Multitouch question

Hi!

I want to use a simple multitouch. Simply draw a line dot by dot followed my finger, but not on a canvas.
I searched the extensions but didnt find one that will suffice.
I have 15x10 arrangement in a larger arrangement. All little arrangement contains a canvas for touch recognition. Like a 15x10 pixel screen with very big pixel size :slight_smile: The problem is with touchevent including dragging is that i cant start new touch event until i release the screen. Same for the drag. Cant drag or indicate touch on other canvas even if my finger is already left the firstly dragged one, but still touching the screen.
Is there a solution to this?

maybe this can help you :
http://www.appinventor.org/content/ai2apps/simpleApps/paintPot2

A couple of scale extensions:

Instead of a 15 by 10 grid of Canvases, could you use just one big Canvas and superimpose a 15 by 10 grid on it, deriving rows and columns from x and y values?

Here is a sample project like that ...

I think this can really help you :

http://ai2.appinventor.mit.edu/reference/other/extensionsMultitouch.html

http://ai2.appinventor.mit.edu/reference/other/extensionsGestures.html

https://groups.google.com/g/mitappinventortest/c/oisbuapggog/m/o72bx5Bj00oJ?pli=1

Unfortunately i cant do that, I think.
How do i change the color of that grid? And moreover i have texts on the canvaasses, and to not be enough each canvas is in an arrangement for backgroundimage to keep the text on backgroundimage change, and each of this arragement is in an other arrangement because the arrangement bckgroundcolor is buggy if there is a transparent image in it.
So the screen setup is not so simple.

To understand what i say.


Each rectangle is 2 arrangement and a canvas.

My extension detect touches and multi-touches as well :slightly_smiling_face: .Just register a component and you can detect when the component got touched and how many fingers has been touched, each finger coordinate, and the action that has been made while touching like clicking down,clicking up,dragging,etc..
See here, you can try it:

I'm not up to the challenge of dealing with background images across different screen sizes, so I avoid it.
Here is a sample app where I do everything else on one Canvas, painting with fat lines and using the Canvas text facilities ...
Capture zoomed in Capture zoomed out

HidatoV286.aia (103.0 KB) paint_all_cells

The project grew large for a single screen, so it has been on a back burner for a while.

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Nice. I will look into it. Thank you.

Thank you mohamed. I will try it.

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Hi mohamed!

I tried your extension, but i couldn't figure it out how can i use it for my purpose.
How can i make it to activate touch an canvasses following my dragged finger.
Could you help me with a little describe how or what blocks i have to use, please?
regards,
Zol