Determine when chart has changed (by clicking chart tab)

 

I have created an EA that opens several new charts using...

ChartOpen(symbol, period);

If I open 3 charts for instance, I can see the following (see attached Capture.JPG file).

When I click one of the above tabs to change chart, e.g. GBPUSD,M1, is there a way my EA can get notified of this 'chart changed' event?

As the EA is running inside a particular chart, I think this is going to require some WinAPI functionality, but that it where I get stuck :-(

Can someone please point me in the direction of a sample/solution to this issue, if possible?

Files:
Capture.JPG  12 kb
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