Retrieve firebase data completely before ionic page loads

Hello Everyone, i am a newbie with the ionic framework and am working on a project which connects firebase to an ionic mobile app. I want to know the best way to retrieve data completely from firebase before a particular page in my app loads. This is required because i need to display the retrieved data on the page. However, the page loads before the data is retrieved and it always gives me errors. Can anyone show me the best way to fix this problem. Thank you very much for your support.

You can use an Angular RouteGuard to prevent the page from showing until that data is loaded.

Or you can append ? to the end of the bound variables, so they become optional.

If the operation might be lengthy, you may consider having a loading element or some other indicator. They you could use a boolean and *ngIF to toggle the template

Thank you, i will try that out.