Before creating a custom button or link, determine what action you want to occur when a user clicks it. Consider a Visualforce page if you want the button or link to launch a custom page or other code(salesforce help).
We can execute Javascript or Apex Class within a visualforce page action.But we will not talk about the Onclick today,you can achieve your business by webservice or remote object.
Today we will implement a custom button through a visualforce page, in the page ,init a Action and accomplish the logic in the apex controller
The scenario is described below:
1,When our business unit launched a campaign,the user will apply marketing budget.Certainly,we will manage the approve flow by salesforce standard approve process.
2,We Create a custom object: event request,and it has a field named status and contains these picklist value (Submitted, Approved, Reject, Cancelled );
3,The status field is read only to the user,and update by approve process
4,But there is a question,when the user want to cancel the request,he can not change the status field directly
5,So,we need a Cancel Button to do it.
Here is the flows:
1,Create a visualforce page,very simple :
<apex:page standardController="Event_Request__c"
extensions="ctrlExt_EventRequestCancel"
action="{!customCancel}">
<apex:Pagemessages id="msgs"/>
<apex:sectionHeader title="Auto-Running Apex Code"/>
<apex:outputPanel >
If you see this page, it must be something wrong.Please contact the administraor.
</apex:outputPanel>
</apex:page>
2,Create a extension controller
public with sharing class ctrlExt_EventRequestCancel {
private final ApexPages.StandardController stdController;
public Event_Request__c eq{get;set;}
public ctrlExt_EventRequestCancel(ApexPages.StandardController stdController)
{
this.stdController = stdController;
list fieldsList = new list ();
fieldsList.add('Status__c');
if(!Test.isRunningTest())
{
stdcontroller.addFields(fieldsList);
}
this.eq = (Event_Request__c)stdcontroller.getRecord();
system.debug('this.eq1: ' + this.eq );
}
public PageReference customCancel()
{
try
{
if(null != this.eq && 'Cancelled' != this.eq.Status__c)
{
this.eq.Status_MDT_AP__c='Cancelled';
update this.eq;
return this.stdController.view().setRedirect(true);
}
}catch(exception e)
{
ApexPages.Message Msg = new ApexPages.Message(ApexPages.Severity.Info,e.getMessage());
ApexPages.addMessage(Msg);
}
return null;
}
}
3,In the Object describe page,create a new button:
4,Congratulations,you have got a new Custom Button.