\n#include <stdio.h>\n#include <stdlib.h>\n#include <string.h>\n#include <gtk\/gtk.h>\nstatic GtkWidget *entry;\ngdouble mm=0.0; \/* define mm for storing first number in operation *\/\ngdouble nn=0.0; \/* define nn for storing second number in operation *\/\ngint operator=0; \/* define an operator symbol for addition, subtrace, dividing, multiplication *\/\ngboolean first=TRUE; \/* define a flag for determining if has another operation before current input or not *\/\ngboolean second=FALSE; \/* deine a flag for nn if input or not input *\/\ngboolean has_dot=FALSE; \/* define a flag for determining if has dot in current input or not *\/\ngboolean has_result=FALSE; \/* define a flag for determing if has a result already or not *\/\ngchar number[100]; \/* define a buffer for storing number *\/\n\nvoid clear()\n{\n int i;\n \/* This function for purpose of clear all flags and numbers *\/\n gtk_entry_set_text(GTK_ENTRY(entry), "0");\n mm=0.0;\n nn=0.0;\n first=FALSE;\n second=FALSE;\n has_dot=FALSE;\n has_result=FALSE;\n for (i=0; 100; i++)\n number[i]='';\n}\n\nvoid number_clear()\n{\n int i;\n for (i=0; 100; i++)\n number[i]='';\n}\n\nvoid calculate_last_time()\n{\n switch (operator)\n {\n case 1:\n \/* Define the operation of addition *\/\n if(second)\n\t{\n\t g_ascii_dtostr(number, 100, mm+nn);\n\t gtk_entry_set_text(GTK_ENTRY(entry), number);\n\t mm=mm+nn; \/* Set the left operand to be result *\/\n\t number_clear();\n\t second=FALSE;\n\t}\n else\n\t{\n\t \/* init second operand *\/\n\t nn=0.0;\n\t number_clear();\n\t}\n break;\n case 2:\n \/* Define the operation of subtrace *\/\n if(second)\n\t{\n\t g_ascii_dtostr(number, 100, mm-nn);\n\t gtk_entry_set_text(GTK_ENTRY(entry), number);\n\t mm=mm-nn;\n\t number_clear();\n\t second=FALSE;\n\t}\n else\n\t{\n\t \/* init second operand (nn) *\/\n\t nn=0.0;\n\t number_clear();\n\t}\n break;\n case 3:\n \/* Define the operation of multiplication *\/\n if(second)\n\t{\n\t g_ascii_dtostr(number, 100, mm*nn);\n\t gtk_entry_set_text(GTK_ENTRY(entry), number);\n\t mm=mm*nn;\n\t number_clear();\n\t second=FALSE;\n\t}\n else\n\t{\n\t number_clear();\n\t nn=0.0;\n\t}\n break;\n case 4:\n \/* Define the operation of dividing *\/\n if(second)\n\t{\n\t g_ascii_dtostr(number, 100, mm\/nn);\n\t gtk_entry_set_text(GTK_ENTRY(entry), number);\n\t mm=mm\/nn;\n\t number_clear();\n\t second=FALSE;\n\t}\n else\n\t{\n\t nn=0.0;\n\t number_clear();\n\t}\n break;\n default:\n number_clear();\n }\n}\n\nvoid on_number_button_clicked(GtkWidget *button, gpointer data)\n{\n const gchar *num; \/* record current input number as char *\/\n num=gtk_button_get_label(GTK_BUTTON(button));\n g_strlcat(number, num, 100);\n if(has_result)\n clear();\n\n if(first==FALSE)\n {\n mm=g_strtod(number, NULL);\n }\n else\n {\n nn=g_strtod(number, NULL);\n second=TRUE;\n }\n\n gtk_entry_set_text(GTK_ENTRY(entry), number); \/* display the number user input in entry box *\/\n}\n\nvoid on_dot_button_clicked(GtkWidget *button, gpointer data)\n{\n if(has_dot)\n ; \/* Nothing to do if current input has a dot already*\/\n else\n {\n has_dot=TRUE;\n g_strlcat(number, ".", 100);\n if(has_result)\n\tclear();\n\n if (first==FALSE)\n\tmm=g_strtod(number, NULL);\n