HI karthik

Kindly please help to achieve following enhancements in below code

1.)If there are no accounts for a particular alphabet then it should show empty account table with "No Accounts Found" message and also first,prev,next,last buttons should be disabled as there are no records.

2.)Also put a text box component above the table and upon entering 3 or more letters then the corresponding accounts which contains the word should display. If user enters 1 or 2 letters then show error like please enter minimum 3 letters to search. If nothing is entered then no error should be displayed

Apex controller
===========

public class Acc_con_Opp_Details
{
    //list of collection of the wrapper class object
    public list<accountwrapper> actwrap           {set;get;}
    //list of collection of Account,contact and opportunity objects
    public list<Account>        accounts          {set;get;}
    public list<Account>        acts              {set;get;}
    public list<opportunity>    opts              {set;get;}
    public list<opportunity>    sopts             {set;get;}
    public list<contact>        cnts              {set;get;} 
    public list<contact>        snts              {set;get;}
   public string                searchstring      {get;set;}//used in searching account records 
    public boolean oppbox                         {set;get;}//used as check box for opportunity 
    public boolean conbox                         {set;get;}//used as check box for contact
    public boolean flag1                          {set;get;}//used in account page block  
    public boolean flag2                          {set;get;}//used in contact page block 
    public boolean flag3                          {set;get;}//used in opportunity page block
    public boolean checkallflag                   {set;get;}//used for header check box
    public Boolean oppError                       {set;get;}//used to display opportunity error
    public Boolean conError                       {set;get;}//used to display contacts error
    public Boolean oppboxError                    {set;get;}//used to dispaly opportunity error
    public Boolean conboxError                    {set;get;}//used to display contacts error   
    public list<String> AlphaList                 {get; set;}//collection of alphabets
    public String AlphaFilter                     {get; set;}//used to filter alphabets
    private String Query;
    //this variables are used for pagination purpose
    private integer totalRecs = 0;//stores no.of total records   
    private integer index = 0;//used for tracking offset
    private integer blockSize =5;//for setting size of page
    private String sortDirection = 'ASC';
    private String sortExp = 'Name';
    public Map<String, String> mapAlpha{get; set;}
 
    //in this constructor we are setting values to boolean variables
    public Acc_con_Opp_Details()
    {
    flag1=true;
    flag2=false;
    flag3=false;
    oppError=false;
    conError=false;
    oppboxError=false;
    conboxError=false;    
    checkallflag = false;
    totalRecs = [select count() from Account];//returns total no.of account records 
    getactwrap();//calling getactwrap method.
    AlphaList = new list<String> {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'Other', 'All'};
    if (apexpages.currentpage().getparameters().get('alpha') == null) {
        AlphaFilter = 'All';
    } else {
        AlphaFilter = apexpages.currentpage().getparameters().get('alpha');
    }
    }
    public String sortExpression
    {
      get
      {
         return sortExp;
      }
      set
      {
        //if the column is clicked on then switch between Ascending and Descending modes
        if (value == sortExp)
          sortDirection = (sortDirection == 'ASC')? 'DESC' : 'ASC';
        else
          sortDirection = 'ASC';
          sortExp = value;
      }
    }

    public String getSortDirection()
    {
       //if not column is selected 
       if (sortExpression == null || sortExpression == '')
           return 'ASC';
       else
          return sortDirection;
    }

    public void setSortDirection(String value)
    {  
        sortDirection = value;
    }
    //this method displays first five records
    public void beginning()
    {    
        flag2 = false;
        flag3 = false;
        oppbox=false;
        conbox=false;
        conboxError=false;    
        oppboxError=false;
        checkallflag=false;
        index = 0;
        getactwrap();
    }
    //this method displays prevoius records
     public void previous()
    {    
        flag2 = false;
        flag3 = false;
        oppbox=false;
        conbox=false;
        conboxError=false;    
        oppboxError=false;
        checkallflag=false;
        index = index-blockSize;
        getactwrap();
    }
    //this method displays next records
   public void next()
    {    
        flag2 = false;
        flag3 = false;
        oppbox=false;
        conbox=false;
        conboxError=false;    
        oppboxError=false; 
        checkallflag=false;
        index = index+blockSize;
        getactwrap();
    }
    //this method displays last remaining records
 public void end()
    {    
        flag2 = false;
        flag3 = false;
        oppbox=false;
        conbox=false;
        conboxError=false;    
        oppboxError=false;
        checkallflag=false;
        index = totalrecs - math.mod(totalRecs,blockSize);
        getactwrap();
    }  
    //this variable is used to enable or disable first and previous buttons
 public boolean prev{get
    {
        if(index == 0)
        return true;
        else
        return false;
    }  set;}
    //this variable is used to enable or disable next and last buttons
 public boolean nxt{get
    {
        if((index + blockSize) > totalRecs)
        return true;
        else
        return false;
    }   set;}
    //used to display opportunities and contacts w.r.t selected accounts
    public void  submit()
    {
        
        acts=new list<Account>();
        List<Boolean> acflagList = new List<Boolean>();
        for(accountwrapper aw:actwrap)
           {
            if(aw.acflag){
                acts.add(aw.acc);
                acflagList.add(aw.acflag);
           } 
        }
        
         if(acflagList.isEmpty()) {
           if(oppbox)
               oppboxError=true;
           if(conbox)
               conboxError=true;
           flag2=false;
           flag3=false;
           oppError=false;
           conError=false;
        } 
        else 
        {
            oppboxError=false;
            conboxError=false;
        }
        
