GTK获取滑块值

Question

如何在GTK中获取滑块值？

#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 ();
}

我如何在传输函数中打印滑块值？我尝试打印数据，*数据等如何获取函数中的值

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），因此没有任何意义。

我猜您在查看GtkScale文档时会感到困惑：请记住，您还需要查看父小部件API，在本例中为GtkRange。这应该工作：

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