＜Linux＞ Ubuntu 第一个UI应用程序

Ubuntu的桌面是gnome,基于gtk开发的,gtk是C语言开发的,总结来说Ubuntu的桌面是C写的.

本次例程是在Ubuntu 19.10上做的,其它版本类似.

1,安装环境

# 安装编译环境 $ sudo apt-get install build-essential # 安装gtk,截止今天,最新版是3.99,19.10自带3.0 $ sudo apt-get install libgtk-3-dev # 安装示例代码 $ sudo apt-get install gtk-3-examples

2,创建&编译项目

# 直接复制示例工程 cp /usr/share/doc/gtk-3-examples/examples/hello-world.c . # 编译 gcc `pkg-config --cflags gtk+-3.0` -o hello_world hello-world.c `pkg-config --libs gtk+-3.0`

gtk示例hello_world.c代码如下:

#include <gtk/gtk.h> static void print_hello (GtkWidget *widget, gpointer data) { g_print ("Hello World\n"); } static void activate (GtkApplication *app, gpointer user_data) { GtkWidget *window; GtkWidget *button; GtkWidget *button_box; window = gtk_application_window_new (app); gtk_window_set_title (GTK_WINDOW (window), "Window"); gtk_window_set_default_size (GTK_WINDOW (window), 200, 200); button_box = gtk_button_box_new (GTK_ORIENTATION_HORIZONTAL); gtk_container_add (GTK_CONTAINER (window), button_box); button = gtk_button_new_with_label ("Hello World"); g_signal_connect (button, "clicked", G_CALLBACK (print_hello), NULL); g_signal_connect_swapped (button, "clicked", G_CALLBACK (gtk_widget_destroy), window); gtk_container_add (GTK_CONTAINER (button_box), button); 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; }

如果感觉代码比较多,这里还有个简版的:

#include <gtk/gtk.h> int main(int argc,char **argv){ GtkWidget *window; gtk_init(&argc,&argv); window = gtk_window_new(GTK_WINDOW_TOPLEVEL); gtk_window_set_title(GTK_WINDOW(window),"hello world"); gtk_window_set_default_size(GTK_WINDOW(window),400,300); gtk_window_set_position(GTK_WINDOW(window),GTK_WIN_POS_CENTER); gtk_widget_show(window); g_signal_connect_swapped(G_OBJECT(window),"destroy", G_CALLBACK(gtk_main_quit),NULL); gtk_main(); return 0; }

3,查看效果

# 运行程序 ./hello_world