I can't figure out how to separate the tiny DB information into a list

MIT App Inventor Help
1

hi im trying to transfer a drawing made by the user to another screen, i can't figure out how to separate the tiny DB information into a list. can you help?

2

Please download and post each of those event block(s)/procedures here ...
(sample video)

3

here is my current code first one is screen 1 second is screen 2

blocks (1)
blocks (1)1075×496 57.5 KB

blocks
blocks991×851 95.1 KB

cant tell if these downloaded correctly

4

8671fd6f21d58370bbe2ba21a77a8245e8217ebb_2_582x500

  • Don't open Screen1 to return to it. Just close Screen2.
  • If you want to retrieve a list from TinyDB, supply an empty list as default.
  • I can't believe AI2 let you use a '?' as a global variable name. Change it to something text (savedLines) before you invoke the wrath of Murphy's Law.
  • You saved a list in Screen1. Don't steamroll it with a text operation.
  • Use your list items before removing them.
3 Likes
5

thank you for the advice I appreciate it

but there is a problem when I draw a circle, it generates 2 circles 1 the same as the one on the other screen, and 1 that is pixelated rotated 90 degrees to the left or right

blocks (2)
blocks (2)780×674 78.3 KB

6

by the way if I add the 3 remove list blocks it generates 1 scribble circle

7

I missed 2 more bugs in that haystack.

  • You are saving a table, a list of lists. You need to use the 4 items from the first row of the table in drawing a line. I don't see you selecting that row from the table.
  • You should be plotting the points in the selected row, not the entire table.

Use a local variable named 'row' for the selected first item of savedlines, for clarity.

2 Likes
8

thank you for your time, and knowledge! also what do I put in the savedlines var, and local var

9

based on your blocks at post 5th,
do not use while, but use a for range. from 1, to length of list savedlines, step 4.
and no need to remove item from list.

10

thankyou