Apex will allow you to make an order List of objects that you can then iterate over and manipulate. However, Apex will not let you use the built-in sort method for List to sort sObjects by a field inside. To do this, we have to implement our own comparable class to do the sorting for us.
To implement the Comparable interface, you must first declare a class with the implements keyword as follows
global class Employee implements Comparable {}
Next, your class must provide an implementation for the following method:
global Integer compareTo(Object compareTo) {}
Note: The implemented method must be declared as global or public.
The implementation of this method should return the following values:
-
The current value is greater than the compared value: return 1 -
The current value is equal to the compared value: return 0 -
The current value is less than the compared value: return -1
If we want to develop different type of sorting like column sorting, multilevel sorting on collection to show the collection on visualforce page.
e.g.
Visualforce page:
<apex:page controller="compare1_sorting">
<apex:form >
<style type="text/css">
th{text-align:center;}
.button {
}
.customPopup {
background-color: white;
border-style: solid;
border-width: 1px;
padding: 25px;
padding-bottom:35px;
width: 500px;
margin-left: 200px;
margin-top: -100px;
position:fixed;
top:49%;
}
.disabledTextBox {
background-color: white;
border: 1px solid;
color: black;
cursor: default;
width: 90px;
display: table;
padding: 5px 1px;
text-align:right;
}
tr .totalRow:first-child{
text-align:left !important;
}
.totalRow
{
text-align:right;
}
.closeButton {
float: right;
}
</style>
<apex:commandButton value="Multi Field Sort" action="{!MultiFieldSort}" rerender="popup" status="status"/>
<apex:outputPanel id="popup">
<apex:outputPanel id="popInnerOutputPnl" styleClass="customPopup" layout="block" rendered="{!displayPopUp}">
<apex:pageBlock >
<apex:pageBlockButtons location="top" >
<apex:commandButton style=" align:right; margin-top: -28px; margin-right: -30px;border: none;" value="X" title="Close the popup" action="{!closePopup}" styleClass="closeButton" rerender="popup"/>
<a class="btn" style="text-decoration: none; margin-left: -146px; padding: 5px 5px 5px 5px;" onclick="AddNewRow();">Add Level</a>
<!--<apex:commandbutton style="margin-left: -149px;" value="Add Level" action="{!addrow}" immediate="true" rerender="ref"/>-->
</apex:pageBlockButtons>
<apex:pageblocktable value="{!sortwrapperList}" var="swp" id="ref">
<apex:variable value="{!0}" var="cnt"/>
<apex:column >
{!swp.sortby}
</apex:column>
<apex:column headerValue="Column">
<apex:selectList id="sortselect" multiselect="false" size="1" value="{!swp.sortselect}" style="margin-left:46px;">
<apex:selectOptions value="{!sortList}" />
</apex:selectList>
</apex:column>
<apex:column headerValue="order">
<apex:selectList id="orderselect" multiselect="false" size="1" value="{!swp.orderselect}" style="margin-left:25px;">
<apex:selectOptions value="{!orderList}" />
</apex:selectList>
</apex:column>
<apex:column headervalue="Action">
<a style="cursor: pointer; text-decoration: none;" onclick="removerow('{!cnt}');">Remove</a>
<apex:variable var="cnt" value="{!cnt+1}"/>
</apex:column>
</apex:pageblocktable>
</apex:pageBlock>
<apex:commandbutton style="position: absolute; right: 50%;width: 50px; height: 27px;" value="OK" action="{!ok}"/>
</apex:outputPanel>
</apex:outputPanel>
<apex:outputPanel id="panelId">
<apex:pageBlock >
<apex:pageblockTable value="{!wrapperList}" var="wrapRec" >
<!-- <apex:column styleClass="actionColumn" headerValue="Action">
