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下面的简化示例

我有 2 个视觉组件（PersonPicker 和 PersonViewer），当对象（Person）发生变化时它们需要对应。

PersonViewer 的设置器显然不会被调用，即使该组件中人员的值已更改。我需要这个，因为当人的价值发生变化时，我需要调用另一个函数（calculateSalary）。

此函数最初被正确调用，但在 PersonPicker 中更改人员时，不再调用 setter，这导致薪水标签保持初始值。

人物类

package
{
    [Bindable]
    public class Person
    {
        private var _name:String;

        public function Person()
        {
        }

        public function get name():String
        {
            return _name;
        }

        public function set name(value:String):void
        {
            _name = value;
        }

    }
}

主要应用

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" 
               xmlns:s="library://ns.adobe.com/flex/spark" 
               xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600" xmlns:local="*"
               creationComplete="creationCompleteHandler(event)">
    <s:layout>
        <s:VerticalLayout/>
    </s:layout>
    <fx:Script>
        <![CDATA[
            import mx.binding.utils.BindingUtils;
            import mx.events.FlexEvent;

            protected function creationCompleteHandler(event:FlexEvent):void
            {
                // Bind the person property of the personPicker to the person property of the personViewer
                BindingUtils.bindProperty(personViewer, "person", personPicker, "person");

                // Create a new Person and set this as the PersonPicker's person
                var john:Person = new Person();
                john.name = "John";
                personPicker.person = john;
            }

        ]]>
    </fx:Script>
    <local:PersonPicker id="personPicker"/>
    <local:PersonViewer id="personViewer"/>
</s:Application>

人物选择器

<?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" 
         width="100%" height="100">
    <fx:Script>
        <![CDATA[
            private var _person:Person;

            [Bindable]
            public function get person():Person
            {
                return _person;
            }

            public function set person(value:Person):void
            {
                _person = value;
            }

        ]]>
    </fx:Script>
    <s:DropDownList selectedItem="@{person.name}">
        <mx:ArrayCollection>
            <fx:String>Phil</fx:String>
            <fx:String>Bill</fx:String>
            <fx:String>John</fx:String>
            <fx:String>Mike</fx:String>
        </mx:ArrayCollection>
    </s:DropDownList>
</s:Group>

人员查看器

<?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" width="100%" height="100">
    <fx:Script>
        <![CDATA[
            private var _person:Person;
            [Bindable]
            public function get person():Person
            {
                return _person;
            }
            public function set person(value:Person):void
            {
                trace ("set person()");

                _person = value;

                calculateSalary();
            }

            private function calculateSalary():void
            {
                trace ("calculateSalary()");
                switch (person.name)
                {
                    case "Phil":
                        salary.text = "1000";
                        break;
                    case "Bill":
                        salary.text = "1200";
                        break;
                    case "John":
                        salary.text = "1400";
                        break;
                    case "Mike":
                        salary.text = "1600";
                }
            }
        ]]>
    </fx:Script>
    <s:layout>
        <s:HorizontalLayout/>
    </s:layout>
    <s:Label text="{person.name}"/>
    <s:Label id="salary"/>
</s:Group>

我认为这与仅更改 Person 对象的属性“名称”有关，这不会导致调用 setter。这是正确的，如果是，我该如何纠正我的例子？

4

1 回答 1

1

在PersonPicker您没有person通过在下拉列表中选择一个项目来设置属性，您只是在设置它的name.

解决此问题的一种方法是这样的（您绑定到person属性而不是它的name）：

<s:DropDownList selectedItem="@{person}" labelField="name">
    <mx:ArrayCollection>
        <m:Person name="Phil" />
        <m:Person name="Bill" />
        <m:Person name="John" />
        <m:Person name="Mike" />
    </mx:ArrayCollection>
</s:DropDownList>

此外，这里没有理由使用 BindingUtils。写吧：

<local:PersonPicker id="personPicker"/>
<local:PersonViewer id="personViewer" person="{personPicker.person}" />
于 2012-08-30T18:35:14.647 回答