【为什么我的JVM能实际使用的内存比-Xmx指定的少？】

#include <gtk/gtk.h>
//按钮的回调函数
void callback(GtkWidget *widget, gpointer  data)
{
g_print("hello again-%s was presswd\n",(gchar *)data);
//使用glib库的g_print在终端打印相应的字符
}
//关闭事件的回调函数
gint delete_event(GtkWidget *widget,GdkEvent *event,gpointer data)
{
gtk_main_quit();
return FALSE;
}
int main(int argc , char *argv[])
{
GtkWidget *window;
GtkWidget *button;
GtkWidget *box1;

gtk_init(&argc,&argv);
window = gtk_window_new(GTK_WINDOW_TOPLEVEL);

gtk_window_set_title(GTK_WINDOW(window),"pstary");

g_signal_connect(G_OBJECT(window),"delete_event",G_CALLBACK(delete_event),NULL);

//设置窗口边框高度
gtk_container_set_border_width(GTK_CONTAINER(window),30);

//创建一个组合框，看不见，只是作为排列构件的工具
box1 = gtk_hbox_new(FALSE,0);

//将组合框加入到主窗口中
gtk_container_add(GTK_CONTAINER(window),box1);

button = gtk_button_new_with_label("button 1");

g_signal_connect(G_OBJECT(button),"clicked",G_CALLBACK(callback),"button 1");

//将按钮加入到组合框中
gtk_box_pack_start(GTK_BOX(box1),button,TRUE,TRUE,0);

//显示按钮
gtk_widget_show(button);

button = gtk_button_new_with_label("button 2");

g_signal_connect(G_OBJECT(button),"clicked",G_CALLBACK(callback),"button 2");

gtk_box_pack_start(GTK_BOX(box1),button,TRUE,TRUE,0);

gtk_widget_show(button);

gtk_widget_show(box1);

gtk_widget_show(window);

gtk_main();

return 0;

}

注意事件和信号回调函数的不同，运行结果如下:





root@ubuntu:~/document/gtk# ./helloworld

hello again-button 1 was presswd

hello again-button 1 was presswd

hello again-button 2 was presswd

hello again-button 2 was presswd

hello again-button 2 was presswd

本文出自 “Linux” 博客，请务必保留此出处http://pstary.blog.51cto.com/1466168/675996