I wanna get callback as an array object from jsx to PS html panel

[Kawano Shuji]

I`ve developed a Photoshop extension and I try to get callback from jsx

for example

JS

function init() {

        var csInterface = new CSInterface();       

        themeManager.init();

        $("#btn_test").click(function () {

            csInterface.evalScript('getstatus()',function(f){

       alert(f);     //value is 1,2,3            looks array object but Data Type is String

            });

        });

}

JSX

function getstatus(){

var f =[1,2,3];

return f;   

    }

getstatus  return array object but it became String object when evalScript get callback

It`s very inconvenience 

if someone give me good idea I would be glad

Shuji

[Davide_Barranca · Accepted solution]

Hi,You

you need to include json2.js in the JSX, for ExtendScript doesn't know about JSON natively.

Then in the JS:

$('#arr').on('click', function(){
    csInterface.evalScript('getArray()', function(res){
        console.log(JSON.parse(res));
    })
})

and in the JSX:

function getArray() {
  return JSON.stringify([1,2,3]);
}

You may want to have a look at my HTML Panel Tips series to get a headstart with similar matters.

Hope this helps!

Cheers,

Davide

[Marc Autret]

Hi Davide,

It should be noted that Crockford's json2.js is not fully ExtendScript compliant. (More precisely, ExtendScript is not fully ECMA compliant, as you already know.)

In particular, json2 uses a few ternary operations in the form

cond1 ? "cond1 OK" : cond2 ? "cond2 OK" : "cond2 KO"

assuming right-associativity of the ternary op, which is the case in ECMA-262 but not in ExtendScript 😕

Studying json2 some months ago I found other tricky issues, which leads me to implement IdExtenso's JSON module:

IdExtenso/$$.JSON.jsxlib at master · indiscripts/IdExtenso · GitHub

Best,

Marc

[Davide_Barranca]

Thank you Marc!

Isn't your JSON implementation plug-and-play replacement of json2.js, correct?

[Marc Autret]

Hi Davide,

Indeed my JSON module requires the framework (IdExtenso), which by definition involves InDesign.

Maybe I should provide adapters for other ExtendScript hosts, but ID remains my main scope (so far.)

However, 99% of the code is purely ExtendScript-based, so it wouldn't be too difficult to extract an universal JSON.jsx from it…

@+

Marc

[Marc Autret]

I finally did it:

extendscript/JSON at master · indiscripts/extendscript · GitHub

Hope that helps,

Marc

[Trevor:]

Well done Marc!

Brilliant and incredibly useful code.

I just want to point out (not to you!) the obj.toSource() method.

Given Marc's test object

var obj = {
    myNumber: 12345678,
    myBool: true,
    myString: "Hello\tWorld\u00a0: This is fine!",
    myRegex: /[a-z\d]+/,
    myArray: [ ['this', 'is'], [1], ['array', 'of', 'arrays'] ],
    myObject: {a:1,b:2,c:3},
    myUnit: UnitValue(5,'mm'),
    myXML: <root><aaa xxx='yyy'>hello</aaa></root>,
    myDate: new Date,
    myFile: File("c:/test.txt"),
    myNativeObj: $.global,
};

His code will produce

{
    "myNumber" : 12345678,
        "myBool" : true,
        "myString" : "Hello\tWorld\xA0: This is fine!",
        "myRegex" : RegExp("[a-z\\d]+",""),
        "myArray" : [
            [ "this", "is" ],
                [ 1 ],
                [ "array", "of", "arrays" ]
            ],
        "myObject" : {
                "a" : 1,
                "b" : 2,
                "c" : 3
            },
        "myUnit" : UnitValue("5mm"),
        "myXML" : <root>
      <aaa xxx="yyy">hello</aaa>
      </root>,
    "myDate" : (new Date(1508054575699)),
        "myFile" : File("/c/test.txt"),
        "myNativeObj" : $.global
    }

This is so to speak a "perfect"* result. If one only needs to parse more simple objects / arrays then obj.toSource() could well do. See how obj.toSource() passes and fails Marc's test object

({
        myNumber: 12345678,
        myBool: true,
        myString: "Hello    World : This is fine!",
        myRegex: (new RegExp(/[a-z\d]+/)),
        myArray: [
            ["this", "is"],
                [1],
                ["array", "of", "arrays"]
            ],
        myObject: { a: 1, b: 2, c: 3 },
        myUnit: ({}),
        myXML: ({}),
        myDate: (new Date(1508054393407)),
        myFile: new File("/c/test.txt"),
        myNativeObj: ({})
    })

If the passes are good enough and the fails are irrelevant to you then it's going to be the simplest method of passing.

*Marc's result is "perfect" for the JSX engine for which it was written but the results are going to have to be treated with great care on the JS end of the extension.

In particular the xml and native objects like the UnitValue and $.global are going to cause a parsing error if just blindly parsed.

Ten A​ It is true that Photoshop will automatically parse the callback as a string as will as far as I know all the apps with the noted exception of InDesign. If the result is not explicitly made a string on the JSX engine then the JS engine just receives a blank callback.

One other note, one from CEP6.1 parse the object directly from the JSX engine to JS engine as an object that does not need parsing if using the PlugPlug and CSXSEvent(); methods and then on the JS side you receive it as using addEventListener This method is a bit less convenient than the standard callback method but save the need for the JSON.parse on the other end.

[Kawano Shuji]

Hi Davide,

thank you for reply me
I tried to it
It was success , I got value as an Array object

this is very useful

Shuji

[Ten A]

ExtendScript function always return String, we need to parse it as David say.

[Kawano Shuji]

I didn't know that ExtendScript always return String
I tried to it without Json2 many time