Random list and follow up with different commands

Would like to create a app that can do this.

Randomly select an event from a list (e,g, A plus 1, A minus 1, B plus 2, C minus 3)

After the event has been selected, call the value of A,B or C from tinyWebdb and execute the calculation.

Any advise please?

use the pick a random item block to pick a rando item from the list

then split the item using the split at spaces block to get another list

now select the first item (which is A, B or C) and use the TinyWebDB.GetValue block to get the value from TinyWebDB
in the TinyWebDB.GotValue block do the calculation

the documentation is here  

Built-in Blocks Documentation

Component Documentation

A very good way to learn App Inventor is to read the free Inventor's Manual here in the AI2 free online eBook   http://www.appinventor.org/book2 ... the links are at the bottom of the Web page.  The book 'teaches' users how to program with AI2 blocks.

There is a free programming course here http://www.appinventor.org/content/CourseInABox/Intro  and the aia files for the projects in the book are here:  http://www.appinventor.org/bookFiles  

How to do a lot of basic things with App Inventor are described here:  http://www.appinventor.org/content/howDoYou/eventHandling  .

Also do the tutorials http://appinventor.mit.edu/explore/ai2/tutorials.html to learn the basics of App Inventor, then try something and follow the

 Top 5 Tips: How to learn App Inventor

You will not find a tutorial, which does exactly what you are looking for. But doing the tutorials (not only reading a little bit) help you to understand, how things are working. This is important and this is the first step to do.

Taifun

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Trying to push the limits of App Inventor! 

Snippets and Tutorials from Pura Vida Apps by Taifun.         

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Hi Taifun,

Thanks but i think split at spaces does not solve the problem.

To clarify, from the random list, the "events" are all different. Perhaps i should give a better example.

For example in the list, the events are "Take the value of A and subtract from the value of B", "Add the value of C and the value of A", etc (12 other options)

Once the event has been randomly selected, for example "Add the value of C and the value of A", will need to go to Tiny webdb to getvalue of C and A followed by the addition.

I could do the If, do way for 14 times but was wondering if there are better ways.

Please help....

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what about using 2 lists instead?

list 1 to display for the user:

Take the value of A and subtract from the value of BAdd the value of C and the value of A

...

list2:

B - A

C + A

...

and use list 2 for further processing?

use the selection index to get the corresponding item from the second list

and instead the pick a random item block use the random integer block instead to be able to work with the index, see also

How to pick a random item from a list without picking duplicates?

Taifun

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Attached an idea of the list. 

getting value from Webdb cause the value of left, right etc can be view from other screens.

unfortunately with this, after running for a few seconds, the numbers go haywire.

Please help

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this looks like a completely different question?

some tips:

disable the clock for the test

use Do it to debug your blocks, see also tip 4 here

Top 5 Tips: How to learn  App Inventor

Taifun

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Thanks.

one of the Do it result came back as 

Do It Result: com.google.appinventor.components.runtime.Label@440c3a20

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Does that mean there is an error in the code even though it is able to run but not getting the correct data?

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you can't use Do it for local variables

See also Scott's tip How to use 'Do It' to view procedure results, event arguments and local variables.

Taifun

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