why setbar did not work as I expected

[clearpicks]

I am trying to use setBar() to change the indicator values of previous 50 bars when getCurrentBarIndex() == -20, however it seems setBar() did not work as I expected. I am expecting the test script shows a black line segment between bar -21 and -70, what was wrong?

- Clearpicks

var returnArray;
function preMain()
{
setPriceStudy(true);
setStudyTitle("TestSetBar");
}

function main()
{
if ( getBarState() == BARSTATE_ALLBARS ) {
returnArray = new Array(1);
returnArray[0] = close(0);
setDefaultBarThickness(4, 0);
setDefaultBarStyle(PS_DASH, 0);
setPlotType(PLOTTYPE_FLATLINES, 0);
setDefaultBarFgColor(Color.lime, 0);
}
if ( getCurrentBarIndex() == -20 ) {
var highColor = Color.RGB(255, 153, 0);
returnArray[1] = close(0);
setDefaultBarThickness(4, 1);
setDefaultBarStyle(PS_DASH, 1);
setPlotType(PLOTTYPE_FLATLINES, 1);
setDefaultBarFgColor(highColor, 1);

var j;
for ( j = 1; j < 50; j ++ ) {
setBar(Bar.Value, -j, 1, returnArray[1] );
setBar(Bar.FgColor, -j, 1, Color.black );
setBar(Bar.Thickness, -j, 1, 4 );
setBar(Bar.Style, -j, 1, PLOTTYPE_FLATLINES );
}
}

return returnArray;
}

[ACM]

Re: why setbar did not work as I expected

clearpicks
You are setting the array length incorrectly ie
returnArray = new Array(1);
whereas it should be
returnArray = new Array(2);
Once you change that it will work as intended (see screenshot)
Alex

Originally posted by clearpicks
I am trying to use setBar() to change the indicator values of previous 50 bars when getCurrentBarIndex() == -20, however it seems setBar() did not work as I expected. I am expecting the test script shows a black line segment between bar -21 and -70, what was wrong?

- Clearpicks

var returnArray;
function preMain()
{
setPriceStudy(true);
setStudyTitle("TestSetBar");
}

function main()
{
if ( getBarState() == BARSTATE_ALLBARS ) {
returnArray = new Array(1);
returnArray[0] = close(0);
setDefaultBarThickness(4, 0);
setDefaultBarStyle(PS_DASH, 0);
setPlotType(PLOTTYPE_FLATLINES, 0);
setDefaultBarFgColor(Color.lime, 0);
}
if ( getCurrentBarIndex() == -20 ) {
var highColor = Color.RGB(255, 153, 0);
returnArray[1] = close(0);
setDefaultBarThickness(4, 1);
setDefaultBarStyle(PS_DASH, 1);
setPlotType(PLOTTYPE_FLATLINES, 1);
setDefaultBarFgColor(highColor, 1);

var j;
for ( j = 1; j < 50; j ++ ) {
setBar(Bar.Value, -j, 1, returnArray[1] );
setBar(Bar.FgColor, -j, 1, Color.black );
setBar(Bar.Thickness, -j, 1, 4 );
setBar(Bar.Style, -j, 1, PLOTTYPE_FLATLINES );
}
}

return returnArray;
}

[clearpicks]

Does it mean the number of indicator lines has to be determined before the first time returnArray is returned?

[ACM]

clearpicks
To my knowledge you need to return an array of the appropriate length to use setBar() to adjust the value and/or properties of any returned item beyond the first one. In your script the returned array has a length of 1 up to bar index -20 so prior to that bar index you can't adjust the properties of its 2nd element as it does not exist
Alex

Originally posted by clearpicks
Does it mean the number of indicator lines has to be determined before the first time returnArray is returned?