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c++gtkmm

in c++ gtk::drawarea: how to refresh image


I am using gtkmm for a GUI in C++. I have a Gtk::DrawingArea on which I have an image (filename):

class MyArea : public Gtk::DrawingArea
{
public:
    MyArea(string filename)
    {
        m_image = Gdk::Pixbuf::create_from_file(filename.c_str());
    }

    virtual bool on_draw(const Cairo::RefPtr<Cairo::Context>& cr)
    {
        if (!m_image)
            return false;

        Gtk::Allocation allocation = get_allocation();
        const int width  = allocation.get_width();
        const int height = allocation.get_height();

        // Draw the image in the middle of the drawing area, or (if the image is
        // larger than the drawing area) draw the middle part of the image.
        Gdk::Cairo::set_source_pixbuf(cr, m_image, (width - m_image->get_width())/2, (height - m_image->get_height())/2);
        cr->paint();

        return true;
    }
    Glib::RefPtr<Gdk::Pixbuf> m_image;
}

I would like to have a function that change the image (with filename2). But I can't find how to :-/

Could someone help me with this please. Thank You


Solution

  • As a member of your class:

    void change_image(string filename2)
    {
        m_image = Gdk::Pixbuf::create_from_file(filename2.c_str());
        queue_draw();
    }