Dear @Jamail_Serio,
When exactly do you want to refresh it? Do you want an auto-refresh? I can see in your code that you're adding a button, but there already should be a button to refresh List or Library control in the upper right corner of the control:
If you don't have this button - let me know what version of SharePoint you are using, and what version of the app package you currently have in the App Catalog:
