我正在尝试将搜索字段添加到Adobe Flex项目中，当您键入新创建的搜索字段时，我收到以下错误：
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at flextest/filterDecalMyArrayCollection()
at mx.collections::ListCollectionView/internalRefresh()
at mx.collections::ListCollectionView/refresh()
at flextest/filterDecal()
at flextest/__searchDecal_change()
at flash.events::EventDispatcher/dispatchEventFunction()
at flash.events::EventDispatcher/dispatchEvent()
at mx.core::UIComponent/dispatchEvent()
at mx.controls::TextInput/textField_changeHandler()
非常感谢任何帮助！
以下是我在Flex项目中的代码：
<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
initialize="doSend()"
layout="absolute" width="1092" height="834">
<mx:Style source="flextest.css"/>
<mx:Script>
<![CDATA[
import mx.collections.ArrayCollection;
import mx.events.ListEvent;
import mx.rpc.events.FaultEvent;
import mx.rpc.events.ResultEvent;
import mx.rpc.http.HTTPService;
[Bindable]
private var datalist:ArrayCollection;
private var rowcount;
private var firstTimeID:Boolean = true;
private var firstTimeName:Boolean = true;
private var firstTimeDL:Boolean = true;
private var firstTimeDecal:Boolean = true;
private var firstTimeTag:Boolean = true;
private function resultHandler(event:ResultEvent):void{
datalist = event.result.data.row;
rowcount = event.result.data.numrows;
/* if(rowcount == '1'){
datalist.removeItemAt(1); */
}
public function doSend():void {
xmlFromDatabase.url = "http://webprod.jsu.edu/pd/guestxml.php?t=" + new Date().getTime();
xmlFromDatabase.send();
}
private function onItemClick( e:ListEvent ):void {
var dlAdjust;
txtTuid.text = e.itemRenderer.data.TUID;
txtStudentName.text = e.itemRenderer.data.STUDENTNAME;
txtDecalYear.text = e.itemRenderer.data.DECALYEAR;
txtDecalType.text = e.itemRenderer.data.DECALTYPE;
txtConfNo.text = e.itemRenderer.data.DECALNUMBER;
txtDecNo.text = e.itemRenderer.data.DECALNUMPERM;
if (e.itemRenderer.data.DECALCAT == "WHIT") {
cmbCategory.selectedIndex = 0;
} else {
cmbCategory.selectedIndex = -1;
}
txtOriginalDate.text = e.itemRenderer.data.ORIGDATE;
txtUpdateDate.text = e.itemRenderer.data.UPDTDATE;
txtNote.text = e.itemRenderer.data.DECALNOTES;
dlAdjust = e.itemRenderer.data.DLNUM;
txtDLic.text = dlAdjust.slice(0, dlAdjust.length - 2);
txtDLState.text = e.itemRenderer.data.DLSTATE;
txtVMake.text = e.itemRenderer.data.VMAKE;
txtVModel.text = e.itemRenderer.data.VMODEL;
txtVBody.text = e.itemRenderer.data.VBODY;
txtVColor.text = e.itemRenderer.data.VCOLOR;
txtVTag.text = e.itemRenderer.data.VTAG;
txtVState.text = e.itemRenderer.data.VSTATE;
txtVYear.text = e.itemRenderer.data.VYEAR;
txtVCounty.text = e.itemRenderer.data.VCOUNTY;
txtVIns.text = e.itemRenderer.data.VINS;
if (e.itemRenderer.data.VPMT == "A") {
cmbPayment.selectedIndex = 0;
} else if (e.itemRenderer.data.VPMT == "T"){
cmbPayment.selectedIndex = 1;
} else {
cmbPayment.selectedIndex = -1;
}
txtPhone.text = e.itemRenderer.data.PHONE;
if (e.itemRenderer.data.DECALVOIDED == "V") {
chkVoid.selected = true;
lblVoidValue.label = "Void";
} else {
chkVoid.selected = false;
lblVoidValue.label = null;
}
if (e.itemRenderer.data.ADDITIONAL == "A") {
chkAdditional.selected = true;
lblAdditional.label = "Additional";
} else {
chkAdditional.selected = false;
lblAdditional.label = null;
}
}
public function handleResult(event:ResultEvent):void {
/*var urlRequest:URLRequest = new URLRequest('http://webprod.jsu.edu/pd-test/admin/flextest.html');
navigateToURL(urlRequest,"_self");*/
}
public function handleFault(event:FaultEvent):void {
}
private function filterTag():void {
datalist.filterFunction = filterTagMyArrayCollection;
