填充

当创建一个应用时，你将会想将多个控件放入一个窗口控件。我们的第一个 helloworld 范例仅仅使用了一个控件，因而我们可以只是简单地调用一个gtk_container_add()将控件填充到一个窗口控件。但是当你想要向窗口控件中放置超过一个控件时，控制每一个控件的位置和大小就变得很重要了。这就是接下来要讲的填充。

GTK+自带了大量各种布局的容器，这些容器的目的是控制被添加到他们的子控件的布局。具体可以参考布局容器的概述。
下面的示例显示了GtkGrid容器如何让你如何安排几个按钮：

grid_packingpng

Example 2. Packing buttons

新建一个名为 example-2.c 的文件，写入如下内容:

  1. #include <gtk/gtk.h>
  3. static void
  4. print_hello (GtkWidget *widget,
  5.              gpointer   data)
  6. {
  7.     g_print ("Hello World\n");
  9. }
  11. int main (int   argc, char *argv[])
  12. {
  13.     GtkWidget *window;
  14.     GtkWidget *grid;
  15.     GtkWidget *button;
  17.     /* This is called in all GTK applications. Arguments are parsed
  18.     * from the command line and are returned to the application.
  19.     */
  20.     gtk_init (&argc, &argv);
  22.     /* create a new window, and set its title */
  23.     window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
  24.     gtk_window_set_title (GTK_WINDOW (window), "Grid");
  25.     g_signal_connect (window, "destroy", G_CALLBACK (gtk_main_quit), NULL);
  26.     gtk_container_set_border_width (GTK_CONTAINER (window), 10);
  28.     /* Here we construct the container that is going pack our buttons */
  29.     grid = gtk_grid_new ();
  31.     /* Pack the container in the window */
  32.     gtk_container_add (GTK_CONTAINER (window), grid);
  34.     button = gtk_button_new_with_label ("Button 1");
  35.     g_signal_connect (button, "clicked", G_CALLBACK (print_hello), NULL);
  37.     /* Place the first button in the grid cell (0, 0), and make it fill
  38.     * just 1 cell horizontally and vertically (ie no spanning)
  39.     */
  40.     gtk_grid_attach (GTK_GRID (grid), button, 0, 0, 1, 1);
  42.     button = gtk_button_new_with_label ("Button 2");
  43.     g_signal_connect (button, "clicked", G_CALLBACK (print_hello), NULL);
  45.     /* Place the second button in the grid cell (1, 0), and make it fill
  46.     * just 1 cell horizontally and vertically (ie no spanning)
  47.     */
  48.     gtk_grid_attach (GTK_GRID (grid), button, 1, 0, 1, 1);
  50.     button = gtk_button_new_with_label ("Quit");
  51.     g_signal_connect (button, "clicked", G_CALLBACK (gtk_main_quit), NULL);
  53.     /* Place the Quit button in the grid cell (0, 1), and make it
  54.     * span 2 columns.
  55.     */
  56.     gtk_grid_attach (GTK_GRID (grid), button, 0, 1, 2, 1);
  58.     /* Now that we are done packing our widgets, we show them all
  59.     * in one go, by calling gtk_widget_show_all() on the window.
  60.     * This call recursively calls gtk_widget_show() on all widgets
  61.     * that are contained in the window, directly or indirectly.
  62.     */
  63.     gtk_widget_show_all (window);
  65.     /* All GTK applications must have a gtk_main(). Control ends here
  66.     * and waits for an event to occur (like a key press or a mouse event),
  67.     * until gtk_main_quit() is called.
  68.     */
  69.     gtk_main ();
  71.     return 0;
  72. }

然后在终端输入以下命令用GCC编译程序：

  1. gcc `pkg-config --cflags gtk+-3.0` -o example-2 example-2.c `pkg-config --libs gtk+-3.0`