Zoom in to see data points + dynamic labels

[swelty33]

I am building a Multi-Line Chart that needs to be able to zoom in and out of based on LARGE number of data points (num data points can be anywhere between 1,000-50,000) and spread over hours of time (x axis). Is there a way to do this currently?

[willdale]

As to the zooming something like:

.frame(width: 300*scale, height: 500)
       .gesture(MagnificationGesture()
              .onChanged({ scale = $0 })
       )

You will need to tweak it to smooth it out.

---

As to dynamic labels, you could do something like:

.frame(width: 300*scale,
       height: 500)
.gesture(MagnificationGesture()
            .onChanged({
                scale = $0
                if scale > 2 {
                    data.dataSets.dataPoints = zoomedData()
                } else {
                    data.dataSets.dataPoints = normalData()
                }
            })
)

func normalData() -> [LineChartDataPoint] {
    let newDataSet = data.dataSets.dataPoints.indices.map { index -> LineChartDataPoint in
        if index % 2 != 0 {
            var dp = data.dataSets.dataPoints[index]
            dp.xAxisLabel = ""
            return dp
        } else {
            return data.dataSets.dataPoints[index]
        }
    }
    return newDataSet
}

func zoomedData() -> [LineChartDataPoint] {
    [
        LineChartDataPoint(value: 12000, xAxisLabel: "M", description: "Monday"),
        LineChartDataPoint(value: 10000, xAxisLabel: "T", description: "Tuesday"),
        LineChartDataPoint(value: 8000 , xAxisLabel: "W", description: "Wednesday"),
        LineChartDataPoint(value: 17500, xAxisLabel: "T", description: "Thursday"),
        LineChartDataPoint(value: 16000, xAxisLabel: "F", description: "Friday"),
        LineChartDataPoint(value: 11000, xAxisLabel: "S", description: "Saturday"),
        LineChartDataPoint(value: 9000 , xAxisLabel: "S", description: "Sunday"),
    ]
}

[swelty33]

Thank you very much! Very helpful and tweaking it to work in my env. Appreciate your hard work and for keeping this library online. Cheers

[Albinzr]

Can you give a simple example for this if possible