Mac Emulator Issues

[EJ Mak]

Hello. I'm an App Inventor noob. I don't have an Android device, and I'm trying to get the emulator and everything else installed on my Mac (running macOS 10.11).

I followed the instructions online, and I'm stuck at the step that directs me to start the emulator:

 

Step 3. Open an App Inventor project and connect it to the emulator

 

"... from App Inventor's menu (on the App Inventor cloud-based software at ai2.appinventor.mit.edu), go to the Connect Menu and click the Emulator option." 

 

However, an emulator isn't opening, and I get an error message. Is this normal behavior on a Mac or does it indicate a problem? If the latter, what else can I try to get it to work?

Note that I tried reinstalling the App Inventor software, but it didn't help. FYI, I used version 3.0 of the installer. 

See attached screenshots which may help to illustrate the issue.

[Evan Patton]

Hi EJ,

The aiStarter program should have started in the background when the installation finished. If you want to confirm that, you can open the Activity Monitor app under /Applications/Utilities and search for aiStarter using the box in the top right. If you don't see an aiStarter process, you should log out and back in again and it should start on login.

Regards,

Evan

[EJ Mak]

Evan,

I have checked the Activity Monitor, and aiStarter is not running. I tried logging out and back in again, and it didn't help.

Other suggestions?

EJ

[Evan Patton]

After completing the installation, there should be a file at /Library/LaunchAgents/edu.mit.appinventor.aiStarter.plist. Do you see this file on your computer? If not, it's possible that the system didn't completely install when you ran the installer. Were there any error or warning messages during the installation? macOS uses this file to launch the aiStarter program at login, so if it's missing that would explain why it doesn't start. You can also manually run the program by going to /Applications/AppInventor/commands-for-Appinventor and running the aiStarter executable there. However, this won't cause it to restart after rebooting, for example.

Regards,

Evan

[EJ Mak]

Evan,

You wrote:

After completing the installation, there should be a file at /Library/LaunchAgents/edu.mit.appinventor.aiStarter.plist. Do you see this file on your computer?

Yes, I do.

Were there any error or warning messages during the installation?

No, not that I recall.

You can also manually run the program by going to /Applications/AppInventor/commands-for-Appinventor and running the aiStarter executable there.

Ah, we might be getting somewhere. When I tried doing so, my Terminal output displayed an error. I pasted the text below. Any idea how to resolve it? I see that the text mentions macOS 10.12, but I'm running 10.11. 

Last login: Mon Oct 21 16:00:44 on console

/Applications/AppInventor/commands-for-Appinventor/aiStarter ; exit;

computerName:~

[0|500] userName$ /Applications/AppInventor/commands-for-Appinventor/aiStarter ; exit;

[4938] Error loading Python lib '/var/folders/2n/rs166rpj4n9_3f8wmmmpdxz00000gn/T/_MEIeejHlD/.Python': dlopen: dlopen(/var/folders/2n/rs166rpj4n9_3f8wmmmpdxz00000gn/T/_MEIeejHlD/.Python, 10): Symbol not found: _getentropy

  Referenced from: /var/folders/2n/rs166rpj4n9_3f8wmmmpdxz00000gn/T/_MEIeejHlD/.Python (which was built for Mac OS X 10.12)

  Expected in: /usr/lib/libSystem.B.dylib

 in /var/folders/2n/rs166rpj4n9_3f8wmmmpdxz00000gn/T/_MEIeejHlD/.Python

logout

Saving session...

...copying shared history...

...saving history...truncating history files...

...completed.

Deleting expired sessions...37 completed.

[Process completed]

[Evan Patton]

Thanks EJ, that does help. Try this version instead.

Regards,

Evan

[EJ Mak]

I tried that new installer, and although the behavior is a little different, I'm still having problems. 

FYI:

• I manually removed the previous version prior to installing the new version. I did this by dragging the /Applications/AppInventor directory to the trash. 
• After installing the new version, when I click the Emulator option in the Connect menu of App Inventor, the resulting dialog box — "Starting... this might take a minute or two" — doesn't ever change or go away after 10+ minutes of waiting.
• My macOS Activity Monitor shows two running processes named aiStarter. Normal? See attached screenshot.

Regards,

EJ

[EJ Mak]

Hello. My issue remains unresolved. Can anyone shed light on a solution? :-)

EJ

[Evan Patton]

Hi EJ,

Do you have the macOS firewall turned on (or a third party firewall)? What happens if you point your browser at http://localhost:8004/ping/?

Regards,

Evan

[EJ Mak]

Evan,

When I go to that URL, I see the following:

{ "status" : "OK", "version" : "3.0" }

Regarding my macOS firewall, yes it is turned on. 

Please advise. :-)

EJ

[Evan Patton]

Hi EJ,

In that case, you'll probably want to make sure that the aiStarter executable is in the list of processes allowed to accept incoming connections. It only listens on localhost, so only programs on your computer (such as your browser) can connect to it. After adding it, you will need to restart the process, which you can either do by logging out and back in again, or by running killall aiStarter in Terminal.app (it should automatically restart).

Regards,

Evan