如何指定gtk+组合框位置弹出窗口

void gtk_combo_box_popup(GtkComboBox *combo_box);

void gtk_combo_box_set_popup_fixed_position(GtkComboBox *combo_box, gboolean fixed);

#include <gtk/gtk.h>

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

    // 创建一个窗口
    GtkWidget *window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
    gtk_window_set_title(GTK_WINDOW(window), "Combo Box Popup Position");
    gtk_container_set_border_width(GTK_CONTAINER(window), 10);
    gtk_widget_set_size_request(window, 200, 100);
    g_signal_connect(G_OBJECT(window), "destroy", G_CALLBACK(gtk_main_quit), NULL);

    // 创建一个组合框
    GtkWidget *combo_box = gtk_combo_box_new_text();
    gtk_combo_box_append_text(GTK_COMBO_BOX(combo_box), "Option 1");
    gtk_combo_box_append_text(GTK_COMBO_BOX(combo_box), "Option 2");
    gtk_combo_box_append_text(GTK_COMBO_BOX(combo_box), "Option 3");

    // 设置组合框的弹出窗口位置
    gtk_combo_box_set_popup_fixed_position(GTK_COMBO_BOX(combo_box), TRUE);

    // 将组合框添加到窗口中
    gtk_container_add(GTK_CONTAINER(window), combo_box);

    gtk_widget_show_all(window);
    gtk_main();

    return 0;
}