Hide and Show Output Panel

code sample for this

01 / <apex:page standardController="case" extensions="QueryStringController" standardStylesheets="false"showHeader="false" >
02
03 / <apex:form>
04 / <apex:outputPanel id="one" title="one" rendered="{!firstPanel}">
05 / <apex:commandButton value="firstButton" action="{!firstButton}"/>
06 / </apex:outputPanel>
07
08 / <apex:outputPanel id="two" title="two" rendered="{!secondPanel}">
09 / <apex:commandButton value="SecondButton" action="{!secondButton}"/>
10 / </apex:outputPanel>
11
12 / </apex:form>
13
14 / ======Controller code======
15 / global with sharing class QueryStringController {
16
17 / public boolean firstPanel{get;set;}
18 / public boolean secondPanel{get;set;}
19
20 / public QueryStringController(ApexPages.StandardController controller) {
21
22 / firstPanel = true;
23 / secondPanel = true;
24
25 / }
26
27
28 / public void firstButton()
29 / {
30 / firstPanel=false;
31 / secondPanel= true;
32
33 / }
34 / public void secondButton()
35 / {
36 / firstPanel=true;
37 / secondPanel=false;
38 / }
39
40
41 / }

I hope your problem will be solved now