通过飞镖代码实现聚合物元素 [英] Instantiating polymer element via dart code

问题描述

我试图在我的Dart代码中实例化一个 Polymer 元素。

/ p>

  @CustomTag（'card-component'）
类CardComponent extends PolymerElement {
 @published 
 String playerName; 
 
 CardComponent.created（）：super.created（）;到目前为止，我发现要工作的唯一方法是：
 
} 
  

$ b <

 元素y = new Element.tag（'card-component'）; 
  

但我真正想做的是通过访问器访问我的组件的值（而不是 HtmlElement 的属性）。有没有办法直接在Dart中实例化 CardComponent ，而不使用 Element.tag 方式？我尝试以多种方式使用 CardComponent.created（）方法，但它没有工作。

case你想知道为什么我想这样做，我想传递参数到我的构造函数，甚至使用工厂来创建一个理想的世界中的组件。

编辑：阅读这个答案后，我最终能够做到我想要的。我只需要这个到我的组件

  factory CardComponent（String playerName）=> document.createElement（card-component）
 ..attributes = {
playerName：playerName 
}; 
  

然后实例化为：

  CardComponent myNewCard = new CardComponent（Pacane）; 
  

解决方案

我不知道通过访问器访问我的组件的值（而不是 HtmlElement 的属性）

 （new Element.tag（'card-component'）as CardComponent）
 ..playerName ='blabla'; 
 

添加自定义工厂构造函数允许您像使用正常构造函数一样使用元素



class CardComponent extends PolymerElement {
（$ card $）


@published
String playerName;

CardComponent.created（）：super.created（）;

factory CardComponent CardComponent（）{
return new Element.tag（'card-component'）;
}
}


  var cc = new CardComponent（）.. playerName ='blabla'; 
  

如果你想从 main（）不是来自另一个组件，请确保 main（）包含Polymer（初始化代码为什么我在polymer.dart元素上遇到类型错误？，如何在聚合物应用程序中实现主要功能） / p>

I'm trying to instantiate a Polymer element in my Dart code.

Here's my element:

@CustomTag('card-component')
class CardComponent extends PolymerElement {
  @published
  String playerName;

  CardComponent.created() : super.created();
}

So far the only way I found to be working was:

Element y = new Element.tag('card-component');

But what I would really like to do, would be to access the values of my component by their accessors (instead of by attributes of HtmlElement). Is there a way to instantiate a CardComponent directly in Dart without using the Element.tag way? I tried using the CardComponent.created() method in multiple ways but it didn't work either.

In case you wonder why I want to do this, well I would like to pass parameters to my constructor, or even use a factory to create the component in an ideal world.

Edit: After reading this answer I ended up being able to do what I wanted. I just had to had this to my component

factory CardComponent(String playerName) => document.createElement("card-component")
  ..attributes = {
    "playerName" : playerName
};

And then instantiate it like this:

CardComponent myNewCard = new CardComponent("Pacane");

解决方案

I don't know what exactly you mean by "to access the values of my component by their accessors (instead of by attributes of HtmlElement)"

(new Element.tag('card-component') as CardComponent)
    ..playerName = 'blabla';

adding a custom factory constructor allows you to use the element as if it had a normal constructor

@CustomTag('card-component')
class CardComponent extends PolymerElement {
  @published
  String playerName;

  CardComponent.created() : super.created();

  factory CardComponent CardComponent() {
    return new Element.tag('card-component');
  }
}

var cc = new CardComponent()..playerName = 'blabla';

If you want to do this from main() not from within another component, ensure that main() contains the Polymer (initialization code why am I getting type error on polymer.dart element?, how to implement a main function in polymer apps)

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