindow::on_button_dialog_clicked()
{
  m_pDialog-&gt;choose_rgba(*this, m_Color,
    sigc::mem_fun(*this, &amp;ExampleWindow::on_dialog_finish));
}

void ExampleWindow::on_dialog_finish(const Glib::RefPtr&lt;Gio::AsyncResult&gt;&amp; result)
{
  try
  {
    // If this call changes the color, it will trigger a call to
    // on_color_button_color_set().
    m_ColorDialogButton.set_rgba(m_pDialog-&gt;choose_rgba_finish(result));

    // This is what you should do if m_ColorDialogButton and
    // on_color_button_color_set() did not exist:
    //m_Color = m_pDialog-&gt;choose_rgba_finish(result);
    //m_DrawingArea.queue_draw();
  }
  catch (const Gtk::DialogError&amp; err)
  {
    // Can be thrown by m_pDialog-&gt;choose_rgba_finish(result).
    std::cout &lt;&lt; "No color selected. " &lt;&lt; err.what() &lt;&lt; std::endl;
  }
  catch (const Glib::Error&amp; err)
  {
    std::cout &lt;&lt; "Unexpected exception. " &lt;&lt; err.what() &lt;&lt; std::endl;
  }
}

void ExampleWindow::on_drawing_area_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr, int, int)
{
  Gdk::Cairo::set_source_rgba(cr, m_Color);
  cr-&gt;paint();
}
</code></pre>
<p>File: <code class="filename">main.cc</code> (For use with gtkmm 4)</p>
<pre class="programlisting"><code class="code">#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create("org.gtkmm.example");

  //Shows the window and returns when it is closed.
  return app-&gt;make_window_and_run&lt;ExampleWindow&gt;(argc, argv);
}
</code></pre>

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