datalist.refresh();
}
private function filterTagMyArrayCollection(item:Object):Boolean {
var searchString:String = searchTag.text.toLowerCase();
var itemName:String = (item.VTAG as String).toLowerCase();
return itemName.indexOf(searchString) > -1;
}
private function filterDL():void {
datalist.filterFunction = filterDLMyArrayCollection;
datalist.refresh();
}
private function filterDLMyArrayCollection(item:Object):Boolean {
var searchString:String = searchDL.text;
var itemName:String = (item.DLNUM as String);
return itemName.indexOf(searchString) > -1;
}
private function filterDecal():void {
datalist.filterFunction = filterDecalMyArrayCollection;
datalist.refresh();
}
private function filterDecalMyArrayCollection(item:Object):Boolean {
var searchString:String = searchDecal.text;
var itemName:String = (item.DECALNUMPERM as String);
return itemName.indexOf(searchString) > -1;
}
/*private function filterID():void {
datalist.filterFunction = filterIDMyArrayCollection;
datalist.refresh();
}
private function filterIDMyArrayCollection(item:Object):Boolean {
var searchString:String = searchID.text.toLowerCase();
var itemName:String = (item.STUDENTPIDM as String).toLowerCase();
return itemName.indexOf(searchString) > -1;
} */
private function filterName():void {
datalist.filterFunction = filterNameMyArrayCollection;
datalist.refresh();
}
private function filterNameMyArrayCollection(item:Object):Boolean {
var searchString:String = searchName.text.toLowerCase();
var itemName:String = (item.STUDENTNAME as String).toLowerCase();
return itemName.indexOf(searchString) > -1;
}
private function clearNameTextInput():void {
if (firstTimeName == true )
{
searchName.text = "";
firstTimeName = false;
}
}
/*
private function clearIDTextInput():void {
if (firstTimeID == true )
{
searchID.text = "";
firstTimeID = false;
}
} */
private function clearDLTextInput():void {
if (firstTimeDL == true )
{
searchDL.text = "";
firstTimeDL = false;
}
}
private function clearTagTextInput():void {
if (firstTimeTag == true )
{
searchTag.text = "";
firstTimeTag = false;
}
}
private function clearDecalTextInput():void {
if (firstTimeDecal == true )
{
searchDecal.text = "";
firstTimeDecal = false;
}
}
protected function button1_clickHandler(event:MouseEvent):void
{
//What happens when we click the refresh button
var urlRequest:URLRequest = new URLRequest('http://webprod.jsu.edu/pd-test/guest/whiteadmin.php');
navigateToURL(urlRequest,"_self");
}
protected function btnSave_clickHandler(event:MouseEvent):void
{
//What happens when we click the save button
form1.send();
}
protected function chkVoid_clickHandler(event:MouseEvent):void
{
//What happens when we click Void Checkbox
if (chkVoid.selected.valueOf() == true) {
lblVoidValue.label = "Void";
} else {
lblVoidValue.label = null;
}
}
protected function chkAdditional_clickHandler(event:MouseEvent):void
{
// What happens when we click Additional Checkbox
if (chkAdditional.selected.valueOf() == true) {
lblAdditional.label = "Additional";
} else {
lblAdditional.label = null;
}
}
protected function button3_clickHandler(event:MouseEvent):void
{
//What happens when we click the register white button
var urlRequest:URLRequest = new URLRequest('http://webprod.jsu.edu/pd-test/registerwhite.php');
navigateToURL(urlRequest,"_self");
}
protected function button4_clickHandler(event:MouseEvent):void
{
// TODO Auto-generated method stub
var urlRequest:URLRequest = new URLRequest('http://webprod.jsu.edu/pd-test/admin/dispatch.php');
navigateToURL(urlRequest,"_self");
}
protected function dg_changeHandler(event:ListEvent):void