else\n\t{\n\t nn=g_strtod(number, NULL);\n\t second=TRUE;\n\t}\n }\n gtk_entry_set_text(GTK_ENTRY(entry), number);\n}\n\nvoid on_operator_button_clicked(GtkWidget *button, gpointer data)\n{\n\n switch (GPOINTER_TO_INT(data))\n {\n case 1:\n calculate_last_time();\n operator=1;\n has_result=FALSE;\n has_dot=FALSE;\n first=TRUE;\n break;\n case 2:\n calculate_last_time();\n operator=2;\n has_dot=FALSE;\n has_result=FALSE;\n first=TRUE;\n break;\n case 3:\n calculate_last_time();\n operator=3;\n has_dot=FALSE;\n has_result=FALSE;\n first=TRUE;\n break;\n case 4:\n calculate_last_time();\n operator=4;\n has_dot=FALSE;\n has_result=FALSE;\n first=TRUE;\n break;\n }\n}\n\nvoid on_equal_button_clicked(GtkWidget *button, gpointer data)\n{\n if (!has_result)\n {\n calculate_last_time();\n operator=0;\n number_clear();\n has_dot=FALSE;\n has_result=TRUE;\n }\n}\n\nvoid on_clear_button_clicked(GtkWidget *button, gpointer data)\n{\n clear();\n}\n\nint main(int argc, char *argv[])\n{\n GtkWidget *window;\n GtkWidget *vbox;\n GtkWidget *hbox;\n GtkWidget *label;\n GtkWidget *button;\n\n gtk_init(&argc, &argv);\n window=gtk_window_new(GTK_WINDOW_TOPLEVEL);\n g_signal_connect(G_OBJECT(window), "destroy", G_CALLBACK(gtk_main_quit), NULL);\n gtk_window_set_title(GTK_WINDOW(window), "Simple Calculator");\n gtk_window_set_position(GTK_WINDOW(window), GTK_WIN_POS_MOUSE);\n gtk_container_set_border_width(GTK_CONTAINER(window), 10);\n\n vbox=gtk_vbox_new(FALSE, 5);\n gtk_container_add(GTK_CONTAINER(window), vbox);\n\n \/* Following content sets up label and clear button on main window *\/\n hbox=gtk_hbox_new(FALSE, 5);\n label=gtk_label_new("Calculator");\n gtk_box_pack_start(GTK_BOX(hbox), label, FALSE, FALSE, 0);\n\n button=gtk_button_new_with_label("C");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_clear_button_clicked), NULL);\n gtk_box_pack_end(GTK_BOX(hbox), button, FALSE, FALSE, 0);\n gtk_box_pack_start(GTK_BOX(vbox), hbox, TRUE, TRUE, 5);\n\n \/* Following content sets up entry box in main window *\/\n hbox=gtk_hbox_new(FALSE, 0);\n entry=gtk_entry_new();\n gtk_widget_set_direction(entry, GTK_TEXT_DIR_RTL);\n gtk_box_pack_start(GTK_BOX(hbox), entry, TRUE, TRUE, 0);\n gtk_box_pack_start(GTK_BOX(vbox), hbox, TRUE, TRUE, 5);\n\n \/* Sets up first line of buttons *\/\n hbox=gtk_hbox_new(TRUE, 5);\n button=gtk_button_new_with_label("3");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_number_button_clicked), NULL);\n gtk_box_pack_start(GTK_BOX(hbox), button, TRUE, TRUE, 5);\n\n button=gtk_button_new_with_label("2");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_number_button_clicked), NULL);\n gtk_box_pack_start(GTK_BOX(hbox), button, TRUE, TRUE, 5);\n\n button=gtk_button_new_with_label("1");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_number_button_clicked), NULL);\n gtk_box_pack_start(GTK_BOX(hbox), button, TRUE, TRUE, 5);\n\n button=gtk_button_new_with_label("+");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_operator_button_clicked), (gpointer) 1);\n gtk_box_pack_start(GTK_BOX(hbox), button, TRUE, TRUE, 5);\n gtk_box_pack_start(GTK_BOX(vbox), hbox, TRUE, TRUE, 5);\n \/* End of setting up first line