我是灵活开发的新手。我有一个动态数据绑定列表组件。我需要限制用户选择超过5个项目。
列表是使用复选框和标签
getSelectionCount()方法返回当前所选项目的数量。
这是我的代码
<s:VGroup width="100%" height="100%">
<s:List id="chkLst" visible="{isMultipleSelectionAllowed}" width="100%" height="100%" borderVisible="false"
fontFamily="segoeui"
dataProvider="{filteredDataSet}" >
<s:itemRenderer>
<fx:Component>
<s:ItemRenderer>
<fx:Script>
<![CDATA[
import mx.controls.Alert;
//-----------------------------------------------
//
// Checkbox select
//
//-----------------------------------------------
protected function chk_clickHandler(event:MouseEvent):void
{
var selection:Array = new Array();
for each(var item:Object in outerDocument.chkLst.dataProvider)
{
selection.push(item);
}
var count:int = 0;
for each(var sItem:Object in selection)
{
outerDocument.setSelectionCount(0);
if(sItem.selected)
{
count++;
}
outerDocument.setSelectionCount(count);
}
Alert.show(outerDocument.getSelectionCount()+"","test");
if(CheckBox(event.target).selected && outerDocument.getSelectionCount() <= 5){
outerDocument.setSelectionCount(outerDocument.getSelectionCount()+1);
}
if(outerDocument.getSelectionCount() >= 6){
}
}
]]>
</fx:Script>
<s:HGroup width="100%" height="30" gap="2" paddingLeft="5" paddingRight="5" verticalAlign="middle" clipAndEnableScrolling="true">
<s:CheckBox id="chk"
label="{data.label}" change="{data.selected = chk.selected}" selected="{data.selected}"
maxWidth="215" click="chk_clickHandler(event)" />
</s:HGroup>
</s:ItemRenderer>
</fx:Component>
</s:itemRenderer>
</s:List>
2如果用户取消某些检查以便选择计数低于5,我还需要启用所有复选框
谢谢
答案 0 :(得分:1)
首先,您需要在arraycollection中添加enabled
属性,如下所示,itemRenderer make bindable
中也enabled="{data.enabled}"
。如果count达到5,我们禁用所有按钮,除了选中的按钮,启用属性和魔法的帮助我们需要使用mx.collections.IList.itemUpdated(item:Object, property:Object=null, oldValue:Object=null, newValue:Object=null):void
方法更新arraycollection项目,这样只有它会反映禁用其他复选框。在我们的例子中使用outerDocument.chkLst.dataProvider.itemUpdated(item);
示例arraycollection结构:
<fx:Declarations>
<s:ArrayCollection id="filteredDataSet" >
<fx:Object selected="false" enabled="true" label="one"/>
<fx:Object selected="true" enabled="true" label="two"/>
<fx:Object selected="false" enabled="true" label="three"/>
<fx:Object selected="false" enabled="true" label="four"/>
<fx:Object selected="false" enabled="true" label="five"/>
<fx:Object selected="false" enabled="true" label="six"/>
<fx:Object selected="false" enabled="true" label="seven"/>
<fx:Object selected="false" enabled="true" label="eight"/>
<fx:Object selected="false" enabled="true" label="nine"/>
</s:ArrayCollection>
</fx:Declarations>
<s:List id="chkLst" width="100%" height="100%" borderVisible="false"
fontFamily="segoeui"
dataProvider="{filteredDataSet}" >
<s:itemRenderer>
<fx:Component>
<s:ItemRenderer>
<fx:Script>
<![CDATA[
import mx.controls.Alert;
protected function chk_clickHandler(event:MouseEvent):void
{
data.selected = chk.selected;
var selection:Array = [];
for each(var item:Object in outerDocument.chkLst.dataProvider)
{
if(item.selected)
selection.push(item);
}
if(selection.length>=5)
{
for each(var item:Object in outerDocument.chkLst.dataProvider){
item.enabled = item.selected;
outerDocument.chkLst.dataProvider.itemUpdated(item);
}
}else{
for each(var item:Object in outerDocument.chkLst.dataProvider){
item.enabled = true;
outerDocument.chkLst.dataProvider.itemUpdated(item);
}
}
}
]]>
</fx:Script>
<s:HGroup width="100%" height="30" gap="2" paddingLeft="5" paddingRight="5" verticalAlign="middle" clipAndEnableScrolling="true">
<s:CheckBox id="chk" label="{data.label}" selected="{data.selected}" enabled="{data.enabled}"
maxWidth="215" click="chk_clickHandler(event)" />
</s:HGroup>
</s:ItemRenderer>
</fx:Component>
</s:itemRenderer>
</s:List>