Close dialog on complete/cancel

The problem

I have a problem trying to close a dialog box.

Details

1. Page /sites/site1/Pages/Dashboard.aspx opens a dialog box using SharePoint Modal API (SP.UI.ModalDialog.showModalDialog)

2. The dialog opens the url /sites/site1/Lists/OutputRequests/NewForm.aspx

3. K2 redirects the page to https://k2dev.idmdevnet.local/Runtime/Runtime/Form.aspx?_Name=...

When the page is successfully submitted or canceled we get "Form submitted successfully" and then the user has to manually close the dialog, which we wanted to be done automatically.

- The SharePoint APIs are not longer available since the page is not in the K2 application/domain

- window.close and window.parent.close will throw "Scripts may close only the windows that were opened by it."

- the close window rule doesn't close the dialog

Specs

K2 4.16060.2000.1

SharePoint 2013 15.0.4849.1000

Related threads

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http://community.k2.com/t5/K2-blackpearl/SmartForm-rule-action-quot-close-the-browser-window-quot-leaves/td-p/79298

Close SmartForm Window

http://community.k2.com/t5/K2-blackpearl/Close-SmartForm-Window/td-p/59409

Close SharePoint 2013 Modal Dialog box with Cancel Button

http://community.k2.com/t5/K2-blackpearl/Close-SharePoint-2013-Modal-Dialog-box-with-Cancel-Button/td-p/80305