How to Use the ListPicker

[Kartik_Bhardwaj]

Hi,
I have to use the ListPicker in the User Interface Column to make an app. I need help in coding, inside the element which is inside a ListPicker, if you click it, there should be more elements in the element that is inside the ListPicker. Please help me find any tutorials so that I can learn the ListPicker or please advise me what should I do. Thank you.

[Ken]

A picture of what you are looking to achieve would be helpful.

[Kartik_Bhardwaj]

Hi,
Here is the Photo of my work:

I would like to do this, that when the “English” Button is clicked, then a bunch of years (2020 - 2010) will appear. When I click any of the years, then the top 5 songs of that year will come. That same thing for the “Hindi” Button.
Thank you.

[GC1]

So you are looking for a cascading/nested list.

Follow this example, I did when I was creating the same thing - This two levels.

https://puravidaapps.com/snippets.php#2nestedlistpicker

[Kartik_Bhardwaj]

Thank you so much for your help but I do not understand.
Thank you.

[Ken]

@Kartik_Bhardwaj

I do not understand.

Click the link and it will show you how to setup the blocks:

@GC1

This two levels.

https://puravidaapps.com/snippets.php#2nestedlistpicker

[ABG]

This app looks like a table filter.
Here is a sample app and doc to read …

Build Your Own DB - Part 1

The List Pickers, List Views, etc. all work on the same idea.

[Kartik_Bhardwaj]

Hi,
Actually, I am Getting a RunTimeError when I do the code.
Here it is:

It is saying the same for 2020, 2019, 2018, 2017, 2015, 2014, 2013, 2012, 2011, and 2010. Please make me complete it fast. I need to submit it to a workshop.
Here is the picture of my work:

Please tell me if this is correct.

Thank you.

[TIMAI2]

You are trying to set a single item to an Elements list

[Kartik_Bhardwaj]

Please kindly mark all my mistakes in there and tell me.
Thank you.

[ABG]

You must learn to use tables.
Start by putting your data into a spreadsheet, one row per song, with columns for year, language, singer, title.
Download the spreadsheet as a Comma Separated Values (.csv) file and post it here along with your .aia export.

[Kartik_Bhardwaj]

Please find attached “.aia” file and txt file with songs details. (I wasn’t allowed to upload csv file so changed that to songs.txt)

Thank you.TopSongsDropbox.aia (172.0 KB) Songs.txt (2.9 KB)

[ABG]

Sometimes the easiest way to solve a problem is to generalize the problem and solve the general problem.

Your table was exported with tabs instead of commas, so it had to be loaded with a special conversion procedure:

These blocks will let you pick from any table with headings, based on the headings, up to 5 columns,

TopSongsDropbox_ABG.aia (177.9 KB)
The selection technique filters for exact match by selection, so more work would be needed to filter by range of years, for example.
All blocks:

[Kartik_Bhardwaj]

Thank you so much @ABG. I will download and run the code.

I have started learning MIT App Inventor and trying to understand how coding works.

Request you to please guide me how to learn coding basics.

[Taifun]

@Kartik_Bhardwaj

how to learn coding basics.

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 Our Tutorials! to learn the basics of App Inventor, then try something and follow the Top 5 Tips: How to learn App Inventor

Taifun

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

[Kartik_Bhardwaj]

Many thanks @Taifun

I will follow as advised.