dart - Observable list not updating from js Callback -

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i'm trying update template within js.callback. when cities.add("test") main() works fine , updates template string, doing same within callback template not updating. i'm trying use javascript api parse.com. login works , getting objects querys well. started out learning dart, maybe it's obvious i'm missing?

update: problem solved calling js.retain(parse) , dispatch() working solution below.

mydart.html :

<template iterate="city in cities"> {{city}} </template>

mydart.dart :

import 'dart:html'; import 'package:web_ui/web_ui.dart'; import 'package:js/js.dart' js;  var parse = js.context.parse;  list<string> cities = new list();  void main() {    js.retain(parse); //solution problem (1/2)    parse.initialize("id", "key");    if(parse.user.current() == null) {      parse.user.login("user", "password",         js.map({           "success": new js.callback.once((user) => parsedata()),           "error": new js.callback.once((user,error) => print(error.message))         })     );   }   else     parsedata();    cities.add("hej"); }  void parsedata() {    //get cities   var city = parse.object.extend("city");   var query = new js.proxy(parse.query, city);   query.equalto(js.map({"acl" : parse.user.current()}));    query.find(     js.map({       "success": new js.callback.once((array){           (var i=0; < array.length; i++){           string cityname = array[i].get("name");           cities.add(cityname);           dispatch(); //solution problem (2/2)         }       }),       "error": new js.callback.once((object,error) => print(error.message))     })       ); }

there seems 2 problems code :

  • you should call watcher.dispatch() after having updated list through callback.
  • the top level variable parse js.proxy used in callback. proxy has retained (with js.retain(parse)) used outside of current eventloop otherwise error js ref has been invalidated.

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