Trying to get CheerpJ to actually launch a program

I'm trying to get CheerpJ to run UPRandomizer in a browser, but I can't figure out how to get it to start. It always gives the error "Error: Could not find or load main class com.dabomstew.pkrandom.gui.RandomizerGUI"
Can anyone help me with this?

apignotti•9/20/23, 6:48 AM

Most likely the classpath used for the

cheerpjRunMain

cheerpjRunMain

API call is not correct. I would recommend to follow the Tutorial once to get a better understanding of the tool: https://labs.leaningtech.com/cheerpj2/getting-started/Tutorial

Installation

Run C/C++, Java, and native code in the browser with our WebAssembly developer tools and JavaScript libraries: Cheerp, CheerpJ, and CheerpX

0xBannOP•9/20/23, 6:51 AM

That's uh

0xBannOP•9/20/23, 6:52 AM

That's what I did

apignotti•9/20/23, 6:53 AM

Does the tutorial application work for you?

0xBannOP•9/20/23, 6:53 AM

Nope

apignotti•9/20/23, 6:55 AM

Then there must be some obvious mistake in the page integration. Do you get any error on the dev tools console?

apignotti•9/20/23, 6:56 AM

I am referring to the tutorial application right now, it's quite likely that by debugging that we can understand what the problem is in your own app

0xBannOP•9/20/23, 6:56 AM

wait so just using the tutorial html will result in a separate app being run?

0xBannOP•9/20/23, 6:56 AM

I'm might stupid

apignotti•9/20/23, 6:58 AM

The tutorial HTML is intended to run the specific JAR file referenced in the tutorial itself. This happens via the API

apignotti•9/20/23, 6:59 AM

Please try the whole tutorial from start to finish, so that you can get a better understanding of the tool.

apignotti•9/20/23, 7:00 AM

If your application is normally started via then the API is the correct one

apignotti•9/20/23, 7:00 AM

If, on the other hand, the app is normally started via , you need to use the

cheerpjRunMain

cheerpjRunMain

API

apignotti•9/20/23, 7:00 AM

But the rest of the HTML stays the same

0xBannOP•9/20/23, 7:11 AM

I'm gonna work on this tomorrow

0xBannOP•9/20/23, 8:36 PM

okay I got it to work

0xBannOP•9/20/23, 8:37 PM

Though now I need to figure out how to have it save files to my computer if possible

apignotti•9/20/23, 8:38 PM

You will need to write some integration manually in JavaScript, the browsers are very limited in the access they provide for the filesystem so CheerpJ works with a completely virtualized file system

apignotti•9/20/23, 8:39 PM

For more info about filesystems please see: https://labs.leaningtech.com/cheerpj2/guides/File-System-support

File System support

Run C/C++, Java, and native code in the browser with our WebAssembly developer tools and JavaScript libraries: Cheerp, CheerpJ, and CheerpX

apignotti•9/20/23, 8:39 PM

You will need to save the file on the read-write mount point

0xBannOP•9/20/23, 8:40 PM

It already is able to save to /files/

0xBannOP•9/20/23, 8:40 PM

I just don't know how to get it from there onto my computer

apignotti•9/20/23, 8:41 PM

You can get a Blob object using the API, for example

apignotti•9/20/23, 8:41 PM

It returns a promise that resolve to a Blob

apignotti•9/20/23, 8:42 PM

you can then download it using standard JS techniques

0xBannOP•9/20/23, 8:43 PM

I'm sure that's helpful, though I don't know nearly any JS

0xBannOP•9/20/23, 8:44 PM

I do appreciate it

apignotti•9/20/23, 8:45 PM

Something along this line should work: https://stackoverflow.com/questions/25547475/save-to-local-file-from-blob

Stack Overflow

Save to Local File from Blob

I have a difficult question to you, which i'm struggling on for some time now.
I'm looking for a solution, where i can save a file to the users computer, without the local storage, because local st...

apignotti•9/20/23, 8:45 PM

Being a standard technique you might be able to even find examples more similar to what you want to achieve precisely.

apignotti•9/20/23, 8:46 PM

The keywords are "Blob" and "download"

apignotti•9/20/23, 8:46 PM

in the context of JavaScript, of course

0xBannOP•9/20/23, 8:46 PM

Thanks, man

apignotti•9/20/23, 8:46 PM

I am marking this thread as resolved, for further general questions consider using the #cheerpj2 channel

0xBannOP•9/20/23, 8:47 PM

okiecoke

apignotti•9/20/23, 8:54 PM

One last thing, could you elaborate what part of the tutorial was not clear in the beginning? We are in the process or revisiting the docs and your input might be useful in that regard

0xBannOP•9/20/23, 8:58 PM

I was skimming through it while very tired, so I couldn't tell you

apignotti•9/20/23, 8:58 PM

Ok, thanks for your feedback nonetheless. Take care.