MIT App Invetor 2 do not connect

[Tom Tit Experiment]

Hi!

We have the same problem as a some others writing to the forum.

When we want to connect to AI companion it does not work.

we scan the QR code and in the app the programs code turns up, but then nothing happens

After a while this message comes up

[Tom Tit Experiment]

we use both a PC with win 10 and Chrome

And a Chromebook with crome

we are connected to the same open WiFi network

we have installed the latest version of MIT AI2 Companion

It does not work either on my Samsung S8 smartphon or our Samsung Tablets

/Cecilia

[Chris Ward]

Hello Cecilia

Currently, App Inventor does not support Chrome Books.

From MIT:

This is something that we are looking into supporting, but it is not supported at this time. The Android for Chromebook runtime runs the companion in a separate sandbox that prevents it from reading information such as the Wifi IP address (which is why you get 0.0.0.0). Without a valid IP, the companion will not work. We expect that in the future we will have a solution for Chromebooks that will allow this.

[Chris Ward]

Hi again

Concerning the Samsung devices, they should work. There is a possibility that the problem is to do with the WiFi network. For example, xfinity is unsuitable.

From MIT

When you connect to the Companion you see the QR code displayed on your screen. While the QR code is displayed, your browser is polling our Rendezvous server asking about the IP address of the device you are connecting with. When you scan the code, or enter the code in the Companion, it sends its IP address to the Rendezvous server. The next poll from the browser will get the IP address and dismiss the QR code dialog. So if you see the QR Code dialog go away, then it means your browser has learned the IP Address of your phone. At this point your browser attempts to connect to the Companion on the phone. If this connection is blocked, or is behind a network address translation device (which I believe it is with xfinitywifi) or if both Computer and Phone are behind the same WiFi network *but* the network prohibits devices on it from talking to each other (which I suspect xfinitywifi does), then the browser cannot reach the phone and the whole system hangs at that point.

[Evan Patton]

Just to clarify the statement that Chris posted about Chromebook support. That statement was specifically in regard to running the Companion app on the Chromebook for those Chromebooks that support running Android apps. There should not be any issues with running App Inventor's web interface on a Chromebook and the Companion on a separate device. This is a use case that we often rely on at MIT for workshops and it works well for us.

Is this a commercially configured access point or a home router? Sometimes professionally configured access points (think a hotel or cafe with Wifi) will have host isolation turned on to prevent devices from performing peer-to-peer communication on the network. This helps prevent people snooping on your traffic but unfortunately breaks App Inventor.

Regards,

Evan