1
我已经创建了一个小的绘图区类,现在需要在揭示事件回调期间绘制一个像素图。但是我无法获得任何我试图编译的参数。下面是代码的相关部分...这次调用gdk_get_pixmap需要什么?
类定义...
class set_display_drawing_area : public Gtk::DrawingArea
{
public:
set_display_drawing_area ();
virtual ~set_display_drawing_area();
protected:
virtual bool on_expose_event(GdkEventExpose* event);
private:
GdkPixmap *pixmap_ptr;
};
和暴露回调...
bool set_display_drawing_area::on_expose_event(GdkEventExpose* event)
{
Glib::RefPtr<Gdk::Window> window = get_window();
if (window)
{
Gtk::Allocation allocation = get_allocation();
const int width = allocation.get_width();
const int height = allocation.get_height();
pixmap_ptr = gdk_pixmap_new (window, // <-- What is needed here?
width,
height,
-1);
谢谢。这是做的伎俩。 – 2010-08-29 10:18:04