fixes error thrown when using charts in page- or tabview

[jplekkerkerker]

As mentioned in #277 the BaseChartState throws an error when skipping over in a page- or tabview. I've implemented the check as mentioned in the pull request and that fixes the problem.

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[jplekkerkerker]

@googlebot I signed it!

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[92Andy]

This is looking good!

[92Andy]

Apparently someone is needed who has the necessary write access. Can someone approve this fix please?

[winksaville]

There is a fork of charts at exafree/charts_cf that accepts pull requests.

[yemlihaoner]

this solved our memory leak bug on dispose()

[stuartmorgan]

This project is no longer maintained, and cannot accept any PRs. Community members interested in collaborating on a community-maintained fork can coordinate in this issue.