Restrict the app to one instance

[kittaakos]

Due to this: eclipse-theia/theia#7983

Users will be still able to open multiple browser windows (per sketches) for the same process, but they will NOT be able to start the Pro IDE twice.

[ubidefeo]

The main reason (probably only) to run two instances of the Java IDE was a hack which allowed users to have 2 serial monitors open at once.
In the new IDE each window (sketch) can have its own Serial Monitor

@per1234 do you think it's fair to close this as "won't do"?

[per1234]

If I understand eclipse-theia/theia#7983 correctly (unlikely), Akos's proposal is intended to avoid a bad experience for the user by preventing them from doing something that is not supported (starting two instances of Arduino Pro IDE). That sounds like a very good thing to me.

Even if it's not considered a high priority to work on right now, I would recommend leaving it open for a later time when the higher priority work is finished, or if we find that eclipse-theia/theia#7983 is a regular source of problems for the users.

[ubidefeo]

@per1234 my point was mostly about reasons for opening multiple instances of the IDE.
Since multiple windows/sketches can use multiple Serial Monitor instances, a very common reason for doing so is to have multiple serial monitors connected to multiple boards.
2 instances of this IDE would also conflict because of the gRPC port binding to the CLI.

I cannot see any reason not to restrict it

[per1234]

I cannot see any reason not to restrict it

Same here, so Akos's proposal to "Restrict the app to one instance" is reasonable. So, unless this improvement has already been done, I would leave this open.

[CreativeRobotics]

I routinely work with several microcontrollers at once, working on code that communicates between them. The ability to run two or more instances at once, and have each instance connected to a different communication port for programming and serial debugging is an essential feature for a 'pro' IDE. Having the ability to open multiple sketches, but then having to select different boards and comm ports when dealing with each sketch is a bug in my view.

[mklemarczyk]

I moved to IDE 2.0 only because I can open multiple instances of Arduino IDE. If that feature is gone, I have noting to do here and I can as well use the old Arduino IDE 1.0.

I usually work with multiple boards and projects on Arduino IDE. If you restrict it to one instance it will be a huge drawback. Any other IDE like Visual Studio, or industrial EcoStruxure Control Expert are not having such limitation.

[kittaakos]

If you restrict it to one instance it will be a huge drawback. Any other IDE like Visual Studio, or industrial EcoStruxure Control Expert are not having such limitation.

Thanks for your remark.

For clarification: single instance != single window.

Even if a single instance IDE2 app is running, it will be possible to open multiple windows and work on various sketches just as it is now.

[kittaakos]

Closing. IDE2 has been using the singleInstance config for a long time ago:

arduino-ide/electron/build/patch/backend/main.js

Line 33 in d79bc0d

"singleInstance": true