Persistence

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If you build an application in ATL, you have to create your own persistence scheme. The ATL Scribble sample uses a simple comma-separated data format for storing the points to a file. The File Open and File Save common dialog boxes provide the file selection user interface. A sketch is persisted by enumerating over the points that define the user's strokes and writing them to the file, as you can see in this section from CStroke:

 void CStroke::Save(FILE* file) {     int nPoints = m_points.size();     _ftprintf(file, _T("%d\n"), nPoints);     POINTITERATOR it;     for(it = m_points.begin(); it != m_points.end(); it++)     {         POINT pt = *it;         _ftprintf(file, _T("%d,%d\n"), pt.x, pt.y);     } } 

Of course, you can choose whichever file format you prefer, such as XML.



Inside Atl
Inside ATL (Programming Languages/C)
ISBN: 1572318589
EAN: 2147483647
Year: 1998
Pages: 127

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