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Visualize value on Qt Chart View

  • Hi everyone,

    So I've been playing around with Qt Charts now that it's available under GPLv3, and I got some trouble displaying data.

    I'm using a QBarSeries to create a bar chart that displays some amount. Everything is fine, but the data visualization is kind of lightweight. I'd like to display the real amount of a bar, say in a tooltip when hovering the bar at least.

    For the moment, There are only 3 or 4 values on the y-axis, but there is no way to know precisely the real value of each bar.

    Am I missing something in the documentation? Do I have to implement it myself ? If so, what do I have to subclass: QChart, QChartView, QLegend, QBarSeries?

  • I missed that example, thanks a lot @VRonin!

    So yeah, I have to subclass a view and do the tooltip like display myself using mapToValue, as I suspected.

    I won't close this post yet, just in case someone else has something to add.

  • OK so this example is about QLineSeries, not QBarSeries, and there is a reason: QLineSeries has clicked(QPointF) and hovered(QPointF, bool) signals, QBarSeries doesn't.

    So I think I'll have to simply implement a BarView that displays the value, using QGraphics framework.

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