在GTK2中调整夹点大小

Question

我正在编写一个GTK2应用程序。我想在窗口的右下角添加调整大小夹点，but the API does not provide any functions to do so (gtk_window_set_has_resize_grip()仅限于GTK3)。但是，我可以看到许多使用GTK2编写的带有调整大小夹点的程序(旧版本的Pluma、Caja和Geany等)。我试着查看了Pluma的源代码，并在全球范围内搜索"grip“、"resize_grip”和"resize“等关键字，但这两种情况都没有结果。我希望能有一个详细的关于如何在GTK2中实现调整大小夹点的答案。

Answer 1

static gboolean resize_expose(GtkWidget *area, GdkEventExpose *ev, GdkWindowEdge edge) {
  gint size = MIN(area->allocation.width, area->allocation.height);

  gtk_paint_resize_grip(area->style, area->window,
      gtk_widget_get_state(area),
      &ev->area, area, "grip", edge,
      area->allocation.width - size, area->allocation.height - size,
      size, size);

  return TRUE;
}

static gboolean resize_button(GtkWidget *area, GdkEventButton *ev, GdkWindowEdge edge) {
  if (ev->type != GDK_BUTTON_PRESS)
    return TRUE;

  switch (ev->button) {
  case 1:
    gtk_window_begin_resize_drag(GTK_WINDOW(gtk_widget_get_toplevel(area)), edge,
        ev->button, ev->x_root, ev->y_root, ev->time);
    break;
  case 2:
    gtk_window_begin_move_drag(GTK_WINDOW(gtk_widget_get_toplevel(area)),
        ev->button, ev->x_root, ev->y_root, ev->time);
    break;
  }

  return TRUE;
}

void create_grip(GtkWidget *parent_or_window) {
  GtkWidget *area = gtk_drawing_area_new();
  gtk_widget_set_size_request(area, 18, 18);
  gtk_widget_add_events(area, GDK_BUTTON_PRESS_MASK);
  gtk_box_pack_end(GTK_BOX(parent_or_window), area, FALSE, FALSE, 0);
  g_signal_connect(area, "expose_event", G_CALLBACK(grip_expose),
      GINT_TO_POINTER(GDK_WINDOW_EDGE_SOUTH_EAST));
  g_signal_connect(area, "button_press_event", G_CALLBACK(grip_button),
      GINT_TO_POINTER(GDK_WINDOW_EDGE_SOUTH_EAST));
}