ios - Call initializer from a Super Super Class in Swift? -

i have subclass of uitableviewcontroller:

class classa : uitableviewcontroller {      // mark: init     convenience init() {         self.init(style: .grouped)     }      convenience init(form: formdescriptor) {         self.init()         self.form = form     }      override init(style: uitableviewstyle) {         super.init(style: style)     }      override init(nibname nibnameornil: string!, bundle nibbundleornil: nsbundle!) {         super.init(nibname: nibnameornil, bundle: nibbundleornil)         baseinit()     }      required init(coder adecoder: nscoder) {         super.init(coder: adecoder)         baseinit()     }     } 

i made subclass of classa:

class classb : classa {    override init(style: uitableviewstyle) {     super.init(style: style)   }    convenience init() {     self.init(style: .grouped)     self.form = getform()   }    required init(coder adecoder: nscoder) {       fatalerror("init(coder:) has not been implemented")   } } 

i tried init classb initializer uitableviewcontroller uses uitableviewstyle. when running code get:

fatal error: use of unimplemented initializer init(nibname:bundle:)

how can init classb style property uitableviewcontroller?

put code in classb:

override init(nibname nibnameornil: string!, bundle nibbundleornil: nsbundle!) {     super.init(nibname: nibnameornil, bundle: nibbundleornil) } 

then able init classb follows:

let b = classb(style: uitableviewstyle.grouped)