更新一个 var，它从另一个组件中获取它的值 [英] Update a var, which get's it it's value from another component

问题描述

我在更新 var 并在创建完成时使用它触发函数时遇到问题.

I'm having trouble with updating a var and firing a function with it on creationcomplete.

在主要组件中，我声明了一个 var 艺术家.这个 var 肯定有效并且有价值.我还需要另一个组件中的 var:一个配置文件组件.我可以通过以下方式获得该变量:

In the main component i declared a var artist. This var certainly works and has a value. I also need that var in another component: a profile component. I am able to get that var with:

newVar = Maincomp(this.parentApplication).artist; 

我在配置文件组件的 API 中使用了 newVar.当我使用 mouseEvent 启动 API 函数时，它可以工作.但是，我想在 creationComplete 上启动 API 函数，而 var 不起作用:它返回 Null.我希望使所有涉及的变量都可绑定会有所帮助，但事实并非如此.如何解决这个问题?

I use the newVar in an API in the profile component. When i launch the API function with a mouseEvent, it works. However, i want to launch the API function on creationComplete and than the var doesn't work: it returns Null. I hoped that making all the involved vars bindable would help, but it doesn't. How can this be fixed?

使我的案例更清晰的额外代码:

Extra code to make my case clearer:

在主曲中:

        public function handleclick(cName:String):void
        {
            vName = "aVariableIGetFromAnAPI";
        }

在配置文件中:

                    public function zoekImages(event:FlexEvent):void
        {
            var api_URL:String = 'http://ws.audioscrobbler.com/2.0/';
            var api_imagemethod:String = 'artist.getImages';
            var api_key:String = '99f1f497c0bd598f1ec20571a38e2219';
            artistImage = DifficultierAPI(this.parentApplication).vName;
            var autocorrect:String = '1';
            var limit:String = '4'; 
            api_imagerequest = api_URL + '?method=' + api_imagemethod  + '&artist=' + artistImage + '&autocorrect=' + autocorrect + '&api_key=' + api_key + '&limit=' + limit;
            imageRequest.send(); // hier maak je connectie met lastfm
        }

此代码有效，但重点是，如果我使用 MouseEvent 调用此代码，则此代码有效，但在创建完成时需要启动时无效.或者，它返回 Null 而不是值.我认为使涉及的变量可绑定会解决它，但事实并非如此.有什么帮助吗?

This code works, but point is that this code works if i call it with a MouseEvent, but doesn't when it needs to launch on creationcomplete. Or well, it returns Null instead of a value. I thought that making the involved vars bindable would fix it, but it doesn't. Any help?

推荐答案

如果您希望将变量从主应用程序一直绑定到嵌套组件，只需在您的组件中将变量声明为 public 且可绑定:

If you're looking to bind the variable all along from the main application to the nested component, simply declare a variable as public and bindable within your component :

主要应用

<?xml version="1.0" encoding="utf-8"?>
<s:WindowedApplication xmlns:fx="http://ns.adobe.com/mxml/2009" 
    xmlns:s="library://ns.adobe.com/flex/spark" 
    xmlns:mx="library://ns.adobe.com/flex/mx" xmlns:Components="Components.*">

    <fx:Script>
        <![CDATA[
            [Bindable]
            public var myMainVar:String;

            protected function button1_clickHandler(event:MouseEvent):void
            {
                myMainVar = "Hi there!";
            }

        ]]>
    </fx:Script>

    <s:layout>
        <s:VerticalLayout/>
    </s:layout>

    <s:Button label="Click me to update the coponent's variable" click="button1_clickHandler(event)"/>

    <Components:MyCustomComponent myComponentVar="{myMainVar}"/>

</s:WindowedApplication>

嵌套组件

<?xml version="1.0" encoding="utf-8"?>
<s:Group xmlns:fx="http://ns.adobe.com/mxml/2009" 
    xmlns:s="library://ns.adobe.com/flex/spark" 
    xmlns:mx="library://ns.adobe.com/flex/mx">

    <fx:Script>
        <![CDATA[
            [Bindable]
            public var myComponentVar:String;
        ]]>
    </fx:Script>

    <s:Label text="{myComponentVar}"/>

</s:Group>

我希望这就是你要找的 :-)

I hope it is what you're looking for :-)

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