--------------------------------------------------------------------------------
https://docs.gtk.org/gtk4/visual_index.html            widgets gallery
https://forge.a-lec.org/gem-graph/gem-graph-client/src/branch/devel/Makefile
https://docs.gtk.org/gtk4/class.Widget.html#height-for-width-geometry-management
//  GtkSizeRequestMode get_request_mode (GtkWidget* widget);
//  gtk_window_set_default_size (GTK_WINDOW (a_box), 30, 400);    <    TO STUDY
https://docs.gtk.org/gtk4/section-text-widget.html     texts
https://docs.gtk.org/gtk4/drag-and-drop.html           drag-and-drop  
https://docs.gtk.org/gtk4/class.GestureZoom.html       GtkGestureZoom
https://docs.gtk.org/gtk4/class.ListView.html
--------------------------------------------------------------------------------


GTK_ORIENTATION_VERTICAL       GTK_ORIENTATION_HORIZONTAL

GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH   GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT   GTK_SIZE_REQUEST_CONSTANT_SIZE

g_signal_connect (button, "clicked", G_CALLBACK (printf("%s\n", text)), text);
g_signal_connect_swapped (button, "clicked", G_CALLBACK (gtk_window_destroy), window);

--------------------------------------------------------------------------------

GtkBox       GtkGrid     GtkRevealer    GtkStack
GtkOverlay   GtkPaned    GtkExpander    GtkFixed

box = gtk_box_new (GTK_ORIENTATION_VERTICAL, 0);
gtk_widget_set_halign (box, GTK_ALIGN_FILL);
gtk_widget_set_valign (box, GTK_ALIGN_CENTER);  //  START  CENTER  END  FILL
gtk_window_set_child (GTK_WINDOW (window), box);
puis, après déclaration du bouton, gtk_box_append (GTK_BOX (box), button);

grid = gtk_grid_new ();
gtk_window_set_child (GTK_WINDOW (window), grid);
button = gtk_button_new_with_label (" I ");               n fois
gtk_grid_attach (GTK_GRID (grid), button, 0, 0, 1, 1);    n fois 

--------------------------------------------------------------------------------

TODO  (or NOT TODO)

GtkWidget *get_text_view(){ //  WTF ?!& @Grr #~!
  //	https://docs.gtk.org/gtk4/section-text-widget.html
  GtkWidget *my_view = gtk_text_view_new ();
  GtkTextTagTable *my_table = gtk_text_tag_table_new ();
  GtkTextBuffer *my_buffer = gtk_text_buffer_new (my_table);

  gtk_text_buffer_set_text (my_buffer, "Hello, this is some text", -1);
  gtk_text_view_set_buffer (GTK_TEXT_VIEW (my_view), my_buffer);

  /* Now you might put the view in a container and display it on the
   * screen; when the user edits the text, signals on the buffer
   * will be emitted, such as "changed", "insert_text", and so on.
   */
  return my_view;
}






/*
https://docs.gtk.org/gtk4/class.ApplicationWindow.html

GtkApplication *app = gtk_application_new ("org.gtk.test", 0);

GtkBuilder *builder = gtk_builder_new_from_string (
    "<interface>"
    "  <menu id='menubar'>"
    "    <submenu>"
    "      <attribute name='label' translatable='yes'>_Edit</attribute>"
    "      <item>"
    "        <attribute name='label' translatable='yes'>_Copy</attribute>"
    "        <attribute name='action'>win.copy</attribute>"
    "      </item>"
    "      <item>"
    "        <attribute name='label' translatable='yes'>_Paste</attribute>"
    "        <attribute name='action'>win.paste</attribute>"
    "      </item>"
    "    </submenu>"
    "  </menu>"
    "</interface>",
    -1);

GMenuModel *menubar = G_MENU_MODEL (gtk_builder_get_object (builder, "menubar"));
gtk_application_set_menubar (GTK_APPLICATION (app), menubar);
g_object_unref (builder);

// ...

