Detect user input

[TIMAI2]

In which case:

Any good reason because my aia does not open an existing screen?

Try this: TestNestingScreens_revised.aia (15.5 KB) Screen1 remains open to stop it be re-initialised when returning from Main. (Hence the use of tinydb on Screen1 and Main) All other screens are closed when another screen is opened. To test, you will need to compile to an apk for this to work properly.

[ChrisWard]

I think Virtual Screens would suit your App better.

When we define virtual screens, we use one 'real' App Inventor Screen (most often Screen1). Screen-sized Vertical Arrangements on it are displayed/hidden as required - they are the Virtual Screens. This is generally a better approach for multi-screen Apps, they share data without having to "pass" it between screens and it also reduces code duplication, making the App more efficient and the code easier to follow if you have to return to it at a later date.

So, instead of separate "houses", virtual screens are "rooms" of the same "house".

Note though, you don't need 1 Screen (or Virtual Screen) per document. The User can only view one screen, so that screen can be defined as a viewer for all of the documents. You could have one Virtual screen each for the document type and any unique components that screen may require.

[tostas]

Thank you! once again.

[tostas]

I understand what you say, I had read the warning about multiple screens, I have a web viewer going through many links, I think it would be better organized if it had multiple screens.
I have more things in the app that I think are fine for now, if I need to change anything in the app or if there are problems, I will use these solutions. Thank you!