Hi,

This is possible. Try the following example,

VF page:

<apex:page controller="EgPOPupCon">
   <!-- Popup styling starts here -->    
    ..........................
   <!-- Popup to show while an opportunity is created ENDING-->
    <apex:pageblock >    
        <apex:pageblockSection rendered="{!INPUT == true}">
            <apex:inputtext value="{!name1}"/>         
            <apex:commandbutton value="Save" action="{!showpop}" />
        </apex:pageblockSection>       
        <apex:pageblockSection rendered="{!INPUT == false}">
            <apex:outputtext value="{!name1}"/>           
        </apex:pageblockSection>
    </apex:pageblock>   
  </apex:form>
</apex:page>

Apex Class:

public class EgPOPupCon{
    public Opportunity opp{get;set;}
    public boolean INPUT{get;set;}
    public boolean pop{get;set;}
    public string name1{get;set;}

    public EgPOPupCon(){       
           INPUT = true;
    }    
    public pageReference save(){     
       pop = false;
       input = false;
       opp = new Opportunity(name = name1, stagename = 'Prospecting', closedate = Date.today());
       insert opp;      
       PageReference nextpage1 = new PageReference('/apex/EgPOPup');
       return nextpage1.setRedirect(true);                
    }
    public void showpop(){        
       pop = true;
    }    
    public void reject(){        
       pop = false;
    } 
}

You can modify the page and controller as you would like to do as per your requirement.

Hope so this helps you...!

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