TinyDB how to delete, edit tags. Please help!

[Apex]

Hi I've been struggling with this for over a week. I've tried everything so I ask for help, how can I make it so I have a buttons for deleting someone from the database and updating someones details from the database. The example I've been using is Stephen Zipprich's great example "TinyDB". Thank you all in advanced!

[Apex]

The programming blocks

My Attempt for delete

No idea how to do edit...

[SteveJG]

To start, how about   TinyDB1.ClearTag  tag    where you place the tag with the persons name?  That will delete the person and all the data associated with that person.

To edit, just write over the Existing tag with the new values?

[Apex]

Tried TinyDB1.ClearTag  tag I think.. this is it...

but it still appears on the listpicker came up with the error

Bad arguments to select list item.

The operation select list item cannot accept the arguments: [*empty-string*] [1]

[SteveJG]

...ok...then what you need to do is UPDATE the ListPicker from the TinyDB perhaps. :)   because the person is deleted from the TinyDB.

[Apex]

Sorry but how would I go about doing that? :(

[SteveJG]

Use the TinyDB to populate a List or List of Lists, then assign the ListPicker to the List of Lists .

[Apex]

I had a go.. this is what I though..

It clears the rags but it still doesn't removed the deleted person from the listpicker..

[SteveJG]

to change what is in the ListPicker, you have to change lstpNames.Elements to reflect the tags in the TinyDB.   You can get a list of the current TinyDB tags using the  TinyDB1.GetTags block.    Your ListPicker will not update unless you tell it to      In the code you show, when you add items to list.... block as you do, what you are doing is putting the tag you just deleted back into the List ...don't you think so.... remove that block and see what happens Apex.  You do not want to add to the listpicker, you want to DELETE txtName from the global nameList perhaps?

[simon hewitt]

I am currently creating an app and i had to build a contacts section where i could add. Edit . And delete contacts. When i get home later after work i csn upload my blocks. I have a screen for the add contact. Then a screenfor the edit and delete contact. And thrn a screen for the list of contacts to choose from.

[Scott Ferguson]

See attached blocks image.

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[Apex]

Could you provide me with a example with the global variables and blocks all together? Thank you.

[Apex]

That would be very helpful thanks. 

[Abraham Getzler]

@Apex,  to remove an element from a global list, you need to know its index in the list for the remove item from list block.

You get that from the ListView.SelectionIndex block, in the After Selected event block.

ABG

[Apex]

Can anyone please post a screenshot of the block diagram you are suggesting me to do? Really stuck on this...

[Taifun]

• How to work with Lists by Saj
• How to work with Lists and Lists of lists (pdf) by appinventor.org

Taifun

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