{
// TODO Auto-generated method stub
}
]]>
</mx:Script>
<!-- Service Calls -->
<mx:HTTPService url="http://webprod.jsu.edu/pd-test/guestxml.php"
id="xmlFromDatabase"
showBusyCursor="true"
result="resultHandler(event)"
method="POST" >
</mx:HTTPService>
<mx:HTTPService id="form1"
url="http://webprod.jsu.edu/pd-test/guestupdate.php"
method="POST"
result="handleResult(event)"
resultFormat="text" >
<mx:request>
<txtTuid>
{txtTuid.text}
</txtTuid>
<txtStudentName>
{txtStudentName.text}
</txtStudentName>
<txtDecalYear>
{txtDecalYear.text}
</txtDecalYear>
<txtDecalType>
{txtDecalType.text}
</txtDecalType>
<txtConfNo>
{txtConfNo.text}
</txtConfNo>
<txtDecNo>
{txtDecNo.text}
</txtDecNo>
<txtCategory>
{cmbCategory.selectedItem.data}
</txtCategory>
<dateOrigDate>
{txtOriginalDate.text}
</dateOrigDate>
<txtNote>
{txtNote.text}
</txtNote>
<txtDLic>
{txtDLic.text}
</txtDLic>
<txtDLState>
{txtDLState.text}
</txtDLState>
<txtVMake>
{txtVMake.text}
</txtVMake>
<txtVModel>
{txtVModel.text}
</txtVModel>
<txtVBody>
{txtVBody.text}
</txtVBody>
<txtVColor>
{txtVColor.text}
</txtVColor>
<txtVTag>
{txtVTag.text}
</txtVTag>
<txtVState>
{txtVState.text}
</txtVState>
<txtVYear>
{txtVYear.text}
</txtVYear>
<txtVCounty>
{txtVCounty.text}
</txtVCounty>
<txtVIns>
{txtVIns.text}
</txtVIns>
<txtVPmt>
{cmbPayment.selectedItem.data}
</txtVPmt>
<txtPhone>
{txtPhone.text}
</txtPhone>
<lblVoidValue>
{lblVoidValue.label}
</lblVoidValue>
<lblAdditional>
{lblAdditional.label}
</lblAdditional>
</mx:request>
</mx:HTTPService>
<mx:Label x="6" y="4" text="White Decal Dispatch" fontWeight="bold" color="#CC3333" fontSize="30"/>
<mx:DataGrid x="10" y="53" dataProvider="{datalist}" id="dg" itemClick="onItemClick( event );" height="255" width="1009" change="dg_changeHandler(event)">
<mx:columns>
<!--<mx:DataGridColumn width="50" headerText="uid" dataField="TUID"/>-->
<mx:DataGridColumn width="30" headerText="Year" dataField="DECALYEAR"/>
<mx:DataGridColumn width="80" headerText="Name" dataField="STUDENTNAME"/>
<mx:DataGridColumn width="23" headerText="Conf #." dataField="DECALNUMBER"/>
<mx:DataGridColumn width="23" headerText="Decal #" dataField="DECALNUMPERM"/>
<mx:DataGridColumn width="10" headerText="Typ" dataField="DECALTYPE"/>
<mx:DataGridColumn width="20" headerText="Cat" dataField="DECALCAT"/>
<mx:DataGridColumn width="30" headerText="dlnum" dataField="DLNUM"/>
<mx:DataGridColumn width="12" headerText="dlstate" dataField="DLSTATE"/>
<mx:DataGridColumn width="20" headerText="Make" dataField="VMAKE"/>
<mx:DataGridColumn width="30" headerText="Model" dataField="VMODEL"/>
<mx:DataGridColumn width="12" headerText="Body" dataField="VBODY"/>
<mx:DataGridColumn width="15" headerText="Year" dataField="VYEAR"/>
<mx:DataGridColumn width="10" headerText="Color" dataField="VCOLOR"/>
<mx:DataGridColumn width="30" headerText="Tag" dataField="VTAG"/>
<mx:DataGridColumn width="12" headerText="State" dataField="VSTATE"/>
<mx:DataGridColumn width="30" headerText="County" dataField="VCOUNTY"/><!--
<mx:DataGridColumn width="50" headerText="Ins" dataField="VINS"/>
<mx:DataGridColumn width="20" headerText="Pmt" dataField="VPMT"/>-->
<mx:DataGridColumn width="5" headerText="Rec" dataField="DECALPICKEDUP"/>
<!--<mx:DataGridColumn width="20" headerText="decalvoided" dataField="DECALVOIDED"/>
<mx:DataGridColumn width="50" headerText="origdate" dataField="ORIGDATE"/>
<mx:DataGridColumn width="50" headerText="updtdate" dataField="UPDTDATE"/>
<mx:DataGridColumn width="20" headerText="charged" dataField="CHARGED"/>
<mx:DataGridColumn width="50" headerText="chargedate" dataField="CHARGEDATE"/>
