ios - UIAlertView UITextField showing black border -

i creating uialertview textinput, though clear background , giving border colour showing black border.

uialertview *alerttorename=[[uialertview alloc]initwithtitle:@"dropbox export" message:@"export as:" delegate:projectdetailsreference cancelbuttontitle:nil otherbuttontitles:@"ok", nil];             alerttorename.alertviewstyle = uialertviewstyleplaintextinput;             [[alerttorename textfieldatindex:0] settext:[appdelegate.projectname stringbydeletingpathextension]];             uitextfield *textfield = [alerttorename textfieldatindex:0];             [textfield setbackgroundcolor:[uicolor clearcolor]];             textfield.borderstyle=uitextborderstyleroundedrect ;             textfield.layer.bordercolor=[[uicolor lightgraycolor]cgcolor];             textfield.layer.borderwidth = 0.1f;             textfield.layer.cornerradius = 5;             textfield.clipstobounds      = yes;              alerttorename.tag=233;             [alerttorename show]; 

refer example, uialertcontroller :

uialertcontroller *alertcontroller = [uialertcontroller                 alertcontrollerwithtitle:alerttitle                                  message:alertmessage                           preferredstyle:uialertcontrollerstylealert];  [alertcontroller addtextfieldwithconfigurationhandler:^(uitextfield *textfield)  {        textfield.placeholder = nslocalizedstring(@"loginplaceholder", @"login");  }];  [alertcontroller addtextfieldwithconfigurationhandler:^(uitextfield *textfield)  {        textfield.placeholder = nslocalizedstring(@"passwordplaceholder", @"password");        textfield.securetextentry = yes;  }]; 

the values of text field can retrieved in ok action handler:

uialertaction *okaction = [uialertaction   actionwithtitle:nslocalizedstring(@"ok", @"ok action")   style:uialertactionstyledefault   handler:^(uialertaction *action)   {     uitextfield *login = alertcontroller.textfields.firstobject;     uitextfield *password = alertcontroller.textfields.lastobject;   }]; 

for more info uialertcontroller, refer link.