source: trunk/doc/src/examples/chart.qdoc@ 561

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41
42/*!
43 \example itemviews/chart
44 \title Chart Example
45
46 The Chart example shows how to create a custom view for the model/view framework.
47
48 \image chart-example.png
49
50 In this example, the items in a table model are represented as slices in a pie chart,
51 relying on the flexibility of the model/view architecture to handle custom editing
52 and selection features.
53
54 \bold{Note that you only need to create a new view class if your data requires a
55 specialized representation.} You should first consider using a standard QListView,
56 QTableView, or QTreeView with a custom QItemDelegate subclass if you need to
57 represent data in a special way.
58
59 \omit
60 \section1 PieView Class Definition
61
62 The \c PieView class is a subclass of QAbstractItemView. The base class provides
63 much of the functionality required by view classes, so we only need to provide
64 implementations for three public functions: visualRect(), scrollTo(), and
65 indexAt(). However, the view needs to maintain strict control over its look and
66 feel, so we also provide implementations for a number of other functions:
67
68 \snippet examples/itemviews/chart/pieview.h 0
69
70
71
72 \section1 PieView Class Implementation
73
74 The paint event renders the data from the standard item model as a pie chart.
75 We interpret the data in the following way:
76