gtk +，「捕捉」函數的值

Question

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

int mcd(); 

static void num1(GtkWidget *entry1) 
{ 
    const gchar* entry_text; 
    entry_text = gtk_entry_get_text(GTK_ENTRY (entry1)); 
} 

static void num2(GtkWidget *entry2) 
{ 
    const gchar* entry_text; 
    entry_text = gtk_entry_get_text(GTK_ENTRY (entry2)); 
} 

//DA QUI...ho collegato il pulsante "Calcola" con la funzione MCD! 
static void callback(GtkWidget *widget, 
         gpointer data) 
{ 
    int a,b,c; 
    a=22; 
    b=12; 
    c=mcd(a,b); 
    g_print("%d\n", c); 
} 

int mcd(int x, int y){ 
     if(y==0){ 
     return x; 
     } 
    else return mcd(y, x%y); 
} 
//A QUI 

int main(int argc, char *argv[]) { 

    GtkWidget *window; 
    GtkWidget *table; 

    GtkWidget *label1; 
    GtkWidget *label2; 

    GtkWidget *entry1; 
    GtkWidget *entry2; 

    GtkWidget *button; 

    gtk_init(&argc, &argv); 

    window = gtk_window_new(GTK_WINDOW_TOPLEVEL); 
    gtk_window_set_position(GTK_WINDOW(window), GTK_WIN_POS_CENTER); 
    gtk_window_set_title(GTK_WINDOW(window), "MCD Calculator"); 
    gtk_container_set_border_width(GTK_CONTAINER(window), 10); 

    table = gtk_table_new(3, 2, FALSE); 
    gtk_container_add(GTK_CONTAINER(window), table); 

    label1 = gtk_label_new("Num1:"); 
    label2 = gtk_label_new("Num2:"); 


    gtk_table_attach(GTK_TABLE(table), label1, 0, 1, 0, 1, GTK_FILL | GTK_SHRINK, GTK_FILL | GTK_SHRINK, 5, 5); 
    gtk_table_attach(GTK_TABLE(table), label2, 0, 1, 1, 2, GTK_FILL | GTK_SHRINK, GTK_FILL | GTK_SHRINK, 5, 5); 

    entry1 = gtk_entry_new(); 
    g_signal_connect(G_OBJECT(entry1), "activate", G_CALLBACK(num1), &entry1); 
    entry2 = gtk_entry_new(); 
    g_signal_connect(G_OBJECT(entry2), "activate", G_CALLBACK(num2), &entry2); 

    gtk_table_attach(GTK_TABLE(table), entry1, 1, 2, 0, 1, GTK_FILL | GTK_SHRINK, GTK_FILL | GTK_SHRINK, 5, 5); 
    gtk_table_attach(GTK_TABLE(table), entry2, 1, 2, 1, 2, GTK_FILL | GTK_SHRINK, GTK_FILL | GTK_SHRINK, 5, 5); 


    /*Pulsante calcola*/ 
    button = gtk_button_new_with_label ("Calcola"); 
    gtk_container_add (GTK_CONTAINER (window), button); 
    gtk_table_attach (GTK_TABLE (table), button, 1, 5, 7, 8, GTK_FILL | GTK_EXPAND, GTK_FILL | GTK_EXPAND, 0, 0); 
    g_signal_connect (button, "clicked", G_CALLBACK (callback), (gpointer) "Calcola"); 
    /*Fine pulsante calcola*/ 

    gtk_widget_show_all(window); 

    g_signal_connect(window, "destroy", G_CALLBACK(gtk_main_quit), NULL); 

    gtk_main(); 

    return EXIT_SUCCESS; 
} 

我不知道如何從「entry_text」和「entry_text_1」中捕捉數字並將它們用於回調函數。 （所以它會變成：a = entry_text; b = entry_text_1）

Answer 1

您是否試圖訪問按鈕的callback函數中的兩個GtkEntry s的文本？如果是這樣，您需要將參考傳遞給按鈕的信號處理程序。

因此，首先，改變這一行：

g_signal_connect (button, "clicked", G_CALLBACK (callback), (gpointer) "Calcola"); 

要這樣：

GtkWidget *entries[2] = { entry1, entry 2}; 
g_signal_connect (button, "clicked", G_CALLBACK (callback), entries); 

然後，在callback功能：

static void callback(GtkWidget *widget, 
        gpointer data) 
{ 
    GtkWidget *entries = data; 
    int a,b,c; 
    a=atoi(gtk_entry_get_text(GTK_ENTRY(entries[0]))); 
    b=atoi(gtk_entry_get_text(GTK_ENTRY(entries[1]))); 
    c=mcd(a,b); 
    g_print("%d\n", c); 
}