<a href="/{!wrapRec.myId.Id}/e?retURL={!wrapRec.myId.Id}" target="_parent" class="actionLink">Edit</a>
|
<a href="/{!wrapRec.myId.Id}" target="_parent" class="actionLink">View</a>
<apex:facet name="footer">
Sub Total
</apex:facet>
</apex:column>-->
<apex:column style="text-align:center;width:92px;" value="{!wrapRec.Count}">
<apex:facet name="header">
<a style="cursor: pointer;" onclick="sortcolumn('1','{!IF(Order=='asc', 'desc', 'asc')}');" >
Number {!IF(fieldname=='1',IF(Order=='desc','↡','↟'),'')}</a>
</apex:facet>
</apex:column>
<apex:column style="text-align:center; width:99px;" value="{!wrapRec.Name}">
<apex:facet name="header">
<a style="cursor: pointer;" onclick="sortcolumn('2','{!IF(Order=='asc', 'desc', 'asc')}');" >
Name {!IF(fieldname=='2',IF(Order=='desc','↡','↟'),'')}</a>
</apex:facet>
</apex:column>
<apex:column style="text-align:center; width: 98px;" value="{!wrapRec.email}">
<apex:facet name="header">
<a style="cursor: pointer;" onclick="sortcolumn('3','{!IF(Order=='asc', 'desc', 'asc')}');" >
email {!IF(fieldname=='3',IF(Order=='desc','↡','↟'),'')}</a>
</apex:facet>
</apex:column>
<apex:column style="text-align:center; width: 98px;" value="{!wrapRec.industry}">
<apex:facet name="header">
<a style="cursor: pointer;" onclick="sortcolumn('4','{!IF(Order=='asc', 'desc', 'asc')}');" >
phone {!IF(fieldname=='3',IF(Order=='desc','↡','↟'),'')}</a>
</apex:facet>
</apex:column>
</apex:pageblockTable>
</apex:pageBlock>
</apex:outputPanel>
<apex:actionFunction name="addrow" action="{!addrow}" reRender="ref"/>
<apex:actionFunction name="removelevel" action="{!removelevel}" rerender="ref">
<apex:param name="obj" value="" assignTo="{!index}"/>
</apex:actionFunction>
<apex:actionFunction name="sortheader" action="{!sortheader}" rerender="panelId">
<apex:param name="obj1" value="" assignTo="{!fieldname}"/>
<apex:param name="obj2" value="" assignTo="{!order}"/>
</apex:actionFunction>
</apex:form>
<script>
function jump(){
$("body, html").animate({
scrollTop: ($('.jumper123').first().offset().top)
}, 1000);
}
function paginationnum(){
setPagecount();
}
function AddNewRow(){
addrow();
}
function removerow(obj) {
removelevel(obj);
}
function sortcolumn(obj1, obj2) {
sortheader(obj1, obj2);
}
</script>
</apex:page>
Controller:
public class compare1_sorting {
public Id Accid;
public string index{get; set;}
public string fieldname{get; set;}
public string order{get; set;}
public string AccountName{get; set;}
public string Affiliationfilter{get; set;}
public string GAUfilter{get; set;}
public string CampaignNamefilter{get; set;}
public string filter{get; set;}
public List<myWrapperClass> wrapperList {get; set;}
public List<sortWrapperClass> sortwrapperList {get; set;}
public static Map<string, string> sortMap= new Map<string, string>();
public Boolean displayPopup {get;set;}
public decimal pagetotalAmount{get;set;}
public decimal pagetotalPipelineAmount{get;set;}
public decimal totalAmount{get;set;}
public decimal totalPipelineAmount{get;set;}
public integer Recordcount{get;set;}
public integer sortcount=1;
public string paginationselect{get; set;}
//public List<myWrapperClass> pagewrapperList {get; set;}
Map<integer,List<myWrapperClass>> mapOpportunityPages = new Map<integer,List<myWrapperClass>>();
public integer intPageNumber{get;set;}
public integer intNumberofPages{get;set;}
List<Account> acclst;
public compare1_sorting(){
order='asc';
wrapperList= new List<MyWrapperClass>();
acclst= [Select name , Email__c, Industry from account limit 10];
system.debug('acc==========='+acclst);
integer i=0;
for(Account acc: acclst){
i++;
wrapperList.add(new myWrapperClass(i, acc.name, acc.email__c, acc.Industry));
