I am back to trying to understand web components in Dart tonight. I pick back up with last night's
pubspec.yaml with a dependency on web_ui:name: scripts dependencies: hipster_mvc: any web_ui: any unittest: anyToday it works:
➜ app git:(web-components) ✗ pub install Resolving dependencies... Downloading web_ui 0.2.10+2... Downloading logging 0.2.9+7... Downloading js 0.0.13... Downloading html5lib 0.2.2+1... Downloading args 0.2.9+7... Dependencies installed!Yesterday's woes were apparently just a result of bad replication on the Dart Pub server. It's definitely working now.
Next, I try to replace the pure Hipster MVC implementation my Dart Comics sample app. Instead, I would like to see if I can figure out web components. I start with the following
<element> template in my web page:<body>
<element name="x-hipster-collection" constructor="HipsterCollectionComponent" extends="div">
<template>
<h2>Template</h2>
<ul iterate="model in collection">
<li>{{model['title']}}</li>
</ul>
</template>
<script type="application/dart">
import 'package:web_ui/web_ui.dart';
import 'package:scripts/Collections.Comics.dart' as Collections;
class HipsterCollectionComponent extends WebComponent {
var collection = new Collections.Comics();
HipsterCollectionComponent() {
collection.fetch();
}
}
</script>
</element>
<!-- ... -->
</body>Next I add an x-hipster-collection element and try to kick start it: <div is="x-hipster-collection"></div>
<script type="application/dart">
main(){}
</script>
<script>
navigator.webkitStartDart();
</script>Internal error: Dart_Invoke: did not find top-level function 'main'.That seems odd, especially since there is quite explicitly a top-level
main() function in the HTML. If I remove the webkitStartDart() call, then I get no error, but nothing else happens either.Eventually, I read the tools article. I install the extension that is listed in that article, then try to compile my application's entry point. Unfortunately, I get a fairly lengthy stacktrace that starts with:
➜ app git:(web-components) ✗ dart --package-root=packages/ packages/web_ui/dwc.dart --out out/ web/index.html Unhandled exception: FutureUnhandledException: exception while executing Future NoSuchMethodError : method not found: 'add' Receiver: null Arguments: [" "] original stack trace: #0 Object._noSuchMethod (dart:core-patch:1360:3) #1 Object.noSuchMethod (dart:core-patch:1361:25) #2 Message.toString (file:///home/chris/repos/dart-comics/app/packages/web_ui/src/messages.dart:47:31) #3 print (dart:core-patch:1369:29) ...Stumped, I call it a night there. Hopefully I can figure out what I am doing wrong tomorrow.
Day #621
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