        //if we select contact check box,then it displays contacts for selected accounts 
      if(conbox)
      {
      
              snts=[select id,lastName,Department,account.name from contact where accountid IN:acts];
              if(snts.size()>0)
              {
                  flag3=true;
                  conError=false;
              }
              else
              {
                  for(accountwrapper aw : actwrap) {
                      if(aw.acflag) {
                          flag3=true;
                          conError = true;
                      }
                          //ApexPages.addmessage(new ApexPages.message(ApexPages.severity.WARNING,'contact records are not found for selected Accounts.'));
                    }
              }
         } else {
             flag3 = false;
         }
        //if we select opportunity check box,then it displays opportunities for selected accounts
      if(oppbox)
        {
              opts=[select id,name,stageName,leadsource,account.name from opportunity where accountId IN:acts];
              if(opts.size() >0)
              {
                  flag2=true;
                  oppError=false;
              }
              else       
              {    
                    for(accountwrapper aw : actwrap) {
                      if(aw.acflag) {
                          flag2=true;
                          oppError = true;
                      }
                          //ApexPages.addmessage(new ApexPages.message(ApexPages.severity.WARNING,'opportunity records are not found for selected Accounts.'));
                    }
              }
        } else {
            flag2 = false;
        }
        
    }
   //it hides contacts and dispalys opportunitites on uncheck of contact check box
   //This method uses a simple SOQL query to return a List of Accounts
    public void getactwrap() {
        String QueryIf = '';
        string sortFullExp = sortExpression  + ' ' + sortDirection;
        if (AlphaFilter == null || AlphaFilter.trim().length() == 0) {
            AlphaFilter = 'All';
        }
        
        Query = 'SELECT Id, Name, phone ' + ' FROM Account'; 
        
        if (AlphaFilter == 'Other') {
            QueryIf = QueryFor(QueryIf, '(' + 'Name' + ' < \'A\' OR ' + 
                                    'Name' + ' > \'Z\') AND (NOT ' + 
                                    'Name' + ' LIKE \'Z%\') ');
        } else if (AlphaFilter != 'All') {
            QueryIf = QueryFor(QueryIf, '(' + 'Name' + ' LIKE \'' + String.escapeSingleQuotes(AlphaFilter) + '%\')' );
        }
        
        Query += QueryIf;
        Query += ' ORDER BY ' + sortFullExp + ' LIMIT : blockSize OFFSET : index';
        accounts = Database.Query(Query);
        actwrap=new list<accountwrapper>();
       // As each Account is processed we create a new accountwrapper object and add it to the wrapper class(accountwrapper) list.
         for(account a:accounts)
        {
            actwrap.add(new accountwrapper(a));
        }
        flag2=false;
        flag3=false;
        oppbox=false;
        conbox=false;
        conboxError=false;    
        oppboxError=false;
        checkallflag=false;
    }
    public String QueryFor(String Q, String C) {
        if (Q == '') {
            return ' WHERE ' + C;
        } else {
            return Q + ' AND ' + C;
        }
    }
    public void Hideandshowopp()
    {
     
        if(oppbox)
          {     
              submit();
          } else {
              flag2 = false;
              oppboxError=false;
          }
         
    }
   //  it hides opportunities and dispalys contacts on uncheck of opportunities check box 
     public void HideandshowCon()
    {
        if(conbox)
         {    
              submit();
          } else {
              flag3 = false;
              conboxError=false;    
       
          }
         
    }
   
    public void Hideandshowoppcon() {
        Hideandshowopp();
        Hideandshowcon();
    }
    
    
    // this method  uses dml operation to edit the existing opportunities values or to insert new oppt values
    public void saveopps()
    {
        list<opportunity> opps=new list<opportunity>();
        opps.addAll(opts);
        upsert opps;
    }
    //his method  uses dml operation to edit the existing contact values or to insert new contact values
    public void savecons()
    {
       cnts = new list<contact>();
        cnts.addall(snts);
        upsert cnts;
    }
     //used for searching account records dynamically
     public void search(){  
     string searchquery='select name,id from account where name like \'%'+searchstring+'%\' Limit 20';  
     accounts= Database.query(searchquery);  
   }  
 //This is wrapper class which is collection of other class instances
  //here  wrapper class contains both the standard salesforce object Account and a Boolean value acflag   
 public class accountwrapper{
        public account acc{set;get;}
        public boolean acflag{set;get;}
             //In this contructor When we create a new accountwrapper object we pass a Account that is set to the acc property.
             // We also set the boolean value to false
        public accountwrapper(account a){
            acc=a;
            acflag=false;
        }
        
    }

}

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