Android: Cannot change language through the API.

[EL-Dol]

Issue: Android, Cannot change language through the API.

Expected
The language should be set to what I provide, like “es”.
Actual
Uses the default language “en”

Issue confirmed in version: MathCat v0.6.3
Working in version: MathCat v0.5.3

Target OS: Android API 21 (Fire OS & Google Android)
Build OS: Mac (Sonma) & Windows 11
Rust-C: Mac x86_64 (1.80.1) & Windows MSVC (1.80.1),
Build tools: NDK 27, Cargo-NDK, MathCat_C

Message

Hi, I’m having trouble changing the language from the default language “en” (English) on Android trough MathCat_c with the latest MathCat v0.6.3, the default language “en” (English) works fine as it’s correctly parsing the MathML code. It worked fine with the old MathCat v0.5.3 which was before the zipped Rules items. So, I guess there have been more changes under the hood.

I can confirm that unzipping the Language works fine, as I can see the unzipped files in “es” (Spanish). So, I enabled logs on Android to see what’s happening. The summary from the logs is that it seems to be changing between “Auto” and “en” (English) for some reason in “fn find_file” inside prefs.rs, and it loads something from “Rules/prefs.yaml”.

Files

MathCat - logs.txt

[NSoiffer]

I confirmed the problem with 0.6.3, but it doesn't happen in 0.6.4. I haven't published that yet. If you checkout both MathCAT and MathCATForC and make them sibling dirs, then the current versions of the files will build correctly. If this doesn't work for you, I can "publish" 0.6.4, but I'd rather hold off until after I finish triaging issues.

Let me know if I need to publish 0.6.4.

[EL-Dol]

Hi, thanks for your reply.
I've tried using the latest code in MathCat & MathCat_c, and unfortunately it seems to be more broken. Because it can no longer read the default language "en". I was able to trace that issue down to "Add support for wasm with language conductor unpacking." (96f794d), but what inside it is causing the problem is still a mystery. If you want more logs in specific areas or want to run a specific branch, feel free to ask.

It could be connected to that I'm now getting a on Auto/Auto.zip not found error when trying to parse MathML. There is no Auto.zip in the build folder among the Languages from what I can see.

More logs:

Summary: It worked like before until 96f794d after that it stopped responding to parsing requests
add test for fixed bug #272.txt
latest.txt

[EL-Dol]

Found a possible solution a while back, it have been pretty stable during internal usage on iOS, Android & Windows.
Android had a curious issue where the prefs are always reloaded the trying to convert MathML to Text, which causes it to use the default language instead of the selected language. Unsure if this is intended behavior or that some checks simply behaves differently on Android. I did however create a simple load once encasement of the pref loads in the set_preference_files function. You can find the code in my merge request.

[NSoiffer]

There was a problem with the WASM build that sounds vaguely similar to the ones you found. It turns out in my MathCAT demo, I set the preference CheckRuleFiles to None as one of the first things I did. That makes sense since the rule files are compiled in and can't be changed/updated while MathCAT runs, unlike other builds. The default is only to check the prefs.yaml files. For reasons I'm not sure about (perhaps because there is a bug in my fake file system calls for the WASM build), not doing that caused all sorts of weirdness like complaining about Auto/Auto.zip. I modified the MathCAT code to set CheckRuleFiles to None for WASM builds in api_defaults():

        prefs.insert("CheckRuleFiles".to_string(), Yaml::String(
                    (if cfg!(target_family = "wasm") {"None"} else {"Prefs"}).to_string()));    // avoid checking for rule files being changed (40% speedup!) (All, Prefs, None)

Did you try changing the value of CheckRuleFiles on Android? If people can't modify the preference files while it runs, set the value to None via SetPreference.

[EL-Dol]

Haven't tried to change CheckRuleFiles, missed that it's possible to do that. I'll check that next time we are updating MathCat for our projects.