Device context overviewClasses: wxBufferedDC, wxBufferedPaintDC, wxDC, wxPostScriptDC, wxMetafileDC, wxMemoryDC, wxPrinterDC, wxScreenDC, wxClientDC, wxPaintDC, wxWindowDC. A wxDC is a device context onto which graphics and text can be drawn. The device context is intended to represent a number of output devices in a generic way, with the same API being used throughout. Some device contexts are created temporarily in order to draw on a window. This is true of wxScreenDC, wxClientDC, wxPaintDC, and wxWindowDC. The following describes the differences between these device contexts and when you should use them.
To use a client, paint or window device context, create an object on the stack with the window as argument, for example:
void MyWindow::OnMyCmd(wxCommandEvent& event) { wxClientDC dc(window); DrawMyPicture(dc); }Try to write code so it is parameterised by wxDC - if you do this, the same piece of code may write to a number of different devices, by passing a different device context. This doesn't work for everything (for example not all device contexts support bitmap drawing) but will work most of the time.
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