由网友(暖神小阿哥。)分享简介：我发现这是非常有用的特殊情况下，在下拉菜单（菜单即实例）的第一个项目。举例来说，如果我想选择由Web服务提供的列表中选择颜色：＆LT; MX：PopUpMenuButton等ID =colorSelelector的dataProvider ={colorsService.lastResult}/＆GT;我也可能需要一个...

我发现这是非常有用的特殊情况下，在下拉菜单（菜单即实例）的第一个项目。举例来说，如果我想选择由Web服务提供的列表中选择颜色：

 ＆LT; MX：PopUpMenuButton等ID =colorSelelector
    的dataProvider ={colorsService.lastResult}/＆GT;
 

我也可能需要一个特殊情况，这是进入一个新的颜色，允许用户输入的RGB值的新彩色这不是在该列表中。例如：

  VAR newColor = {标签：进入一个新的色彩，RGB：空};
 

然后用

 ＆LT; MX：PopUpMenuButton等ID =colorSelelector
    的dataProvider ={colorsService.lastResult}
    lastOption ={newColor}/＆GT;
 

那么，除了改变列表中我得到的服务回报，有没有更好的方式来做到这一点？

（和仅preemptive评论：这是一个简化的......我没有真正试图使一个颜色采摘列表）

解决方案   

那么，除了改变列表中我得到   从服务背后，是有什么   更好的方式来做到这一点？

此方法将是最干净的，不延长的HTTPService，这将很好地工作（但实际上只是改变你的结果;））：

 包
{
    进口mx.rpc.http.HTTPService;

    公共类MyHTTPService扩展的HTTPService
    {
    公共变种appendToResult：对象;

    公共职能MyHTTPService（则rootURL：字符串=空，目标：字符串= NULL）
    {
    超（则rootURL，目的地）;
    }

        [可绑定（resultForBinding）]
        重写公共职能得到的lastResult（）：对象
        {
        //我知道我的类型，数组作为一个例子
        VAR myResult中：数组= operation.lastResult;
        myResult.push（this.appendToResult）
            返回myResult中;
        }
    }
}
 

I've found it's often useful to special case the first item in a drop-down menu (ie, an instance of Menu). For example, if I want to pick a color from the list provided by a web service:

<mx:PopUpMenuButton id="colorSelelector"
    dataProvider="{colorsService.lastResult}" />

I might also want a special-case, which is "enter a new color", allowing the user to enter the RGB values for a new color which isn't in the list. For example:

var newColor = { label: "Enter a new color", rgb: null };

Then used with:

<mx:PopUpMenuButton id="colorSelelector"
    dataProvider="{colorsService.lastResult}"
    lastOption="{newColor}" />

So, apart from changing the list I get back from the service, is there any better way to do this?

(and just a preemptive comment: this is a simplification… I'm not actually trying to make a color-picking-list)

解决方案

So, apart from changing the list I get back from the service, is there any better way to do this?

This approach is going to be the cleanest, without extending HTTPService, which would work well (but is really just altering your result ;) ):

package
{
    import mx.rpc.http.HTTPService;

    public class MyHTTPService extends HTTPService
    {
    	public var appendToResult:Object;

    	public function MyHTTPService(rootURL:String=null, destination:String=null)
    	{
    		super(rootURL, destination);
    	}

        [Bindable("resultForBinding")]
        override public function get lastResult():Object
        {
        	//I know what my type is, Array as an example
        	var myResult:Array = operation.lastResult;
        	myResult.push( this.appendToResult )
            return myResult;
        }
    }
}