How can I get current viewport shown x range and scale value

[firetheworld]

Hi, I am use combinedchart and bar chart to show candle stick and volumn, I want there two charts zoomin or zoomout sync and show the same range x when pinch gesture, How can I get current viewport shown x range and scale value?

[liuxuan30]

there are people used to ask similar question, you can search.
Commonly just look at ViewPortHandler functions and ChartTransformer functions