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#include <wx/dcclient.h>
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BEGIN_EVENT_TABLE(wxkitFrame,wxFrame)
    ...
    EVT_PAINT(wxkitFrame::OnPaint)
END_EVENT_TABLE()

...

void wxkitFrame::draw(wxDC & dc)
{
    dc.Clear();
    // Befoglaló téglalap
    dc.SetPen(*wxBLACK_PEN);
    dc.SetBrush(*wxWHITE_BRUSH);
    dc.DrawRectangle(400, 40, 300, 300);
    // Megfigyellő helye (referenciapont)
    dc.SetPen(*wxRED_PEN);
    dc.DrawLine(395 + relX->GetValue(), 35 + relY->GetValue(), 405 + relX->GetValue(), 45 + relY->GetValue());
    dc.DrawLine(405 + relX->GetValue(), 35 + relY->GetValue(), 395 + relX->GetValue(), 45 + relY->GetValue());
    // Pontok
    dc.SetPen(*wxBLUE_PEN);
    int px, py;
    for (int i = 0; i < AbsoluteList->GetItemCount(); i++)
    {
        int x = convert(GetContent(AbsoluteList,i,0));
        int y = convert(GetContent(AbsoluteList,i,1));
        if (i) dc.DrawLine(400 + px, 40 + py, 400 + x, 40 + y);
        dc.DrawCircle(400 + x, 40 + y,5);
        px = x; py = y;
    }
}

void wxkitFrame::Refresh()
{
    wxClientDC dc(Panel1);
	draw(dc);
}

void wxkitFrame::OnPaint(wxPaintEvent & event)
{
    wxPaintDC dc(Panel1);
	draw(dc);
	event.Skip();
}