/usr/share/doc/gtkmm-documentation/tutorial/html/sec-progressbar.html

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<th width="60%" align="center">Chapter 7. Miscellaneous Widgets</th>
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<div class="sect1">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="sec-progressbar"></a>ProgressBar</h2></div></div></div>
<p>
Progress bars are used to show the status of an ongoing operation. For
instance, a <code class="classname">ProgressBar</code> can show how much of a task has
been completed.
</p>
<p>
To change the value shown, use the <code class="methodname">set_fraction()</code> method,
passing a <span class="type">double</span> between 0.0 and 1.0 to provide the new percentage.
</p>
<p>
A <code class="classname">ProgressBar</code> is horizontal and left-to-right by default,
but you can change it to a vertical progress bar by using the
<code class="methodname">set_orientation()</code> method.
</p>
<p><a class="ulink" href="http://developer.gnome.org/gtkmm/unstable/classGtk_1_1ProgressBar.html" target="_top">Reference</a></p>
<div class="sect2">
<div class="titlepage"><div><div><h3 class="title">
<a name="progressbar-activity-mode"></a>Activity Mode</h3></div></div></div>
<p>
Besides indicating the amount of progress that has occured, the
progress bar can also be used to indicate that there is some activity;
this is done by placing the progress bar in <span class="emphasis"><em>activity mode</em></span>. In
this mode, the progress bar displays a small rectangle which moves
back and forth. Activity mode is useful in situations where the
progress of an operation cannot be calculated as a value range (e.g.,
receiving a file of unknown length).
</p>
<p>
To do this, you need to call the <code class="methodname">pulse()</code> method at regular
intervals. You can also choose the step size, with the
<code class="methodname">set_pulse_step()</code> method.
</p>
<p>
The progress bar can also display a configurable text
string within its trough, using the <code class="methodname">set_text()</code> method.
</p>
</div>
<div class="sect2">
<div class="titlepage"><div><div><h3 class="title">
<a name="progressbar-example"></a>Example</h3></div></div></div>
<div class="figure">
<a name="figure-progressbar"></a><p class="title"><b>Figure 7.7. ProgressBar</b></p>
<div class="figure-contents"><div class="screenshot"><div><img src="figures/progressbar.png" alt="ProgressBar"></div></div></div>
</div>
<br class="figure-break"><p><a class="ulink" href="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/progressbar?h=master" target="_top">Source Code</a></p>
<p>File: <code class="filename">examplewindow.h</code> (For use with gtkmm 3, not gtkmm 2)
</p>
<pre class="programlisting">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

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

protected:
  //Signal handlers:
  void on_checkbutton_text();
  void on_checkbutton_activity();
  void on_checkbutton_inverted();

  bool on_timeout();
  void on_button_close();

  //Child widgets:
  Gtk::Box m_VBox;
  Gtk::Grid m_Grid;
  Gtk::ProgressBar m_ProgressBar;
  Gtk::Separator m_Separator;
  Gtk::CheckButton m_CheckButton_Text, m_CheckButton_Activity, m_CheckButton_Inverted;
  Gtk::Button m_Button_Close;

  int m_connection_id_timeout;
  bool m_bActivityMode;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</pre>
<p>File: <code class="filename">examplewindow.cc</code> (For use with gtkmm 3, not gtkmm 2)
</p>
<pre class="programlisting">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL, 5),
  m_CheckButton_Text("Show text"),
  m_CheckButton_Activity("Activity mode"),
  m_CheckButton_Inverted("Right to Left"),
  m_Button_Close("Close"),
  m_bActivityMode(false)
{
  set_resizable();
  set_title("Gtk::ProgressBar");

  m_VBox.set_border_width(10);
  add(m_VBox);

  m_VBox.pack_start(m_ProgressBar, Gtk::PACK_SHRINK, 5);
  m_ProgressBar.set_halign(Gtk::ALIGN_CENTER);
  m_ProgressBar.set_valign(Gtk::ALIGN_CENTER);
  m_ProgressBar.set_text("some text");
  m_ProgressBar.set_show_text(false);

  //Add a timer callback to update the value of the progress bar:
  m_connection_id_timeout = Glib::signal_timeout().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_timeout), 50 );

  m_VBox.pack_start(m_Separator, Gtk::PACK_SHRINK);
  m_VBox.pack_start(m_Grid);
  m_Grid.set_row_homogeneous(true);

  //Add a check button to select displaying of the trough text:
  m_Grid.attach(m_CheckButton_Text, 0, 0, 1, 1);
  m_CheckButton_Text.property_margin() = 5;
  m_CheckButton_Text.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_checkbutton_text) );

  //Add a check button to toggle activity mode:
  m_Grid.attach(m_CheckButton_Activity, 0, 1, 1, 1);
  m_CheckButton_Activity.property_margin() = 5;
  m_CheckButton_Activity.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_checkbutton_activity) );

  //Add a check button to select growth from left to right or from right to left:
  m_Grid.attach(m_CheckButton_Inverted, 0, 2, 1, 1);
  m_CheckButton_Inverted.property_margin() = 5;
  m_CheckButton_Inverted.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_checkbutton_inverted) );

  //Add a button to exit the program.
  m_VBox.pack_start(m_Button_Close, Gtk::PACK_SHRINK);
  m_Button_Close.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_close) );
  m_Button_Close.set_can_default();
  m_Button_Close.grab_default();

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_checkbutton_text()
{
  const bool show_text = m_CheckButton_Text.get_active();
  m_ProgressBar.set_show_text(show_text);
}

void ExampleWindow::on_checkbutton_activity()
{
  m_bActivityMode = m_CheckButton_Activity.get_active();

  if(m_bActivityMode)
    m_ProgressBar.pulse();
  else
    m_ProgressBar.set_fraction(0.0);
}

void ExampleWindow::on_checkbutton_inverted()
{
  const bool inverted = m_CheckButton_Inverted.get_active();
  m_ProgressBar.set_inverted(inverted);
}

void ExampleWindow::on_button_close()
{
  hide();
}

/* Update the value of the progress bar so that we get
 * some movement */
bool ExampleWindow::on_timeout()
{
  if(m_bActivityMode)
    m_ProgressBar.pulse();
  else
  {
    double new_val = m_ProgressBar.get_fraction() + 0.01;

    if(new_val &gt; 1.0)
      new_val = 0.0;

    //Set the new value:
    m_ProgressBar.set_fraction(new_val);
  }

  //As this is a timeout function, return true so that it
  //continues to get called
  return true;
}
</pre>
<p>File: <code class="filename">main.cc</code> (For use with gtkmm 3, not gtkmm 2)
</p>
<pre class="programlisting">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

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

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</pre>
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gtkmm-documentation 3.18.0-1 / usr / share / doc / gtkmm-documentation / tutorial / html / sec-progressbar.html