<mx:DataGridColumn width="50" headerText="decalnotes" dataField="DECALNOTES"/>-->
</mx:columns>
</mx:DataGrid>
<mx:Form id= "frmUpdateDecal" x="710" y="336" width="309" height="363">
<mx:FormItem label="DLic#">
<mx:TextInput id="txtDLic" maxChars="20"/>
</mx:FormItem>
<mx:FormItem label="DLic State:">
<mx:TextInput id="txtDLState" maxChars="2"/>
</mx:FormItem>
<mx:FormItem label="Vehicle Make:">
<mx:TextInput id="txtVMake" maxChars="4"/>
</mx:FormItem>
<mx:FormItem label="Vehicle Model:">
<mx:TextInput id="txtVModel" maxChars="20"/>
</mx:FormItem>
<mx:FormItem label="Vehicle Body:">
<mx:TextInput id="txtVBody" maxChars="4"/>
</mx:FormItem>
<mx:FormItem label="Vehicle Color:">
<mx:TextInput id="txtVColor" maxChars="3"/>
</mx:FormItem>
<mx:FormItem label="Vehicle Tag:">
<mx:TextInput id="txtVTag" maxChars="20"/>
</mx:FormItem>
<mx:FormItem label="Tag State:">
<mx:TextInput id="txtVState" maxChars="2"/>
</mx:FormItem>
<mx:FormItem label="Vehicle Year:">
<mx:TextInput id="txtVYear" maxChars="4"/>
</mx:FormItem>
<mx:FormItem label="Tag County:">
<mx:TextInput id="txtVCounty" maxChars="20"/>
</mx:FormItem>
<mx:FormItem label="Insurance:">
<mx:TextInput id="txtVIns" maxChars="50"/>
</mx:FormItem>
<mx:FormItem label="Phone:">
<mx:TextInput id="txtPhone" maxChars="11"/>
</mx:FormItem>
</mx:Form>
<mx:Button x="539" y="725" label="Refresh" width="156" click="button1_clickHandler(event)"/>
<mx:Button x="710" y="17" label="Add White Decal" width="117" click="button3_clickHandler(event)"/>
<mx:ApplicationControlBar x="10" y="365" width="261" height="334">
<mx:Form height="268" width="236" y="25">
<mx:FormItem>
<mx:Label text="Name:" color="#CC3333" fontWeight="bold" fontStyle="italic" textDecoration="underline"/>
</mx:FormItem>
<mx:TextInput id="searchName" change="filterName()"
enabled="true"
focusIn="clearNameTextInput()"
text="Filter/Search Name"
width="202" height="26" color="#2B4381"/>
<mx:FormItem>
<mx:Label text="Tag:" color="#CC3333" fontWeight="bold" fontStyle="italic" textDecoration="underline"/>
</mx:FormItem>
<!--
<mx:TextInput id="searchID" change="filterID()"
enabled="true"
focusIn="clearIDTextInput()"
text="Filter/Search JSU ID"
width="204" height="26" color="#2B4381"/> -->
<mx:TextInput id="searchTag" change="filterTag()"
enabled="true"
focusIn="clearTagTextInput()"
text="Filter/Search Tag"
width="201" height="26" color="#2B4381"/>
<mx:FormItem>
<mx:Label text="Driver's License:" color="#CC3333" fontWeight="bold" fontStyle="italic" textDecoration="underline"/>
</mx:FormItem>
<mx:TextInput id="searchDL" change="filterDL()"
enabled="true"
focusIn="clearDLTextInput()"
text="Filter/Search Driver's License"
width="200" height="26" color="#2B4381"/>
<mx:FormItem>
<mx:Label text="Decal Number:" color="#CC3333" fontWeight="bold" fontStyle="italic" textDecoration="underline"/>
</mx:FormItem>
<mx:TextInput id="searchDecal" change="filterDecal()"
enabled="true"
focusIn="clearDecalTextInput()"
text="Filter/Search Decal Number"
width="200" height="26" color="#2B4381"/>
</mx:Form>
</mx:ApplicationControlBar>
<mx:FormItem label="Confirmation No:" x="299" y="403" width="219" fontStyle="italic">
<mx:TextInput id="txtConfNo" width="119" editable="false" contentBackgroundAlpha="1.0" dropShadowVisible="false" borderVisible="false" color="#CC3333" maxChars="5"/>
</mx:FormItem>
<mx:FormItem label="System Tranaction ID:" x="276" y="426" width="240" fontStyle="italic">
<mx:TextInput id="txtTuid" width="118" editable="false" borderVisible="false" color="#CC3333"/>
</mx:FormItem>