}
wrapperList.sort();
system.debug('wrapperList==========='+wrapperList);
}
public void Applyfilter(){
//wrapperList.add(new myWrapperClass(id1, Aff1, gdate1, gtype1, amount1, TotalSplitamount1, PipelineAmount1, camp1, GAU1, createddated1 ));
// wrapperList.sort();
}
public void MultiFieldSort(){
sortcount=1;
displayPopup = true;
sortwrapperList= new List<sortWrapperClass>();
sortwrapperList.add(new sortWrapperClass('Sort by','',''));
}
public void sortheader(){
sortwrapperList= new List<sortWrapperClass>();
system.debug('fieldname==='+fieldname+'order========='+order);
sortwrapperList.add(new sortWrapperClass('Single', fieldname, order));
for(sortWrapperClass swp:sortwrapperList){
sortMap.put(swp.sortselect, swp.orderselect);
}
wrapperList.sort();
}
public void closePopup() {
displayPopup = false;
}
public void addrow(){
sortcount=sortcount+1;
if(sortcount<9)
sortwrapperList.add(new sortWrapperClass('Then by','',''));
}
Public List<SelectOption> getsortList(){
List<SelectOption> sortOptions = new List<SelectOption>();
sortOptions.add(new SelectOption('1','Number'));
sortOptions.add(new SelectOption('2','Name'));
sortOptions.add(new SelectOption('3','email'));
sortOptions.add(new SelectOption('4','Phone'));
return sortOptions;
}
Public List<SelectOption> getorderList(){
List<SelectOption> filterOptions = new List<SelectOption>();
filterOptions.add(new SelectOption('asc', 'ASC'));
filterOptions.add(new SelectOption('desc', 'DESC'));
return filterOptions;
}
public void removelevel(){
sortcount=sortcount-1;
Integer indexVal = Integer.valueof(index);
if(sortwrapperList[indexval -1]!= null && indexVal>1)
sortwrapperList.remove(indexval-1);
}
public void ok(){
fieldname='';
displayPopup = false;
system.debug('sortwrapperList========='+sortwrapperList);
for(sortWrapperClass swp:sortwrapperList){
sortMap.put(swp.sortselect, swp.orderselect);
}
wrapperList.sort();
}
public class sortWrapperClass{
public string sortselect{get; set;}
public string orderselect{get; set;}
public string sortby{get; set;}
public sortWrapperClass(string by1, string sortselect1, string orderselect1){
this.sortby=by1;
if(by1=='Single'){
this.sortselect=sortselect1;
this.orderselect=orderselect1;
}
else{ this.sortselect=sortselect;
this.orderselect=orderselect;
}
}
}
public class myWrapperClass implements Comparable{
public integer count{get; set;}
public string name{get; set;}
public string email{get; set;}
public string industry{get; set;}
public myWrapperClass(integer num, string nam, string emailid, string indus){
this.count=num;
this.name=nam;
this.email=emailid;
this.industry=indus;
}
public Integer compareTo(Object compareTo) {
myWrapperClass compareToEventTask = (myWrapperClass)compareTo;
if(sortMap.size()==0){
if (count== compareToEventTask.count)
return 0;
if (count> compareToEventTask.count)
return 1;
else
return -1;
}
else if(sortMap.size()>0){
for(string srt:sortMap.keySet()){
if(srt=='1'){
if (count<compareToEventTask.count)
return sortMap.get('1')=='asc'?-1:1;
if (count> compareToEventTask.count)
return sortMap.get('1')=='asc'?1:-1;
}
if(srt=='2'){
if (name<compareToEventTask.name)
return sortMap.get('2')=='asc'?-1:1;
if (name> compareToEventTask.name)
return sortMap.get('2')=='asc'?1:-1;
}
if(srt=='3'){
if (email<compareToEventTask.email)
return sortMap.get('3')=='asc'?-1:1;
if (email> compareToEventTask.email)
return sortMap.get('3')=='asc'?1:-1;
}
if(srt=='4'){
if (industry<compareToEventTask.industry)
return sortMap.get('4')=='asc'?-1:1;
if (industry> compareToEventTask.industry)
return sortMap.get('4')=='asc'?1:-1;
}
}
}
return 0;
}
}
}