Right, this is a weakness of the way the ChartExtentLink works. I played a lot with it, but can offer you only a workaround: The extent link auto-creates right axes for both charts. By default labels are turned off for these axes - but this blocks the ChartExtentLink to work correctly. Simply turn on the Marks of the right axes (Marks.Visible := true), and the right sides will be aligned, however, the left axes labels will appear also at the right axes.
These are the steps to follow:
- Add the two charts, their series and align them
- Add a TChartExtentLink
- Add the two charts to the LinkedCharts property of the ChartExtentLink
- In order to align the horizontal axis range only, set ChartExtentLink.Mode to elmOnlyX
- Now, in order to align the position of the left and right sides check the options calLeft and calRight of ChartExtentLink.AlignSides.
- Make sure that ChartExtentLink.AlignMissingAxes is checked - this creates auxiliary untitled right axes for both charts. However, there's a bug ATM which does not update the object inspector immediately; you may have to close and reload the form to see them in the object tree of the object inspector.
- Finally, select the right axis of the top chart in the object tree of the object inspector and set its Marks.Visible to true - this repeats the left axis labels on the right axis.
- Repeat with the right axis of the bottom chart.
See screenshot and attached project.