Basic question, duplicating a circle with javascript

[maguskrool]

Hello. I'm trying to build something like a bullseye using javascript. I'm new to scripting for Illustrator but I've used javascript before so I thought it would be simple, but maybe I'm missing some basic notions here.

I'm using Illustrator CS6. I created a blank document and drew a circle with a 1pt black stroke and no fill. Selecting that circle, I my script to copy and paste it in front and increase its radius by one centimeter. I attempted a simple duplication first:

if ( app.documents.length > 0 ) {

    var numberOfItems = 3;

    var selectedItem = app.activeDocument.selection;

    for (i=0; i < numberOfItems; i++) {

         newItem = selectedItem.duplicate();

    }

}

With my circle selected I get an error message saying "Error 24: selectedItem.duplicate() is not a function". What am I doing wrong?

Thank you in advance.

[maguskrool]

Ok, solved this one when I realized that app.activeDocument.selection returned an array of objects. So now I've got:

if ( app.documents.length > 0 ) {

    var newItem;

    var numberOfItems = 3;

    var radiusIncrease = 20;

    var selectedItem = app.activeDocument.selection[0];

    for (i=0; i < numberOfItems; i++) {

         newItem = selectedItem.duplicate();

         newItem.height += radiusIncrease;

         newItem.width += radiusIncrease;

    }

}

All I need is to convert the pixels to centimeters. Does anyone know the best way to achieve this? Thanks.

[CarlosCanto]

one way to get cm is to use the unitValue object, see a sample usage here

http://forums.adobe.com/message/4875863#4875863

[CarlosCanto]

selection returns an array, so either do either

var selectedItem = app.activeDocument.selection[0];

or

newItem = selectedItem[0].duplicate();

[pixxxelschubser]

the other way (your script):

if ( app.documents.length > 0 ) {

    var numberOfItems = 3;

    var selectedItem = app.activeDocument.selection;

    for (i=0; i < numberOfItems; i++) {

        newItem = selectedItem.duplicate();

        }

    }

[maguskrool]

Thanks. I got an error using this option, though, not sure why but it says the last item (in this case, selectedItem when i = 2) is undefined.

[pixxxelschubser]

if ( app.documents.length > 0 ) {

    var numberOfItems = 3;

    var selectedItem = app.activeDocument.selection;

    for (i=0; i < numberOfItems; i++) {

        newItem = selectedItem.duplicate();

        }

    }

maguskrool wrote:

Thanks. I got an error using this option, though, not sure why but it says the last item (in this case, selectedItem when i = 2) is undefined.

Your script says:

When (min) one document is open --> say numberOfItems = 3        //the counter is 3 --> min three or more items should be selected by yourself

selectedItem --> is the array of all selected items in document

then go for counter = 0 to counter < numberOfItems (means 3-1) -->

counter 0 = loop 1 --> duplicate this (item 1 of 3 selected) item

counter 1 = loop 2 --> duplicate this (item 2 of 3 selected) item   //when only 1 item is selected by yourself --> result is undefined

counter 2 = loop 3 --> duplicate this (item 3 of 3 selected) item   //when only 2 items are selected by yourself --> result is undefined

It's equal, how many items are selected by user - but min you have defined here --> var numberOfItems = 3; 

You need in this example a selection of three items (better: three selected items)

[maguskrool · Accepted solution]

Thanks for all the help, my code for now is:

if ( app.documents.length > 0 ) {

    var newItem;

    var numberOfItems = 3;

    var radiusIncrease = new UnitValue("1 cm").as("px");

    var selectedItem = app.activeDocument.selection;

    for (i=0; i < numberOfItems; i++) {

        newItem = selectedItem[0].duplicate();

        newItem.height += radiusIncrease;

        newItem.width += radiusIncrease;

        selectedItem[0] = newItem;

    }

}

All I need now is to center all the circles, but I haven't really delved into that yet, and if I do run into difficulties I'll start a new thread

Again, thank you.