在salesforce VF Page里面实现 Lookup 字段

MyCustomLookup.page

<apex:page controller="MyCustomLookupController" id="Page" tabstyle="Contact">

<script type="text/javascript">
function openLookup(baseURL, width, modified, searchParam){
var originalbaseURL = baseURL;
var originalwidth = width;
var originalmodified = modified;
var originalsearchParam = searchParam;

var lookupType = baseURL.substr(baseURL.length-3, 3);
if (modified == '1') baseURL = baseURL + searchParam;

var isCustomLookup = false;

// Following "001" is the lookup type for Account object so change this as per your standard or custom object
if(lookupType == "001"){

var urlArr = baseURL.split("&");
var txtId = '';
if(urlArr.length > 2) {
urlArr = urlArr[1].split('=');
txtId = urlArr[1];
}

// Following is the url of Custom Lookup page. You need to change that accordingly
baseURL = "/apex/CustomAccountLookup?txt=" + txtId;

// Following is the id of apex:form control "myForm". You need to change that accordingly
baseURL = baseURL + "&frm=" + escapeUTF("{!$Component.myForm}");
if (modified == '1') {
baseURL = baseURL + "&lksearch=" + searchParam;
}

// Following is the ID of inputField that is the lookup to be customized as custom lookup
if(txtId.indexOf('Account') > -1 ){
isCustomLookup = true;
}
}

if(isCustomLookup == true){
openPopup(baseURL, "lookup", 350, 480, "width="+width+",height=480,toolbar=no,status=no,directories=no,menubar=no,resizable=yes,scrollable=no", true);
}
else {
if (modified == '1') originalbaseURL = originalbaseURL + originalsearchParam;
openPopup(originalbaseURL, "lookup", 350, 480, "width="+originalwidth+",height=480,toolbar=no,status=no,directories=no,menubar=no,resizable=yes,scrollable=no", true);
}
}
</script>

<apex:sectionHeader title="Demo"  subtitle="Custom Lookup" />

<apex:form id="myForm">
<apex:PageBlock id="PageBlock">
<apex:pageBlockSection columns="1" title="Custom Lookup">
<apex:inputField id="Account" value="{!contact.AccountId}"  />
</apex:pageBlockSection>
</apex:PageBlock>
</apex:form>

</apex:page>

MyCustomLookupController.cls

public with sharing class MyCustomLookupController {

public Contact contact {get;set;}

public MyCustomLookupController() {
contact = new Contact();
}

}

CustomAccountLookup.page

<apex:page controller="CustomAccountLookupController"
title="Search"
showHeader="false"
sideBar="false"
tabStyle="Account"
id="pg">

<apex:form >
<apex:outputPanel id="page" layout="block" style="margin:5px;padding:10px;padding-top:2px;">
<apex:tabPanel switchType="client" selectedTab="name1" id="tabbedPanel">

<!-- SEARCH TAB -->
<apex:tab label="Search" name="tab1" id="tabOne">

<apex:actionRegion >
<apex:outputPanel id="top" layout="block" style="margin:5px;padding:10px;padding-top:2px;">
<apex:outputLabel value="Search" style="font-weight:Bold;padding-right:10px;" for="txtSearch"/>
<apex:inputText id="txtSearch" value="{!searchString}" />
<span style="padding-left:5px"><apex:commandButton id="btnGo" value="Go" action="{!Search}" rerender="searchResults"></apex:commandButton></span>
</apex:outputPanel>

<apex:outputPanel id="pnlSearchResults" style="margin:10px;height:350px;overflow-Y:auto;" layout="block">
<apex:pageBlock id="searchResults">
<apex:pageBlockTable value="{!results}" var="a" id="tblResults">
<apex:column >
<apex:facet name="header">
<apex:outputPanel >Name</apex:outputPanel>
</apex:facet>
<apex:outputLink value="javascript:top.window.opener.lookupPick2('{!FormTag}','{!TextBox}_lkid','{!TextBox}','{!a.Id}','{!a.Name}', false)" rendered="{!NOT(ISNULL(a.Id))}">{!a.Name}</apex:outputLink>
</apex:column>
</apex:pageBlockTable>
</apex:pageBlock>
</apex:outputPanel>
</apex:actionRegion>

</apex:tab>
<!--
<apex:tab label="New Account" name="tab2" id="tabTwo">

<apex:pageBlock id="newAccount" title="New Account" >

<apex:pageBlockButtons >
<apex:commandButton action="{!saveAccount}" value="Save"/>
</apex:pageBlockButtons>
<apex:pageMessages />

<apex:pageBlockSection columns="2">
<apex:repeat value="{!$ObjectType.Account.FieldSets.CustomAccountLookup}" var="f">
<apex:inputField value="{!Account[f]}"/>
</apex:repeat>
</apex:pageBlockSection>
</apex:pageBlock>

</apex:tab>
-->
</apex:tabPanel>
</apex:outputPanel>
</apex:form>
</apex:page>

CustomAccountLookupController.cls

public with sharing class CustomAccountLookupController {

public Account account {get;set;} // new account to create
public List<Account> results{get;set;} // search results
public string searchString{get;set;} // search keyword

public CustomAccountLookupController() {
account = new Account();
// get the current search string
searchString = System.currentPageReference().getParameters().get('lksrch');
runSearch();
}

// performs the keyword search
public PageReference search() {
runSearch();
return null;
}

// prepare the query and issue the search command
private void runSearch() {
// TODO prepare query string for complex serarches & prevent injections
results = performSearch(searchString);
}

// run the search and return the records found.
private List<Account> performSearch(string searchString) {

String soql = 'select id, name from account';
if(searchString != '' && searchString != null)
soql = soql +  ' where name LIKE \'%' + searchString +'%\'';
soql = soql + ' limit 25';
System.debug(soql);
return database.query(soql);

}

// save the new account record
public PageReference saveAccount() {
insert account;
// reset the account
account = new Account();
return null;
}

// used by the visualforce page to send the link to the right dom element
public string getFormTag() {
return System.currentPageReference().getParameters().get('frm');
}

// used by the visualforce page to send the link to the right dom element for the text box
public string getTextBox() {
return System.currentPageReference().getParameters().get('txt');
}

}