FitAll method does not work properly when I use a Historic scale. The pens and the queries are added at runtime, the method is executed, but the command must be applied twice for proper fitting. Why is it so?
Solution:
This problem happens because FitAll method is being executed before the query has finished. In this case, you will need to add the command to E3Chart’s OnQueryFinish event, which takes place whenever one or more queries are finished in the object.
NOTE: When the event is generated, the call to FitAll or FitPen methods can cause disturbances if the automatic Query is being used, since these methods are activate other Queries until all data are read.
Another possible situation when the Historic scale is being employed is the pen not being displayed wiht all possible points, which will require executing FitAll method several times in order to show all data from the pen. This will happen exclusively due to performance issues, because the E3Chart was not developed to load all data in the DB at the same time. If AutoQuery property is on, the filters applied at E3Timestamp field will bring only the necessary data for the area displayed on E3Chart.
In this case, if the user needs FitAll to fit all points in the pen, the solution is to DISABLE the automatic query option.
The attached demo application illustrates how to add the pen and the query at run time with FitAll method at E3Chart’s OnQueryFinish event.
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