Update custom field on Opportunity on attached file deletion - Lightning

Question

I have setup a trigger to update a custom checkbox Attachment__c on opportunity on uploading or deletion of file as an attachment. This seems to work fine on the file upload but fails every time on deletion of the attached file. Please let me know if I am making any mistake. Thanks in advance for help!

Please find the code below:

trigger OppAttachmentTrigger2 on ContentDocument (after insert,after update) {
if(Trigger.isAfter && Trigger.isInsert ||Trigger.isAfter && Trigger.isUpdate){
    Set<Id> IdCollect = new Set<Id>();
    for(ContentDocument att:Trigger.New){
        if(att.ParentId!=null){
            IdCollect.add(att.ParentId);
        }
    }
    List<Opportunity> oppList = new List<Opportunity>();
    for(Opportunity oppy : [SELECT Id,Attachment__c FROM Opportunity where id=:IdCollect]){
        for(ContentDocument at:Trigger.New){
            if(at.ParentId!=null){
                oppy.Attachment__c = true;
                oppList.add(oppy);
            }    
        }   
    }
    update oppList; 
}

// After delete attachment///

if(Trigger.isBefore && Trigger.isDelete){
Set<Id> IdCollect = new Set<Id>();
for(ContentDocument att:Trigger.Old){
    system.debug('--att '+att);
    if(att.id!=null){
        IdCollect.add(att.Id);
    }
}
List<ContentDocumentLink> cdl = new List<ContentDocumentLink>();
cdl = [SELECT Id,LinkedEntityId FROM ContentDocumentLink WHERE ContentDocumentId IN :IdCollect ];

system.debug('ContentDocumentLink ---- cdl '+cdl);
List<Opportunity> oppList = new List<Opportunity>();
for(Opportunity oppy : [SELECT Id,Attachment__c FROM Opportunity where id=:IdCollect]){   
    oppList.add(oppy);
   oppy.Attachment__c = false;
               }
               
update oppList;

} }

Answer 1

When file is deleted, we are getting null parent id from your code. You will have to query contentdocumentlink from contentDocument and then get parent record id from there. Below is code I tried for before delete, in debug logs I am getting record id I linkedEntityId field. You can use it to update your field on record.

   if(Trigger.isBefore && Trigger.isDelete){
    Set<Id> IdCollect = new Set<Id>();
    for(ContentDocument att:Trigger.Old){
        system.debug('--att '+att);
        if(att.id!=null){
            IdCollect.add(att.Id);
        }
    }
    List<ContentDocumentLink> cdl = new List<ContentDocumentLink>();
    cdl = [SELECT Id,LinkedEntityId FROM ContentDocumentLink WHERE ContentDocumentId IN :IdCollect ];

    system.debug('ContentDocumentLink ---- cdl '+cdl);
    List<Opportunity> oppList1 = new List<Opportunity>();
    for(Opportunity oppy : [SELECT Id FROM Opportunity where id=:IdCollect]){   
        oppList1.add(oppy);
    }     
    system.debug('oppList1 '+oppList1);
    update oppList1;
}

Hope this answers your question.

Answer 2

Hi Muzammil thank you for your help. However when i am using the code for my requirement it is still not working. Please let me know where am I going wrong.

 if(Trigger.isBefore && Trigger.isDelete){
Set<Id> IdCollect = new Set<Id>();
for(ContentDocument att:Trigger.Old){
    system.debug('--att '+att);
    if(att.id!=null){
        IdCollect.add(att.Id);
    }
}
List<ContentDocumentLink> cdl = new List<ContentDocumentLink>();
cdl = [SELECT Id,LinkedEntityId FROM ContentDocumentLink WHERE ContentDocumentId IN :IdCollect ];
system.debug('ContentDocumentLink ---- cdl '+cdl);
List<Opportunity> oppList = new List<Opportunity>();
for(Opportunity oppy : [SELECT Id,Attachment__c FROM Opportunity where id=:IdCollect]){   
    oppList.add(oppy);
   oppy.Attachment__c = false;
               }
               
update oppList;

}