ShowDialogConfirm after press button but process still running not completed

Hi, i added a button into page and i want to show a dialog confirm. When i selected "Yes" the dialog and page is close but the next Actions of Process keep running, this is not completed. Someone can explaint it for me thanks :(

methods: {

          confirmRegistrationWriteOffContract: function() {

            var message = this.get("Resources.Strings.RegistrationWriteOffContractRequestMessage");

            Terrasoft.showConfirmation(message, function(result) { 

              if (result === Terrasoft.MessageBoxButtons.YES.returnCode) {

                this.onSaveButtonClick();

              }

            }, ["yes", "no"], this);

          }

        },

diff: /**SCHEMA_DIFF*/[

            {

                "operation": "merge",

                "name": "Button-be6148b819154a0791eaee8f1635d859",

                "values": {

                    "enabled": true,

                    "click": {

                      "bindTo": "confirmRegistrationWriteOffContract"

                    },

                }

            },