GTK简单版计算器

接下来我们做一个简单版的计算器。

1）获取按钮上的内容。

2）如果获取的内容是“ c ”，则代表进行退格操作，相当于删去最后一个字符。

3）如果获取的内容不是“ c ”，则把每一次获取的内容连接起来，如：

第一次按了 “ 1 ”， 第二次按了 “ + ”， 第三次按了 “ 1 ”， 连起来则变为 “1+1”。

4）如果获取的内容是“ = ”，则需要相应的运算。先把连起来的字符串拆出来，然后再进行相应操作，最后把运算结果重新显示到行编辑上。

完整代码如下：

#include <gtk/gtk.h>
#include <stdio.h>
#include <string.h>

char buf[50] = "";

void deal_num(GtkButton *button, gpointer data)
{
const char *text = gtk_button_get_label(button);

//退个操作
if (0 == strcmp(text, "c")) {
buf[strlen(buf) - 1] = 0;
}
else
{
int a = 0, b = 0;
char c;
strcat(buf,text);

if (0 == strcmp("=", text)) {
printf("text==##%s##\n",text);
sscanf(buf, "%d%c%d", &a, &c, &b);

printf("---------001-----%c--\n",c);
if ('+' == c) {
sprintf(buf,"%d", a+b);
}
else if ('-' == c) {
sprintf(buf, "%d", a-b);
}
else if ('*' == c) {
sprintf(buf, "%d", a*b);
}
else if ('/' == c) {
sprintf(buf, "%d", a/b);
}

}
}

gtk_entry_set_text(GTK_ENTRY(data), buf);

return;
}

int main(int argc,char *argv[])
{
//1.gtk环境初始化
gtk_init(&argc, &argv);

//2.创建一个窗口
GtkWidget *window = gtk_window_new(GTK_WINDOW_TOPLEVEL);

//3.创建一个表格容器5行4列
GtkWidget *table = gtk_table_new(5,4,TRUE);
//将table加入到window中
gtk_container_add(GTK_CONTAINER(window), table);

//4.创建一个行编辑
GtkWidget *entry = gtk_entry_new();
//设置行编辑的内容
gtk_entry_set_text(GTK_ENTRY(entry), "2+2=4");
//设置行编辑不允许编辑，只能显示用
gtk_editable_set_editable(GTK_EDITABLE(entry), FALSE);

//5.创建多个按钮
GtkWidget *button0 = gtk_button_new_with_label("0");//数值键0
GtkWidget *button1 = gtk_button_new_with_label("1");//数值键1
GtkWidget *button2 = gtk_button_new_with_label("2");//数值键2
GtkWidget *button3 = gtk_button_new_with_label("3");//数值键3
GtkWidget *button4 = gtk_button_new_with_label("4");//数值键4
GtkWidget *button5 = gtk_button_new_with_label("5");//数值键5
GtkWidget *button6 = gtk_button_new_with_label("6");//数值键6
GtkWidget *button7 = gtk_button_new_with_label("7");//数值键7
GtkWidget *button8 = gtk_button_new_with_label("8");//数值键8
GtkWidget *button9 = gtk_button_new_with_label("9");//数值键9

GtkWidget *button_add = gtk_button_new_with_label("+");//加号
GtkWidget *button_minus = gtk_button_new_with_label("-");//减号
GtkWidget *button_mul = gtk_button_new_with_label("*");//乘号
GtkWidget *button_div = gtk_button_new_with_label("/");//除号
GtkWidget *button_equal = gtk_button_new_with_label("=");//等号
GtkWidget *button_delete = gtk_button_new_with_label("c");//退格键

//6.布局将上面的按钮均放入table容器中
gtk_table_attach_defaults(GTK_TABLE(table), entry, 0, 4, 0, 1);

gtk_table_attach_defaults(GTK_TABLE(table), button0, 0, 1, 4, 5);
gtk_table_attach_defaults(GTK_TABLE(table), button1, 0, 1, 3, 4);
gtk_table_attach_defaults(GTK_TABLE(table), button2, 1, 2, 3, 4);
gtk_table_attach_defaults(GTK_TABLE(table), button3, 2, 3, 3, 4);
gtk_table_attach_defaults(GTK_TABLE(table), button4, 0, 1, 2, 3);
gtk_table_attach_defaults(GTK_TABLE(table), button5, 1, 2, 2, 3);
gtk_table_attach_defaults(GTK_TABLE(table), button6, 2, 3, 2, 3);
gtk_table_attach_defaults(GTK_TABLE(table), button7, 0, 1, 1, 2);
gtk_table_attach_defaults(GTK_TABLE(table), button8, 1, 2, 1, 2);
gtk_table_attach_defaults(GTK_TABLE(table), button9, 2, 3, 1, 2);

gtk_table_attach_defaults(GTK_TABLE(table), button_add, 1, 2, 4, 5);
gtk_table_attach_defaults(GTK_TABLE(table), button_minus, 2, 3, 4, 5);
gtk_table_attach_defaults(GTK_TABLE(table), button_mul , 3, 4, 2, 3);
gtk_table_attach_defaults(GTK_TABLE(table), button_div, 3, 4, 3, 4);
gtk_table_attach_defaults(GTK_TABLE(table), button_equal, 3, 4, 4, 5);
gtk_table_attach_defaults(GTK_TABLE(table), button_delete, 3, 4, 1, 2);

//7.注册信号函数，把entry传给回调函数deal_num()
g_signal_connect(button0, "pressed", G_CALLBACK(deal_num), entry);
g_signal_connect(button1, "pressed", G_CALLBACK(deal_num), entry);
g_signal_connect(button2, "pressed", G_CALLBACK(deal_num), entry);
g_signal_connect(button3, "pressed", G_CALLBACK(deal_num), entry);
g_signal_connect(button4, "pressed", G_CALLBACK(deal_num), entry);
g_signal_connect(button5, "pressed", G_CALLBACK(deal_num), entry);
g_signal_connect(button6, "pressed", G_CALLBACK(deal_num), entry);
g_signal_connect(button7, "pressed", G_CALLBACK(deal_num), entry);
g_signal_connect(button8, "pressed", G_CALLBACK(deal_num), entry);
g_signal_connect(button9, "pressed", G_CALLBACK(deal_num), entry);

g_signal_connect(button_add, "pressed", G_CALLBACK(deal_num), entry);
g_signal_connect(button_mul, "pressed", G_CALLBACK(deal_num), entry);
g_signal_connect(button_div, "pressed", G_CALLBACK(deal_num), entry);
g_signal_connect(button_minus, "pressed", G_CALLBACK(deal_num), entry);
g_signal_connect(button_equal, "pressed", G_CALLBACK(deal_num), entry);
g_signal_connect(button_delete, "pressed", G_CALLBACK(deal_num), entry);

//7.显示所有控件
gtk_widget_show_all(window);

//8.主事件循环
gtk_main();

return 0;
}

运行结果：



源码下载：http://download.csdn.net/download/lianghe_work/8936329

转自：