Detailed blocs functionalities - where do I find them please?

MIT App Inventor Help
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#1

Hi All,

I'm googeling aroud for hours now and can't find the info I'm looking for.

I'd like to build an app (phonebook like) and found lots of examples and tutorials but what I'm missing, in example, is the description of what a LIST or a DICTIONARY bloc can actually do. What are their differences?

In the App Inventor's help, one will find all parameters to works with these blocs but there is no information about what their are ment for.

image

Any info where this to me basic information is to be found please?

difficulty creating an address book
#2

How to Use Lists by Sajal

more Dictionaries advice http://ai2.appinventor.mit.edu/reference/other/json-web-apis.html

#3

Lists collect similar things, indexed by number. Their indices collapse when you remove items.
Lists can be sorted, and can be imported and exported from/to Comma Separated Values (CSV) text for permanent storage in files.

A dictionary is a single thing (object) with named attributes accessed by a (usually text) tag.
Dictionaries be imported and exported from/to JSON text for permanent storage in files.

#4

Thanks for the links :wink:

So I'm still confused on which one to choose to make my phonebook-loke app?

Should I go with a LIST or with a DICTIONARY? What is the right/best way to go please?

I was programming in DBASE3 (Ashton-Tate) 30 years ago and still have the terms "Records", "Fields" and "Indexes" in mind, terms I almost don't see anywhere now. Did it change completely?

#5

For a phonebook I would use TinyDB, with tag/value = contactName/(dictionary of contact details: key=address,homephone,mobile,addressline1,etc.).

TinyDb presents its tagLists alphabetically, which is suitable for a phone book.
Dictionaries are forgiving of missing entries (addressline2,...)

Spoiler Alert: The Gallery is full of phone book apps.

#6

are you familiar with SQL databases?
you could use the built in SQlite database, which is also used by Android itself...
to access it however you will need an extension, for example my sqlite extension https://puravidaapps.com/sqlite.php, there are also other extensions...

the advantage of using a sql database is, you can easily search for a phone number to get the name or you can search for a name to get the phone number...

Taifun

Trying to push the limits! Snippets, Tutorials and Extensions from Pura Vida Apps by icon24 Taifun.

#7

Thank you All.

I'll have a look at the "Gallery" :wink: