examples-modeldata.qdoc
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Jani Honkonen
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r919 | /*! | ||
| \example examples/modeldata | ||||
| \title Model data example | ||||
| \subtitle | ||||
| This example shows how to use QAbstractItemModel derived model as the data for the series. | ||||
Marek Rosa
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r935 | |||
| \image modeldata.png | ||||
| Let's start by creating an instance of CustomTableModel class. | ||||
| CustomTableModel class is derived from QAbstractTableModel and it was created for the purpose of this example. | ||||
| The constructor of this class populates the internal data store of the model with the data that is good for our chart example. | ||||
| \snippet ../examples/modeldata/tablewidget.cpp 1 | ||||
| We now have a model with data that we would like to display both on the chart and in a QTableView. | ||||
| First, we create QTableView and tell it use the model as a data source. | ||||
| \snippet ../examples/modeldata/tablewidget.cpp 2 | ||||
| Now we need QChart instance to display the same data on the chart. | ||||
| We also enable animations. It makes it easier to see how modifying the model's data affect the chart. | ||||
| \snippet ../examples/modeldata/tablewidget.cpp 3 | ||||
| Then let's create two QLineSeries and tell them to use the data from the model. | ||||
| First line of the code below creates new line series. Line number two sets the model as the data source for the series. | ||||
| Third line specifies that x coordinates are taken from the model's column(Qt::Vertical) with index 0 and the y coordinates are taken from the model's column with index 1. | ||||
| Finally the series is added to the chart. | ||||
| \snippet ../examples/modeldata/tablewidget.cpp 4 | ||||
| To show in QTableView which data coresponds with which series this example uses table coloring. | ||||
| When series is added to the chart it is assigned a color beased on the currently selected theme. | ||||
| Code below extracts that color from the series and uses it to create colored QTableView. | ||||
| Coloring of the view is not a part of the QChart functionality. | ||||
| \snippet ../examples/modeldata/tablewidget.cpp 5 | ||||
| The same operations are done with second series. Notice that for this series different columns of the same model are mapped. | ||||
| \snippet ../examples/modeldata/tablewidget.cpp 6 | ||||
| \snippet ../examples/modeldata/tablewidget.cpp 7 | ||||
| To avoid setting up the QGraphicsScene we use QChartView class that does it for us. QChart object pointer is used as a parameter of the QChartView constructor. | ||||
| To make the render look nicer Antialiasing is turned on and the minimum size of the chart is set. | ||||
| \snippet ../examples/modeldata/tablewidget.cpp 8 | ||||
| Finally we place both widgets in a layout and use the layout as the application layout. | ||||
| \snippet ../examples/modeldata/tablewidget.cpp 9 | ||||
| Application is ready. Try modifying the data in the table view and see how it affects the chart. | ||||
|
Jani Honkonen
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r919 | */ | ||