asp.net mvc 4 - ViewModel List object return Null on HTTPPost -

i posting form server, values null.

model:

public class rdetailsviewmodel {     public rdetailsmaster rdetailsmaster { get; set; }     public etransaction etransaction { get; set; } }  public class rdetailsmaster {     [required]     public list<qe_dropdown_mst> master_eq { get; set; }      [required]     public list<qe_dropdown_mst> master_basis { get; set; }      [required]     public list<qe_dropdown_mst> master_te { get; set; }      [required]     public list<qe_dropdown_mst> master_alop { get; set; }      [required]     public list<qe_dropdown_mst> master_risk { get; set; }      [required]     public list<qe_dropdown_mst> master_excess { get; set; }      [required]     public list<qe_dropdown_mst> master_ctype { get; set; }  } 

controller:

 [httppost]     public actionresult rdetails(rdetailsviewmodel objr)             {        return view();     } 

my view :

 @model qms_erater.viewmodels.rdetailsviewmodel  @{     viewbag.title = "rdetails";   } <script src="~/scripts/ear/rdetails.js"></script> @using (html.beginform("rdetails", "rdetails", formmethod.post)) {    <h2>rdetails</h2> <div class="well well-sm">     <div id="divdetail101" runat="server">         <div class="row">             <div class="col-sm-4">                 <span style="vertical-align: top; color: red">*</span> eq :             </div>             <div class="col-sm-3">                 @html.dropdownlistfor(m => m.etransation.eq, new selectlist(model.rdetailsmaster.master_eq, "value", "description"), "--select--", new { style = "width: 100%;" })             </div>             <div class="col-sm-2">                 <span style="vertical-align: top; color: red">*</span> on first loss basis :             </div>             <div class="col-sm-3">                 @html.dropdownlistfor(m => m.etransation.basis, new selectlist(model.rdetailsmaster.master_basis, "value", "description"), "--select--", new { style = "width: 100%;" })             </div>             <div class="col-sm-4">                 <span style="vertical-align: top; color: red">*</span> terrorism :             </div>              <div class="col-sm-3">                 @html.dropdownlistfor(m => m.etransation.is_te, new selectlist(model.rdetailsmaster.master_te, "value", "description"), "--select--", new { style = "width: 100%;" })             </div>             <div class="col-sm-2">                 <span style="vertical-align: top; color: red">*</span> alop :             </div>              <div class="col-sm-3">                 @html.dropdownlistfor(m => m.etransation.is_alop, new selectlist(model.rdetailsmaster.master_alop, "value", "description"), "--select--", new { style = "width: 100%;" })             </div>              <div class="col-sm-4">                 <span style="vertical-align: top; color: red">*</span> wet risk :             </div>              <div class="col-sm-3">                 @html.dropdownlistfor(m => m.etransation.is_risk, new selectlist(model.rdetailsmaster.master_risk, "value", "description"), "--select--", new { style = "width: 100%;" })             </div>         </div>     </div>      <input type="submit" value="submit" />  </div>     

}

when trying call post method objr return null value list objects. appreciated. in advance!