examples-percentbarchart.qdoc
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Tero Ahola
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r500 | \example examples/percentbarchart | ||
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r387 | \title PercentBarChart Example | ||
| \subtitle | ||||
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r971 | The example shows how to create simple percent bar chart. Percent bar chart shows the data in set as percentage of | ||
| all sets, per category. | ||||
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r971 | Creating percent bar chart is just like creating a regular \l {BarChart Example} {bar chart}, except that for a | ||
| percent bar chart, we use QPercentBarSeries api instead of QBarSeries. Also, in the | ||||
| \l {BarChart Example} {bar chart} we used nice numbers algorithm to make the y axis numbering look better. With | ||||
| percent bar chart there is no need for that, because the maximum y-axis value is always 100. | ||||
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| \image examples_percentbarchart.png | ||||
| The barsets are used in same way in all barcharts. | ||||
| To illustrate difference between various barcharts, we use same data in examples. | ||||
| Data that barchart visualizes, is defined by QBarSet instances. Here we create the sets and append data | ||||
| to them. The data is appended here with << operator. Alternatively the append method could be used. | ||||
| \snippet ../examples/percentbarchart/main.cpp 1 | ||||
| We create the series and append the barsets to it. The series takes ownership of the barsets. The series groups the data from sets to categories. | ||||
| First value of each set are gropuped together at first category second value to second category and so on. | ||||
| \snippet ../examples/percentbarchart/main.cpp 2 | ||||
| Here we create the chart object and add the series to it. We set the title for chart with setTitle and then turn on animations of the series by calling | ||||
| setAnimationOptions(QChart::SeriesAnimations) | ||||
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r492 | \snippet ../examples/percentbarchart/main.cpp 3 | ||
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| To have categories displayed on axis, we need to create a QBarCategoryAxis for that. Here we create a category axis with list of categories and | ||||
| set it to be the x-axis of the chart. The chart takes ownership of axis. For y-axis we use default axis, which is created and scaled to series data | ||||
| by calling createDefaultAxes of the chart. Note that the call for createDefaultAxes must be before we set the category axis. Otherwise the default axis will | ||||
| override the category axis. | ||||
| \snippet ../examples/percentbarchart/main.cpp 4 | ||||
| We also want to show the legend. To do that, we get the legend pointer from chart and set it to visible. We also place the legend to bottom of the chart by setting it's alignment | ||||
| to Qt::AlignBottom. | ||||
| \snippet ../examples/percentbarchart/main.cpp 5 | ||||
| Finally we add the chart onto a view. We also turn on the antialiasing for the chartView. | ||||
| \snippet ../examples/percentbarchart/main.cpp 6 | ||||
| Chart is ready to be shown. We set the chart to be central widget of the window. | ||||
| We also set the size for the chart window and show it. | ||||
| \snippet ../examples/percentbarchart/main.cpp 7 | ||||
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Tero Ahola
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r971 | */ | ||