Gtk+ programming example on page 115 - simplest progress bar 2 with steps to write GTK program using anjuta

following gtk+ Programming examples are from books 《 Practical technology ： Development Linux application —— use GTK+ and GDK Development Linux Graphical user interface application 》 The first 115 The content of the page —— The simplest progress bar 2 Incidental use Anjuta Write gtk Procedure steps
Official tutorial website https://developer-old.gnome.org/gnome-devel-demos/3.38/progressbar.c.html.en
This is the simplest progress bar , Its writing methods and ideas are more concise and different , The code format is gtk3.0, It's worth learning ,antuja Is similar to Visual Studio and codeblocks Programming software , however antuja Only linux Version without windows Version of
stay gtk2.0 in window = gtk_window_new (GTK_WINDOW_TOPLEVEL); The close button in the upper right corner of the main window must be accompanied by the close mouse action g_signal_connect (G_OBJECT (window), “destroy”, G_CALLBACK (gtk_main_quit), NULL);
stay gtk3.0 in window = gtk_application_window_new (app); The close button in the upper right corner of the main window has a close function , There is no need to add mouse action

Use Anjuta Write gtk Procedure steps
Please refer to the following official website for introduction anjuta Write gtk Procedure steps
https://developer-old.gnome.org/gnome-devel-demos/3.38/image-viewer.c.html.en
Application—— Programming ——Anjuta
file —— newly build —— project —— Select project type as C Of GTK+( Simple )—— Advance in the upper right corner —— Project name ：ProgressBar5—— Select the item and uncheck add internationalization , Do not check use GtkBuilder Make user interface —— Forward —— application
Click in the left column progressbar5 Triangle icon on the left —— double-click main.c——GtkSourceView Editor , Check remember this option —— determine

Open the following website
https://developer-old.gnome.org/gnome-devel-demos/3.38/progressbar.c.html.en
Copy and paste the source code of the progress to main.c And save

function —— perform —— The Configuration Item dialog box appears , Nothing has to be changed , Click execute directly —— It will automatically configure and make Then run the program at the new terminal

stay openSUSE-Leap-15.3-DVD-x86_64 Of gnome3.34.7 Run in a desktop environment Anjuta 3.28.0, The following is the source code , No modification , It is mainly explained in Chinese

#include <gtk/gtk.h>


static gboolean
fill (gpointer   user_data)
{
    
  GtkWidget *progress_bar = user_data;

  /*  Get the value of the current progress bar  */
  gdouble fraction;
  fraction = gtk_progress_bar_get_fraction (GTK_PROGRESS_BAR (progress_bar));

  /*  Every time this function is called , Add progress bar 10%, The standard way of writing is fraction = fraction + 0.1  Abbreviation for += 0.1*/
  fraction += 0.1;

  /*  according to fraction Sets the length of the progress bar display  */
  gtk_progress_bar_set_fraction (GTK_PROGRESS_BAR (progress_bar), fraction);

  /*  Make sure that the value of the progress bar stays at 1.0 following */
  if (fraction < 1.0) 
    return TRUE;
  
  return FALSE;
}



static void
activate (GtkApplication *app,
          gpointer        user_data)
{
    
  GtkWidget *window;
  GtkWidget *progress_bar;

  gdouble fraction = 0.0;

  /*  Create a window with a title and a default size  */
  window = gtk_application_window_new (app);
  gtk_window_set_title (GTK_WINDOW (window), "ProgressBar Example");
  gtk_window_set_default_size (GTK_WINDOW (window), 220, 20);
 
  /*  Create a progress bar and add it to the window  */
  progress_bar = gtk_progress_bar_new ();
  gtk_container_add (GTK_CONTAINER (window), progress_bar);

  /*  according to fraction Sets the length of the progress bar display , The value of the progress bar must be between 0.0-1.0（ contain 0.0-1.0） Between */
  gtk_progress_bar_set_fraction (GTK_PROGRESS_BAR (progress_bar), fraction);

  /*  every other 500 Run once in milliseconds fill function  */
  g_timeout_add (500, fill, GTK_PROGRESS_BAR (progress_bar));
 
  gtk_widget_show_all (window);
}
 


int
main (int argc, char **argv)
{
    
  GtkApplication *app;
  int status;
 
  app = gtk_application_new ("org.gtk.example", G_APPLICATION_FLAGS_NONE);
  g_signal_connect (app, "activate", G_CALLBACK (activate), NULL);
  status = g_application_run (G_APPLICATION (app), argc, argv);
  g_object_unref (app);
 
  return status;
}

The renderings are as follows