Processing Javascript Promises in Java

[aghasemi]

Hi,

Is there an example of how to process the return value of a native function when it is a Promise?

To begin with, I had to add teavm-core to my dependencies so that I could have the Promise class (it wasn't added by the archetype).

Promise is not a subclass of JSObject. When I ran the following code:

Promise p =  callModule().cast();
p.then( obj -> {
            System.out.println(obj);
            System.out.println(obj.getClass());
            return null;
});

I got Uncaught TypeError: ia_Client_callModule$js_body$_1(...).$then is not a function. If I print the output object of callModule, it is [object Promise]. Is there an extra step required?

Thanks Best

[konsoletyper]

Promises declared in core module have nothing to do with JavaScript Promise class. There's no standard wrapper declared for Promise, so you need to write your own definition.

[tryone144]

https://github.com/konsoletyper/teavm/pull/884 introduced JSPromise as an interface for native promises. This should cover the above use-case.