• 填充

    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`