GtkWidget *window = gtk_application_window_new (app);

*/
//------------------------------------------------------------------------------

GtkScrolledWindow *get_scrolled_gl_area(){
  GtkScrolledWindow *scrolled = GTK_SCROLLED_WINDOW(gtk_scrolled_window_new());
  gtk_scrolled_window_set_min_content_width  (scrolled, W_IMAGE);
  gtk_scrolled_window_set_min_content_height (scrolled, H_IMAGE);
//  GtkAdjustment *width  = gtk_adjustment_new (600, 300, 1000, 1, 1, 1000);
//  GtkAdjustment *height = gtk_adjustment_new (600, 300, 1000, 1, 1, 1000);
    //      (value, lower, upper, step_increment, page_increment, page_size)
//  GtkWidget *GLarea = gtk_gl_area_new();
//  gtk_scrolled_window_set_child (scrolled, GLarea);
//  https://docs.gtk.org/gtk4/class.GLArea.html
  return scrolled;
}














/*
    essai run-stop, speed et step by step dans une seule box controls
    -----------------------------------------------------------------


#include <stdio.h>
#include <gtk-4.0/gtk/gtk.h>
#include "cold.h"

void print_text(GtkWidget *widget, gpointer data) {g_print (data);}

GtkWidget *get_a_space_test_image(){
  GtkWidget *image;
  image = GTK_WIDGET(get_scrolled_gl_area());
  image = gtk_picture_new_for_filename ("/home/jean/01/Gtk4/images/aXoris.png");
  image = gtk_picture_new_for_filename ("/home/jean/01/Gtk4/images/gg sketch.png");
  image = gtk_picture_new_for_filename ("/home/jean/01/Gtk4/images/E coli.png");
  image = gtk_picture_new_for_filename ("/home/jean/01/Gtk4/images/E coli resized.png");
  image = gtk_picture_new_for_filename ("/home/jean/01/Gtk4/Getting_Started_with_GTK/E coli by David S. Goodsell (2009).png");
  return image;
}

GtkWidget *get_scroll_speed(){
  GtkAdjustment *speed_adjust = gtk_adjustment_new (0, 0, 100, 1, 0, 0);
  GtkWidget *scroll_speed = gtk_scrollbar_new (GTK_ORIENTATION_VERTICAL, speed_adjust);
  return scroll_speed;
}

//  TODO  cliquer sur "RUN"  -->  affiche "STOP"  (et inversement)
GtkBox *get_RUN_STOP_box(){
  GtkBox *RUN_STOP_box = GTK_BOX(gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 2)); // spacing = 2

  GtkWidget *RUN_Label = GTK_WIDGET (gtk_label_new (NULL)); //  "RUN"));
  const char *str = "    RUN\n   STOP";
  const char *format = "<span style=\"oblique\">\%s</span>";
  char *markup;

  markup = g_markup_printf_escaped (format, str);
  gtk_label_set_markup (GTK_LABEL (RUN_Label), markup); //  Sets the labels text and attributes from markup.
  g_free (markup);

  gtk_label_set_max_width_chars (GTK_LABEL(RUN_Label), 12);
  gtk_label_set_wrap (GTK_LABEL(RUN_Label), TRUE);
  gtk_label_set_xalign (GTK_LABEL(RUN_Label), 0.5);  //  xalign value, between 0 and 1
  gtk_label_set_yalign (GTK_LABEL(RUN_Label), 0.5);
  gtk_label_set_selectable (GTK_LABEL(RUN_Label), FALSE); //  default = FALSE
  gtk_label_set_single_line_mode (GTK_LABEL(RUN_Label), TRUE); //  default = TRUE
                                                               //
  gtk_box_append (RUN_STOP_box, RUN_Label);
  return RUN_STOP_box;
}

GtkBox *get_STEP_by_STEP_box(){
  GtkBox *STEP_by_STEP_box = GTK_BOX(gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 0));
  GtkWidget *STEP_by_STEP_Label = GTK_WIDGET (gtk_label_new ("ONE\nSTEP"));
  gtk_box_append (STEP_by_STEP_box, STEP_by_STEP_Label);
  return STEP_by_STEP_box;
}

GtkBox *get_CONTROL_box(){
  GtkBox *CONTROL_box = GTK_BOX(gtk_box_new (GTK_ORIENTATION_VERTICAL, 0));
  gtk_box_append (CONTROL_box, GTK_WIDGET (get_RUN_STOP_box()));
  gtk_box_append (CONTROL_box, GTK_WIDGET (get_scroll_speed()));
  gtk_box_append (CONTROL_box, GTK_WIDGET (get_STEP_by_STEP_box()));
  return CONTROL_box;
}
*/