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：

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