ios - Unable to open new window on successful login Post - Swift -

i new swift. trying build app -

i have login screen , once user types in correct username , password, user redirected new window. have managed http post requests after unable open new window on successful login.

@ibaction func signintapped(sender: uibutton) {    let parameters = "{\"email\": \""+txtusername.text+"\", \"password\": \""+txtpassword.text+"\"}" ;//as dictionary<string, string>      //create url nsurl           let url = nsurl(string: "https://myurl") //change url      //create session object           var session = nsurlsession.sharedsession()      let request = nsmutableurlrequest(url: url!)          request.httpmethod = "post" //set http method post      var err: nserror?       request.httpbody = parameters.datausingencoding(nsutf8stringencoding, allowlossyconversion: true);//nsjsonserialization.datawithjsonobject(parameters, options: nil, error: &err) // pass dictionary nsdata object , set request body             request.addvalue("application/json", forhttpheaderfield: "content-type")            request.addvalue("application/json", forhttpheaderfield: "accept")      //create datatask using session object send data server          var task = session.datataskwithrequest(request, completionhandler: {data, response, error -> void in              println("response: \(response)")                    let strdata = nsstring(data: data, encoding: nsutf8stringencoding)                   println(strdata)                    var err: nserror?          var json = nsjsonserialization.jsonobjectwithdata(data, options: .mutableleaves, error: &err) as? nsdictionary          // did jsonobjectwithdata constructor return error? if so, log error console          if(err != nil) {                       println(err!.localizeddescription)                           let jsonstr = nsstring(data: data, encoding: nsutf8stringencoding)                            println("error not parse json: '\(jsonstr)'")                         }                         else {                          // jsonobjectwithdata constructor didn't return error. but, should still              // check , make sure json has value using optional binding.                    if let parsejson = json {                                  // okay, parsedjson here, let's value 'success' out of                  var success = parsejson["success"] as? int                       println("succes: \(success)")                               }              else {                                   // woa, okay json object nil, went worng. maybe server isn't running?                               let jsonstr = nsstring(data: data, encoding: nsutf8stringencoding)                                     println("error not parse json: \(jsonstr)")                                }          }      }) 

can 1 please give me example. appreciated.

many thanks

this crash log requested @dharmesh kheni

    2015-06-20 16:53:44.028 login[29072:191664] *** assertion failure in -[uikeyboardtaskqueue waituntilalltasksarefinished], /sourcecache/uikit_sim/uikit-3347.44/keyboard/uikeyboardtaskqueue.m:374 2015-06-20 16:53:44.033 login[29072:191664] *** terminating app due uncaught exception 'nsinternalinconsistencyexception', reason: '-[uikeyboardtaskqueue waituntilalltasksarefinished] may called main thread.' *** first throw call stack: (     0   corefoundation                      0x000000010c932c65 __exceptionpreprocess + 165     1   libobjc.a.dylib                     0x000000010e49dbb7 objc_exception_throw + 45     2   corefoundation                      0x000000010c932aca +[nsexception raise:format:arguments:] + 106     3   foundation                          0x000000010cdcf98f -[nsassertionhandler handlefailureinmethod:object:file:linenumber:description:] + 195     4   uikit                               0x000000010d929936 -[uikeyboardtaskqueue waituntilalltasksarefinished] + 151     5   uikit                               0x000000010d3ca952 -[uikeyboardimpl setdelegate:force:] + 473     6   uikit                               0x000000010d67560d -[uiperipheralhost(uikitinternal) _reloadinputviewsforresponder:] + 1002     7   uikit                               0x000000010d67d994 -[uiperipheralhost(uikitinternal) _preserveinputviewswithid:animated:reset:] + 504     8   uikit                               0x000000010d30d531 -[uiviewcontroller _presentviewcontroller:modalsourceviewcontroller:presentationcontroller:animationcontroller:interactioncontroller:completion:] + 623     9   uikit                               0x000000010d30e7ae -[uiviewcontroller _presentviewcontroller:withanimationcontroller:completion:] + 3079     10  uikit                               0x000000010d310701 __62-[uiviewcontroller presentviewcontroller:animated:completion:]_block_invoke + 132     11  uikit                               0x000000010d310625 -[uiviewcontroller presentviewcontroller:animated:completion:] + 229     12  login                               0x000000010c70d420 _tffc5login7loginvc12signintappedfs0_fcso8uibuttont_u_ftgsqcso6nsdata_gsqcso13nsurlresponse_gsqcso7nserror__t_ + 3344     13  login                               0x000000010c70d723 _ttrxfo_ogsqcso6nsdata_ogsqcso13nsurlresponse_ogsqcso7nserror__dt__xfo_itgsqs__gsqs0__gsqs1____it__ + 51     14  login                               0x000000010c70abe1 _tpa__ttrxfo_ogsqcso6nsdata_ogsqcso13nsurlresponse_ogsqcso7nserror__dt__xfo_itgsqs__gsqs0__gsqs1____it__ + 81     15  login                               0x000000010c70d753 _ttrxfo_itgsqcso6nsdata_gsqcso13nsurlresponse_gsqcso7nserror___it__xfo_ogsqs__ogsqs0__ogsqs1___dt__ + 35     16  login                               0x000000010c70d7ba _ttrxfo_ogsqcso6nsdata_ogsqcso13nsurlresponse_ogsqcso7nserror__dt__xfdcb_dgsqs__dgsqs0__dgsqs1___dt__ + 90     17  cfnetwork                           0x000000010f6a600b __49-[__nscflocalsessiontask _task_onqueue_didfinish]_block_invoke + 157     18  foundation                          0x000000010cdf357f __nsblockoperation_is_calling_out_to_a_block__ + 7     19  foundation                          0x000000010cd340b2 -[nsblockoperation main] + 98     20  foundation                          0x000000010cd16774 -[__nsoperationinternal _start:] + 645     21  foundation                          0x000000010cd16383 __nsoqschedule_f + 184     22  libdispatch.dylib                   0x000000010ebc1614 _dispatch_client_callout + 8     23  libdispatch.dylib                   0x000000010eba86a7 _dispatch_queue_drain + 2176     24  libdispatch.dylib                   0x000000010eba7cc0 _dispatch_queue_invoke + 235     25  libdispatch.dylib                   0x000000010ebab3b9 _dispatch_root_queue_drain + 1359     26  libdispatch.dylib                   0x000000010ebacb17 _dispatch_worker_thread3 + 111     27  libsystem_pthread.dylib             0x000000010ef2e6cb _pthread_wqthread + 729     28  libsystem_pthread.dylib             0x000000010ef2c4a1 start_wqthread + 13 ) libc++abi.dylib: terminating uncaught exception of type nsexception 

you can initiate new view controller way when user log in:

if let parsejson = json {         // okay, parsedjson here, let's value 'success' out of          var success = parsejson["success"] as? int         println("succes: \(success)")          dispatch_async(dispatch_get_main_queue()) {             let storyboard = uistoryboard(name: "main", bundle: nil)             let vc = storyboard.instantiateviewcontrollerwithidentifier("yourviewcontrollerid") as! uiviewcontroller             self.presentviewcontroller(vc, animated: true, completion: nil)         }     } 

and don't forget give identifier next view clicking on view controller in storyboard go identity inspector set storyboard id shown in below image:

hope you.