GTK 获取 slider 值

Question

如何在 GTK 中获取 slider 值？

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

GtkWidget *speed_sld,*speed_label;

static void transmit (GtkWidget *widget,gint *data)
{
  float val = gtk_scale_get_digits(data);
  g_print("Val is %f \n",val);
}

int main (int argc, char *argv[])
{
    GtkBuilder *builder;
    GtkWidget *window;


    gtk_init (&argc, &argv);

    builder = gtk_builder_new ();
    gtk_builder_add_from_file (builder, "./ECU.glade", NULL);

    window = GTK_WIDGET (gtk_builder_get_object (builder, "window1"));
    //g_signal_connect (window, "destroy", G_CALLBACK (on_window_destroy), NULL);

    speed_sld = GTK_WIDGET (gtk_builder_get_object (builder, "scale1"));
    speed_label = GTK_WIDGET (gtk_builder_get_object (builder, "label1"));

    g_signal_connect (speed_sld, "value-changed", G_CALLBACK (transmit), NULL);

    gtk_widget_show_all (window);
    gtk_main ();
}

如何在传输函数中打印 slider 值？我尝试打印数据，*数据等如何获取函数内的值

Answer 1

data 是指向 g_signal_connect 中提供的任何数据的指针(您提供了 NULL)，因此这是没有意义的。

我猜您在查看 GtkScale 文档时感到困惑:记住您还需要查看父小部件 API，在本例中 GtkRange 。这应该有效:

static void transmit (GtkRange *range, gpointer data)
{
  g_print ("current value is %f\n", gtk_range_get_value (range));
}