I have created 7 lists with 80 items in them, and for some reason, I cannot call from them. From different screens, I assign a specific "get start value" that is then linked back to the screen with all the lists. Based on the get start value, from 1-80, there are labels that are set to the the index the get start value specifies. But if I do this, there is a runtime error. I will link the aia file, if you guys can help me out. This is for a school computer science project and it is really important. (P.S. I know lists are really inefficient, but they should work, but they are not)
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I loaded your app onto Thunkable, because the MIT AI2 site continues to act like molasses.
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I don't see any blocks in Screen1, the starting screen.
That screen also just has a label, no buttons or ListView to get to the other screens.
That's probably what's causing the error.
It's probably too late to help you on your loading up the Blocks Editor and the Designer with all your data,
which could have been brought in from a spreadsheet export of a csv file and displayed with ListViews or List Pickers.
I can only image the agonizing tedium you went through to type all those blocks.
Ouch.
Glad you got it working.
I advise saving the working .aia and .apk somewhere safe.
Since you say this is for a Computer Science class,
if you will be turning in the source file and want to avoid a face palm
from your instructor when he sees the code,
and if you have the original data in a csv file,
and the time,
I suggest working on a more general version, with the data external from the blocks.
Also think of how to respond to the challenge of adding and removing books
and book categories.
This app, if properly done, does not need more than a dozen or two blocks.
and can be done in a single screen.
See this app in the Gallery for how to search and filter using lists of lists...
ai2.appinventor.mit.edu/?
Also double check your app to make sure it eventually closes all the screens it opens,
otherwise it will run out of RAM.
-- I advise saving the working .aia and .apk somewhere safe.
Since you say this is for a Computer Science class,
if you will be turning in the source file and want to avoid a face palm
from your instructor when he sees the code,
and if you have the original data in a csv file,
and the time,
I suggest working on a more general version, with the data external from the blocks.
Also think of how to respond to the challenge of adding and removing books
and book categories.
This app, if properly done, does not need more than a dozen or two blocks.
and can be done in a single screen.
See this app in the Gallery for how to search and filter using lists of lists...
ai2.appinventor.mit.edu/?
Also double check your app to make sure it eventually closes all the screens it opens,
otherwise it will run out of RAM.
I have the csv file, so what would I do?
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read the file using the file component and convert the text into a list
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how to convert the text into a list depends on the csv file, is it a 1 column or multi column csv table (separated by commas)?
see also
⦁ How to work with Lists by Saj
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/b
There is a free programming course here http://www.appinventor.or
How to do a lot of basic things with App Inventor are described here: http://www.appinventor.org/co
Also do the tutorials http://appinventor.mit.edu/
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.
LMAO SRUJAN I SEE U WERE ALL SO DESPERATE CAUSE MR SIMKANTTEACH CANT TEACH ANYTHING
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