使用@published设置bool已发布的属性 [英] Setting a bool published attribute with @published

问题描述

我有以下.dart组件

I have the following .dart component

@CustomTag('description-form')
class DescriptionForm extends PolymerElement {
  @observable Map<String, dynamic> datamap = {};
  @observable String description = '';

  @published
  String get label => readValue(#label);
  set label(String value) => writeValue(#label, value);

  @published
  bool get isVisible => readValue(#isVisible);
  set isVisible(bool value) => writeValue(#isVisible, value);

  DescriptionForm.created() : super.created();

  void publish() {
    datamap['description'] = description;
  }

  @override
  void attached() {
    super.attached();
    datamap['receiver'] = dataset['receiver'];
  }
}

要使用已发布的属性，我将执行以下操作

To use the published attributes, I would do the following in a form

  <description-form
    label = 'Others'
    isVisible = false
    data-receiver = 'shared| description-form --> dynamic-chkbx'>
  </description-form>

当标签解析时，isVisible不会。
设置使用 @published ？

While label is resolved, isVisible does not. What is the correct mechanism to set a bool that is published using @published?

推荐答案

通常，布尔属性的工作原理是基于它们是否存在。因此，如果您在类中设置属性，像这样：

Typically, boolean attributes work based on whether they're present or not present. So if you set up the property in your class like so:

@PublishedProperty(reflect: true) bool isVisible = true;

然后，您可以在HTML中使用它：

Then you can use it in the HTML like this:

  <description-form
    label = 'Others'
    isVisible
    data-receiver = 'shared| description-form --> dynamic-chkbx'>
  </description-form>

当标签上出现 isVisible 它在类中的 true ，并将类的属性更改为 false 删除标记上的属性

When isVisible is present on the tag, it's true in the class, and changing the class's property to false removes the attribute on the tag (thanks to reflect: true).

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