How can I scroll to previous data?

[willard1218]

I have a frequently data.
Just like that:

The data will not update when I click stop monitor button.
how do I scroll from right to left to view previous data ?

The only way can scroll when I zoom out the chartView.
But I don't want to zoom out the chartView.

In my project, I will drop first data after 7th data enter,
because I would like the interval of xAxis are always same.
so the xAxis.axisMinimum will be change when data increase,
but I think that is correct way,
I don't like drop any data because when I click stop monitor button,
I would like scroll from right to left to view previous data.

So i would like :

1. The interval of xAxis are always same.
2. The visible data count <= 6, always
3. when I click stop monitor button, I can scroll from right to left to view previous data.

[liuxuan30]

moveViewToAnimated and moveViewToX. or just modify the matrix and refresh (@objc open func refresh(newMatrix: CGAffineTransform, chart: ChartViewBase, invalidate: Bool) -> CGAffineTransform)

[willard1218]

The data continues to come in,
if I don't drop first data after 7-th data come in,
The chart view will become:

but I would like when 7-th data come in, 1-st data will disappear in chartView,
when 8-th data come in, 2-nd data will disappear in chartView,

The max data count of chart view is 6.
and I click stop monitor button, I can scroll from right to left to view previous data.

How can I do this?

[liuxuan30]

have you tried setVisibleXRange?

[willard1218]

Finally, I got a solution.

let numOfVisiableData : CGFloat = 6
let scaleX = CGFloat(dataSet.values.count) / numOfVisiableData

chartView.setScaleMinima(scaleX, scaleY: 1.0)
chartView.xAxis.axisMinimum = xValueOfLastEntry - (numOfVisiableData - 1) * intervalOfX