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Query1:When will the ActualRangeChanged event will be triggered?
The Actual Range Changed event will be triggered whenever there is a change in the range of the axis.
1.While adding data items if the newly added data item values doesn’t fit in the existing range then the new range will be updated based on the added value.
2.When you are setting zoom position and zoom factor the range of the axis will be changed, so the event is triggered. Currently we don’t have support for VisibleRangeChanged event.
3.While we the window is resized ,the range of the axis will be changed based on the available size of the chart.
4.If you do visual data editing, scrolling, panning, adding new series, sorting ,…etc. (for all the axis range related changes)
Query2: How many ways to change the viewport of the data set ?
1.Zooming changes the view port of the chart area. Zooming can be done by mouse wheeling operation , selection zooming ,pinch zooming or manually setting the zoom factor and zoom position in the chart axis.
Please refer the following UG link to know more about Zooming behavior.
2.By enabling the scrollbar in the axis, which will change the view port of the chart area.
Query3: Regarding ActualRangeChanged event.
1.ActualRangeChanged event will be triggered before calculating the visible range so the visible minimum and visible maximum values will be null. ActualRangeChanged events allows us to set the visible minimum and visible maximum values based on which the axis visible range will be calculated.
2.The zoom position and zoom factor will be changed based on the new visible range after the completion of actual range changed event.
3.Curretly we don’t have any support to set visible minimum and visible maximum values outside the actualrangechanged event.
Please provide us the exact scenario of your requirement which would be helpful to provide you a better solution.