No ‘Access-Control-Allow-Origin’ header is present on the requested resource.
Whitelist plugin is already installed.
$httpProvider.defaults.useXDomain = true; is already set to true in .config
already set in config.xml
We are calling https service but getting the above mentioned error.
So go and set this header on the requested resource. It is a problem with the URL you are calling, not with your app.
Alternatively look into using the Service Proxies for a workaround: Ionic CLI Framework: Command-Line Interface to Develop Apps
That helped me issue resolved now.
Awesome. You can mark my answer as “This reply solves the problem” then please.