C 如何在自定义GtkWidget中添加GtkWidget？

我制作了一个定制的GTK小部件，需要添加一个GTK按钮，以便在定制小部件中继承其信号。自定义小部件是一个时间轴，所以我想使用GTK按钮来避免弄乱鼠标坐标。当用户想要移动按钮所代表的图片或只是延长时间线本身的延迟时，按钮小部件将发出信号，我的生活将更加轻松

当然，该按钮不会显示在时间线上。那是我的问题。我知道我必须把按钮放在一个容器中，但如何在绘图功能中做到这一点？有人知道怎么做吗？我在谷歌上搜索了一下这里，但运气不好

这是自定义小部件绘制功能：

static gboolean img_timeline_draw(GtkWidget *da, cairo_t *cr)
{
  GtkWidget *button; 
  ImgTimelinePrivate *priv = img_timeline_get_instance_private((ImgTimeline*)da);
  gint width = gtk_widget_get_allocated_width(da);
  
  cairo_translate (cr, 0 , 12);

  img_timeline_draw_time_ticks(da, cr, width);
  
  //Video timeline
  cairo_translate (cr, 0 , 20);
  cairo_set_source_rgba(cr, priv->video_background[0], priv->video_background[1], priv->video_background[2], priv->video_background[3]);
  cairo_set_line_width(cr, 1);
  cairo_rectangle(cr, 0,10, width - 2, 59);
  cairo_fill(cr);
  //separator
  cairo_set_source_rgb(cr, 1, 1, 1);
  cairo_rectangle(cr, 0,69, width - 2, 3);
  cairo_fill(cr);
  //Audio timeline
  cairo_set_source_rgba(cr, priv->audio_background[0], priv->audio_background[1], priv->audio_background[2], priv->audio_background[3]);
  cairo_rectangle(cr, 0,72, width - 2, 59);
  cairo_fill(cr);

  button = gtk_button_new_with_label("I'm invisible...");
  gtk_widget_set_realized(button, TRUE);
  gtk_widget_show(button);
  return FALSE;
}

这是主要的：

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

  GtkWidget *window=gtk_window_new(GTK_WINDOW_TOPLEVEL);
  gtk_window_set_title(GTK_WINDOW(window), "Imagination timeline widget");
  gtk_window_set_position(GTK_WINDOW(window), GTK_WIN_POS_CENTER);
  gtk_window_set_default_size(GTK_WINDOW(window), 800, 200);
  g_signal_connect(window, "destroy", G_CALLBACK(gtk_main_quit), NULL);

  GtkWidget *timeline = img_timeline_new();
  g_object_set(timeline, "total_time",        300, NULL);
  g_object_set(timeline, "video_background", "#0084ff", NULL);
  g_object_set(timeline, "audio_background", "#0084ff", NULL);

  gtk_widget_add_events( timeline, GDK_BUTTON1_MOTION_MASK
                         | GDK_POINTER_MOTION_HINT_MASK
                         | GDK_BUTTON_PRESS_MASK
                         | GDK_BUTTON_RELEASE_MASK
                         | GDK_SCROLL_MASK
                         | GDK_KEY_PRESS_MASK );

  GtkWidget *scrolledwindow1 = gtk_scrolled_window_new(NULL, NULL);
  GtkWidget *viewport = gtk_viewport_new(NULL,NULL);
  g_signal_connect( G_OBJECT(timeline), "scroll-event", G_CALLBACK(img_timeline_scroll), scrolledwindow1);

  gtk_widget_set_hexpand(viewport, TRUE);
  gtk_widget_set_vexpand(viewport, TRUE);
  gtk_scrolled_window_set_policy (GTK_SCROLLED_WINDOW (scrolledwindow1), GTK_POLICY_AUTOMATIC, GTK_POLICY_NEVER);
  
  gtk_container_add (GTK_CONTAINER(viewport), timeline);
  gtk_container_add (GTK_CONTAINER(scrolledwindow1), viewport);
  gtk_container_add (GTK_CONTAINER (window), scrolledwindow1);
  gtk_widget_show_all(window);

  gtk_main();
  return 0;
}

---

好的，解决方案是将GtkLayout子类化，而不是将GtkDrawingArea子类化，并在自定义小部件绘图函数中使用gtk_container_propagate_draw（）

好的，解决方案是将GtkLayout子类化，而不是将GtkDrawingArea子类化，并在自定义小部件绘图函数中使用gtk_container_propagate_draw（）