我想通过其他自定义元素(localized_element)来更新属性标签在自定义元素(signin_element)。但在操作过程中,物业标签已将地图类型更改为字符串。DART POLYMER:我如何从另一个自定义元素更新属性?
说明:
1 /就在应用程序启动后,自定义元素(登入元素)更新属性标签与地图(查看文件signin.dart)。
2 /自定义元素本地化元素后初始化,物业标签与来自外部的JSON文件的新地图更新。方法更新无法将新的Map分配给属性标签,因为现在是字符串。
铬回报警告:
Attributes on signin-element were data bound prior to Polymer upgrading the element. This may result in incorrect binding types.
Attributes on localized-element were data bound prior to Polymer upgrading the element. This may result in incorrect binding types.
最后返回一个错误:
Class 'String' has no instance method '[]='.
Signin.html:
<core-animated-pages selectedindex="0" notap id="core_animated_pages">
<section id="section1" layout horizontal active center-justified center>
<core-card id="core_card" layout vertical>
<paper-input label="Your email addres" floatinglabel id="email_input"></paper-input>
<paper-input label="Your password" floatinglabel id="password_input"></paper-input>
<div id="div" layout horizontal end-justified>
<paper-fab icon="check" id="paper_fab"></paper-fab>
</div>
<h2>{{labels['hello']}}</h2>
</core-card>
</section>
</core_animated_pages>
<localized-element id="l10n" locale={{locale}} labels={{labels}}></localized-element>
signin.dart
@CustomTag('signin-element')
class Signin extends PolymerElement {
@published String locale = 'en';
@observable Map labels = toObservable({
'hello': 'Hello 1'
});
Signin.created() : super.created();
}
localized.dart
@CustomTag('localized-element')
class Localized extends PolymerElement {
@published String locale = 'en';
@published Map labels;
Localized.created() : super.created();
ready() {
super.ready();
_loadTranslations();
}
update() {
if (!_l10n.containsKey(locale)) return;
var l10n = _l10n[locale];
labels['hello'] = l10n['hello'];
}
List locales = ['en', 'fr'];
_loadTranslations() {
locales.forEach((l10n)=> _loadLocale(l10n));
}
Map _l10n = {};
_loadLocale(_l) {
HttpRequest.getString('i18n/translation_${_l}.json')
.then((res) {
_l10n[_l] = JSON.decode(res);
update();
})
.catchError((Error error) {
print(error.toString());
});
}
}
冈特您好,感谢再次帮助我:)。我想你说的是PublishedProperty而不是PublishedAttribute的权利?如果是的话,问题总是一样的。我无法使用新的Map更新标签,因为该类型是一个字符串。 – olituks
你能发布一个可以在GitHub上重现问题的工作示例吗?感谢提示,我更新了答案。 –
声音:https://drive.google.com/file/d/0B7kQatBvjEOzMTVFN1ZZeEdab3c/edit?usp=sharing要保存完整的zip文件,您可以使用文件 - >下载 – olituks