of buttons *\/\n\n \/* Sets up second line of buttons *\/\n hbox=gtk_hbox_new(TRUE, 5);\n button=gtk_button_new_with_label("6");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_number_button_clicked), NULL);\n gtk_box_pack_start(GTK_BOX(hbox), button, TRUE, TRUE, 5);\n\n button=gtk_button_new_with_label("5");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_number_button_clicked), NULL);\n gtk_box_pack_start(GTK_BOX(hbox), button, TRUE, TRUE, 5);\n\n button=gtk_button_new_with_label("4");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_number_button_clicked), NULL);\n gtk_box_pack_start(GTK_BOX(hbox), button, TRUE, TRUE, 5);\n\n button=gtk_button_new_with_label("-");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_operator_button_clicked), (gpointer) 2);\n gtk_box_pack_start(GTK_BOX(hbox), button, TRUE, TRUE, 5);\n gtk_box_pack_start(GTK_BOX(vbox), hbox, TRUE, TRUE, 5);\n \/* End of setting up second line of buttons *\/\n\n \/* Sets up third line of buttons *\/\n hbox=gtk_hbox_new(TRUE, 5);\n button=gtk_button_new_with_label("9");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_number_button_clicked), NULL);\n gtk_box_pack_start(GTK_BOX(hbox), button, TRUE, TRUE, 5);\n\n button=gtk_button_new_with_label("8");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_number_button_clicked), NULL);\n gtk_box_pack_start(GTK_BOX(hbox), button, TRUE, TRUE, 5);\n\n button=gtk_button_new_with_label("7");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_number_button_clicked), NULL);\n gtk_box_pack_start(GTK_BOX(hbox), button, TRUE, TRUE, 5);\n\n button=gtk_button_new_with_label("*");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_operator_button_clicked), (gpointer) 3);\n gtk_box_pack_start(GTK_BOX(hbox), button, TRUE, TRUE, 5);\n gtk_box_pack_start(GTK_BOX(vbox), hbox, TRUE, TRUE, 5);\n \/* End of setting up third line of buttons *\/\n\n \/* Sets up fourth line of buttons*\/\n hbox=gtk_hbox_new(TRUE, 5);\n button=gtk_button_new_with_label("0");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_number_button_clicked), NULL);\n gtk_box_pack_start(GTK_BOX(hbox), button, TRUE, TRUE, 5);\n\n button=gtk_button_new_with_label(".");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_dot_button_clicked), NULL);\n gtk_box_pack_start(GTK_BOX(hbox), button, TRUE, TRUE, 5);\n\n button=gtk_button_new_with_label("=");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_equal_button_clicked), NULL);\n gtk_box_pack_start(GTK_BOX(hbox), button, TRUE, TRUE, 5);\n\n button=gtk_button_new_with_label("\/");\n g_signal_connect(G_OBJECT(button), "clicked", G_CALLBACK(on_operator_button_clicked), (gpointer) 4);\n gtk_box_pack_start(GTK_BOX(hbox), button, TRUE, TRUE, 5);\n gtk_box_pack_start(GTK_BOX(vbox), hbox, TRUE, TRUE, 5);\n \/* End of setting up fourth line of buttons *\/\n\n clear();\n gtk_widget_show_all(window);\n gtk_main();\n\n return EXIT_SUCCESS;\n\n}\n<\/pre><\/div>\n\n\u7f16\u8bd1\u547d\u4ee4<\/p>\n
gcc -o calculator calculator.c `pkg-config --libs --clfags gtk+-2.0`\n<\/pre>\n
![\"Calculator\"](\"http:\/\/farm4.static.flickr.com\/3122\/3138498995_198974f649.jpg?v=0\")
<\/p>","protected":false},"excerpt":{"rendered":"