How do you tell CloudDB if the username or password is incorrect/ not in the database

[AppBuilder6571]

How do you tell CloudDB if the username or password is incorrect/ not in the database?
This is what I have so far.

Thanks In Advance!

[AppBuilder6571]

And no, this is not all that I have on the app. lol

[Alpha2020]

For a login system you should also have an register system. For a registration system you can use this block.

• First it will check the username already exists or not.
• If already exists then it will show a message.
• If not it will create a tag named the username and value as password.

And for the Login System you can use this blocks.

• First it will check if the username exists or not.
• If it is not existing then it will show a message.
• If exists, then it will check if the password is correct or not.
• If correct will show a message that "Login Successful".
• If not it will also show a message.

Is it ok?

[TIMAI2]

Added to Login FAQ

FAQ Section: Login

A complete login example using a Fusion Table (obsolete) as simple as possible - Taifun A Login Template by eixerits Login Using FireBase DB - TimAI2 Register and Login using Firebase Authentication for your app - TimAI2 Login with Google Oauth - Diego Barreiro Login with TinyDB, single user - ABG How to Make A ‘Remember Me’ checkbox - Alpha2020 Login/Register using Google Sheets & simpleCrypto - TimAI2 Login/Register System for CloudDB - Alpha2020 How to Logout of AI2 - @Susan_Lane

[AppBuilder6571]

Advice on how to do it on the same screen? My login and register is on the same screen.

[TIMAI2]

Use vertical arrangements as virtual screens, setting their visibility on and off to emulate real screens. organise your blocks in "screen" columns to help you keep track.

Read this for more help:

Use different screens wisely

• Before starting to create another screen, first you should think about is it really necessary? 
• See also Building apps with many screens and SteveJG's post about advantages/disadvantages, because in only one screen you also can use vertical arrangements to simulate different screens, just set the arrangements to visible = true/false as needed... 
• See also Martyn_HK's example about how to use Tabs in App Inventor and another example from Cyd. and my Tabbed Screens Demo

If you decided to use different screens, then you should switch them correctly, else you will run out of memory after a while...      
The recommended method of switching screens in App Inventor

(Thanks Taifun)

 

Also see demo: multiscreen.aia

 

[TIMAI2]

See also here for some ideas about using virtual screen for register/login:

Register and Login using Firebase Authentication for your app

[firebaselogo] Seen several people asking about this, so decided to write it up. I have included email verification as well. Registration & Login with Firebase Authentication

[RAVEN_KYLE]

But how do you tell the app that if it is incorrect it doesn't let it go to home?

[TIMAI2]

@RAVEN_KYLE

how do you tell the app that if it is incorrect it doesn't let it go to home?

Explain in more detail what you mean, or what you are trying to achieve....

[RAVEN_KYLE]

Oh Figured out that question, but if both the username and password is wrong do both alerts come in together? Or can only one be notified.

[TIMAI2]

Follow the logic in the blocks

• if the username does not exist, then you will get the username notification (only)
• if the username does exist, then the password is checked.
• if the password does not exist (is incorrect), then you get the password notifier (only)

There is no point in displaying the password notifier if the username does not exist