Retrieve Values Only if Interval() or Name() has changed

AFL Programming
1

Dear Sirs,

I need to Retrieve some Array Values from an ODBC Data source for plotting on chart.
For the sake of conserving resources I wish to Retrieve/Refresh Values Only if Interval() or Name() has changed.

For that purpose I am using the following code:

if( Name() != VarGetText( "SYMBOL_XYZ" ) OR Interval(2) != VarGetText( "Interval_XYZ" ) )
{
    VarSetText( "SYMBOL_XYZ", Name() );
    VarSetText( "Interval_XYZ", Interval(2) );
    VarSetText( "mNOW" , Now( 2 ) );
    // Retrieve Values from ODBC Source
}

Title = VarGetText( "mNOW") ;
Plot( C, "Close", ParamColor("Color", colorDefault ), styleNoTitle | ParamStyle("Style") | GetPriceStyle() );

In this sample code, I expect the Title to update only on change in Interval() or Name() -
It should not change on chart scrolls, Zooms or simple clicks etc.

However, the title is changing even on Simple clicks on chart.
{Incidentally the AFL is going to be used on a Layout with Multiple charts, with multiple Intervals (Sharing same chart_ID ) }

It will be very nice if the Seniors please guide about what should be corrected in the AFL.

With Thanks and Regards

Sanjiv Bansal

2

First you should use static variables (staticvarset) because only static variables keep vales between executions

1 Like
3

Dear Sir,

Thank you very much for your guidance.
My initial code was also using Static Variables,
However, the StaticVariables that I was creating were composites of Name() and Interval().
And these Composite StaticVariables were not compatible with MultiChart Multi_Interval Layouts.

Now, I have removed Interval() from my Text StaticVariables and things seem to be progressing in desired direction.

Thank you again for your guidance and Nice Software.

With Regards

Sanjiv Bansal