Flight time Calculator

[cangianos]

Hey everyone!

I've been working on this for two weeks now, and I’m still stuck with no results.

Can anyone help me figure out where I'm going wrong with programming this flight time HH:MM calculator? It's driving me crazy!

I need to add or subtract multiple hours in the HH:MM format, and when I click "=", I should see the result displayed in a read-only textbox.

If someone could provide a corrected .aia file or at least a screenshot of the corrections, that would be absolutely amazing!

Thanks so much for your help—I’m still new to MIT App Inventor and really appreciate any guidance!

Calcolatrice.aia (1.8 MB)

[ABG]

Before diving into the math, I notice you do not take into account

• time zone crossing
• International Date Line crossing.

Yet you call this a flight time calculator?

[marco_tanzi]

Try this extension:

Time Format Extension - Millis to [HH:mm:ss] - [days + HH:mm:ss] - [HH:mm] - [mm:ss] etc

Here is an extension to format the time / duration (millis) in different ways: → [ HH:mm:ss ] → [ days + HH:mm:ss ] → [ HH:mm ] → [ mm:ss ] → etc. This is asked very often and always requires a lot of questions / answers and posts in the forum. (Last here: Creating a Chronometer - #17 by PizzaGuy07) Hence this extension (some of it can also be implemented with the on-board methods, but I want to simplify it:): Version 1 (May 20, 2020): TFormat.aix (5.5 KB) Version 2 (Oct 20, 2021): TForm…

[cangianos]

I don't need any time zone conversion, it's just a calculator to add or subtract multiples flight time HH:MM from a logbook.

For example I put in the read only textbox some values using the keypad and the textbook should show all the calculations and the result.

01:30
+
00:30
+
00,30

Total is 02:30

Its just a simple calculator but my knowledge with programming is still weak and I don't know how to build the code in MIT app inventor.

[TIMAI2]

@cangianos

I need to add or subtract multiple hours in the HH:MM format, and when I click "=", I should see the result displayed in a read-only textbox.

[ABG]

Here's a version using generic blocks and value procedures:
Calcolatrice.aia (1.8 MB)

[cangianos]

Thanks guys, I try your solutions soon and I let you know

[ABG]

If you need a running sum, also see

How do I Save Multiple Items plain in TinyDB (Without Using a List)? I am working with the given code, but it only works for the first item. Please help me fix it

Here's an example without lists. Hopefully it will make students eager to learn lists when they see it in action. [sample run] [blocks] [Designer] listless_checkout.aia (2.9 KB)

[cangianos]

Thanks man is working, now I can study and learn from it.