<mx:Label x="16" y="325" text="Search" fontWeight="bold" color="#CC3333" fontSize="22"/>
<mx:FormItem label="Justification/Notes:" x="294" y="586">
<mx:TextArea id="txtNote" width="292" height="85"/>
</mx:FormItem>
<mx:FormItem label="Decal#:" x="571" y="477" width="121">
<mx:TextInput id="txtDecNo" width="65" maxChars="5"/>
</mx:FormItem>
<mx:FormItem label="Category" x="489" y="507">
<mx:ComboBox id="cmbCategory"
prompt="Select Decal Category"
selectedIndex="-1">
<mx:dataProvider>
<mx:Object label="White" data="WHIT" />
</mx:dataProvider>
</mx:ComboBox>
</mx:FormItem>
<mx:FormItem label="Payment Type" x="445" y="535">
<mx:ComboBox id="cmbPayment"
prompt="Select Payment Type"
selectedIndex="-1" width="160">
<mx:dataProvider>
<mx:Object label="Payment Upon Request" data="A" />
<mx:Object label="Tag or 25yrs service FREE" data="T" />
</mx:dataProvider>
</mx:ComboBox>
</mx:FormItem>
<mx:FormItem id="lblAdditional" color="#2FAB5E" x="525" y="561">
<mx:CheckBox label="$1.00 Additional" fontStyle="italic" color="#2F3F81" id="chkAdditional" click="chkAdditional_clickHandler(event)"/>
</mx:FormItem>
<mx:FormItem label="" id="lblVoidValue" color="#D21703" fontSize="13" fontFamily="Verdana" fontWeight="bold" fontStyle="normal" x="410" y="687">
<mx:CheckBox label="Void" id="chkVoid" click="chkVoid_clickHandler(event)" color="#2F3F81" fontSize="10" fontFamily="Arial" fontStyle="italic"/>
</mx:FormItem>
<mx:FormItem label="Order Date:" x="509" y="415" width="62">
</mx:FormItem>
<mx:FormItem label="Pick-up Date:" x="501" y="448" width="72">
</mx:FormItem>
<mx:FormItem label="Dec Year:" x="310" y="448" fontStyle="italic">
<mx:TextInput id="txtDecalYear" width="79" borderVisible="false" color="#CC3333"/>
</mx:FormItem>
<mx:FormItem label="Guest Name" x="460" y="371">
<mx:TextInput id="txtStudentName" width="152" maxChars="100"/>
</mx:FormItem>
<mx:Button label="Save" width="156" id="btnSave" click="btnSave_clickHandler(event)" x="539" y="685"/>
<mx:FormItem label="Decal Type:" x="458" y="477" width="103">
<mx:TextInput id="txtDecalType" width="26"/>
</mx:FormItem>
<mx:Label x="297" y="324" text="Decal Info" fontWeight="bold" color="#CC3333" fontSize="22"/>
<mx:TextInput x="571" y="413" width="119" id="txtOriginalDate" maxChars="50"/>
<mx:TextInput x="571" y="446" width="119" id="txtUpdateDate" maxChars="50"/>
<mx:Button x="850" y="17" label="Return to Decal Dispatch" width="173" click="button4_clickHandler(event)"/>
</mx:Application>
答案 0 :(得分：3)
更改此行：
var itemName:String = (item.DECALNUMPERM as String);
到
return item.DECALNUMPERM＆amp;＆amp; item.DECALNUMPERM.toString（）。indexOf（searchString）＆gt; -1;
item.DECALNUMPERM是一个数字，将其转换为String将导致为空。
你有没有理由使用Flex 3而不是Flex 4？
修改此外，有时item.DECALNUMPERM为空。因此，您需要检查null以及执行toString（）。请尝试使用此行：
return item.DECALNUMPERM && item.DECALNUMPERM.toString().indexOf(searchString) > -1;
您还需要在其他地方进行更改，例如：
private function filterTagMyArrayCollection(item:Object):Boolean {
var searchString:String = searchTag.text.toLowerCase();
var itemName:String = (item.VTAG as String).toLowerCase();
return itemName.indexOf(searchString) > -1;
}
和
private function filterDLMyArrayCollection(item:Object):Boolean {
var searchString:String = searchDL.text;
var itemName:String = (item.DLNUM as String);
return itemName.indexOf(searchString) > -1;
}
答案 1 :(得分：1)
正如错误所说，导致问题的功能是：
private function filterDecalMyArrayCollection(item:Object):Boolean {
var searchString:String = searchDecal.text;
var itemName:String = (item.DECALNUMPERM as String);
return itemName.indexOf(searchString) > -1;
}
当DECALNUMPERM属性为null时，可能会失败，因为提到的错误。你有没有试过调试这个？