Re: ChartDemo problem 2: Storing and retrieving component data not defined as published fields

Author

Message

Sergey Tkachenko

Posted: 08/30/2002 15:59:59

Yes, it looks like TChart does not save its data.

But in your component you can create properties and "pseudo-properties" with

your own procedures for reading and writing.

I've attached a simple example of component - grid that can save its cells

in DFM (and RVF).

For arbitrary data, use Filer.DefineBinaryProperty instead of

Filer.DefineProperty.

> My second problem is not related to printing but interresting anyway, at

least

> to me... :-)

> Is there an "official" RV way to handle the situation when the components

> are containing data not related to a published field. (I guess that's the

> case in the TChart demo: When saving the demo page containing the

data-filled

> charts and loading it back, the data is gone...)

> My own solution is adding a persistent stream to the component, and saving

> the data to this one BEFORE saving the rvf, and later reading the data

back

> from the persistent stream for each component AFTER the rvf is loaded.

> Is there a simpler way? Would it be possible to extend the demo whith this

> kind of "saving and loading charts pages containing chart

data"-functionality?

> Reagards, and thanks for a superb product! / Jonas

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end