Hi,

Try the below code snippet as reference:

<apex:page controller="DescribeSobjectTest" showHeader="false" sidebar="false" id="pageid">
<script>
body .bPageBlock {
border-top-width: 0px;
margin-bottom: 10px;
padding: 0;
}
</script>
<script src="/soap/ajax/16.0/connection.js" type="text/javascript"></script>
<script src="/soap/ajax/16.0/apex.js" type="text/javascript"></script>
<script type="text/javascript" src="/js/functions.js"></script>
<apex:form id="formid">
<apex:outputPanel id="panel1">
<script>
var SelectConId1='';

function transfervalue(na)
{

if(na=='pageid:formid:j_id3:j_id4:j_id5'||na==null)
{
alert('Please select a value');
}
else
{
var setname = "{!$CurrentPage.parameters.nameid}";

window.parent.opener.document.getElementById("{!$CurrentPage.parameters.nameid}").value = na;
window.parent.close();

}
return false;
}
function checkone(cb)
{
var countchbox=0;
if(cb.checked)
{

if((SelectConId1.length)<=1)
{
SelectConId1=cb.name;
}
else
{
SelectConId1=SelectConId1+','+cb.name;
}
}
else if((cb.checked)!=true)
{
if((SelectConId1.length)==1)
{
alert('Hello'+cb.checked);
SelectConId1=cb.name;
}
else
{
var allids=SelectConId1.split(',');
var idarray='';
for(var i=0;i<allids.length;i++)
{
if(allids[i]!=cb.name && allids[i]!='')
{
idarray=idarray+','+allids[i];
}
}

}
}

return SelectConId1;
}
function deselectAll()
{
SelectConId1='';
return false;
}
</script>

<apex:image url="{!URLFOR($Resource.lookupwindowHeader, 'image/lookupwindowhr.gif')}" />
<apex:pageBlock >

<apex:pageBlockButtons location="both" >
<apex:commandButton value="Insert Selected" onclick="return transfervalue(checkone(this));"/>
</apex:pageBlockButtons>
<apex:outputLink onclick="deselectAll();" >Deselect All</apex:outputLink>
<apex:pageBlockTable value="{!lookupvalue}" var="cc" id="pbtable">
<apex:column style="width:3%;">
<apex:facet name="header">
</apex:facet>
<input type="checkbox" name="{!cc}" onclick= "checkone(this) " id="checkedone" />
</apex:column>
<div id="{!cc}">
<apex:column >
<apex:facet name="header" >{!$CurrentPage.parameters.Sobject}&nbsp;Name</apex:facet>
{!cc}
</apex:column>
</div>
</apex:pageBlockTable>

</apex:pageBlock>

<!--/div-->
<div class="pbFooter secondaryPalette">
<div class="bg"></div>
</div>


<!--<center> <apex:commandButton value="Insert Selected" id="theButton" onclick="return transfervalue(checkone(this));"/></center>-->


<div id="norecord" style="display:none;">
No Record Found
</div>
</apex:outputPanel>
</apex:form>
</apex:page>

public class DescribeSobjectTest
{
public list<string> lookupvalue{get;set;}
public list<sObject> datalist{get;set;}
Map<String, Schema.SObjectField> M;
public List<SObjectField> ObjField{get;set;}
public List<SelectOption> fieldsvalues{get;set;}

public DescribeSobjectTest()
{
lookupvalue = new list<string>();

M = new Map<String, Schema.SObjectField>();
ObjField = new List<SObjectField>();
fieldsvalues = new List<SelectOption>();

string queryObjectstr = ((ApexPages.currentPage().getParameters().get('Sobject') == null || ApexPages.currentPage().getParameters().get('Sobject') == '')?null:ApexPages.currentPage().getParameters().get('Sobject'));

if(queryObjectstr == 'Contact')
{
M = Schema.SObjectType.Contact.fields.getMap();
}
if(queryObjectstr == 'Account')
{
M = Schema.SObjectType.Account.fields.getMap();
}
if(queryObjectstr == 'Contact')
{
M = Schema.SObjectType.Contact.fields.getMap();
}
Schema.SObjectField f21 = M.get('Name');

ObjField = M.values();
for(integer j = 0 ; j < ObjField.size() ; j++)
{
String str = String.Valueof(ObjField[j]);
fieldsvalues.add(new SelectOption(str,str));
}

string picklistvalue2 = ((ApexPages.currentPage().getParameters().get('pickval') == null || ApexPages.currentPage().getParameters().get('pickval') == '' || ApexPages.currentPage().getParameters().get('pickval') == 'undefine')?null:ApexPages.currentPage().getParameters().get('pickval'));
if(picklistvalue2 != null)
{
Schema.SObjectField f = M.get(picklistvalue2);
system.debug('*******' + f.getDescribe().getType());
if(String.Valueof(f.getDescribe().getType()) == 'BOOLEAN' || String.Valueof(f.getDescribe().getType()) == 'PICKLIST' || String.Valueof(f.getDescribe().getType()) == 'REFERENCE' || String.Valueof(f.getDescribe().getType()) == 'MULTIPICKLIST')
{

if (String.Valueof(f.getDescribe().getType()) == 'PICKLIST')
{
lookupvalue = new List<String>();
List<Schema.PicklistEntry> ple = f.getDescribe().getPicklistValues();
for(Schema.PicklistEntry p : ple)
lookupvalue.add(p.value);
}
if (String.Valueof(f.getDescribe().getType()) == 'MULTIPICKLIST')
{
lookupvalue = new List<String>();
List<Schema.PicklistEntry> ple = f.getDescribe().getPicklistValues();
for(Schema.PicklistEntry p : ple)
lookupvalue.add(p.getValue());
}
else if(String.Valueof(f.getDescribe().getType()) == 'BOOLEAN')
{
lookupvalue = new List<String>();
lookupvalue.add('True');
lookupvalue.add('False');
}
else if(String.Valueof(f.getDescribe().getType()) == 'REFERENCE')
{
lookupvalue = new List<String>();
list<Schema.SObjectType> queryObject = f.getDescribe().getReferenceTo();
list<sObject> datalist = new list<sObject>();
if(picklistvalue2 != 'RecordTypeId')
datalist = Database.query('select id,name from '+queryObject[0]+' limit 1000');
else
datalist = Database.query('select id,name from RecordType where SobjectType=\''+queryObjectstr+'\' limit 1000');

if(datalist.size()>0)
{
for (sObject d : datalist)
{
lookupvalue.add((String)d.get('Name'));
}
}
}
else
{
}
}
}
}
public void addThis()
{
}

}

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