Fix crash when opening settings after upgrading from previous version and having old theme selected

[mzorz]

Closes #1772

Fix

What was happening
ListPreference crashes on resume because a deprecated theme value stored in SharedPreferences is an invalid index for the newly shortened resource array.

User selects 'Auto' theme (value 2) before it was deprecated.
The user's preference is stored in SharedPreferences. In an older version, the theme options included 'Auto' which corresponded to a value that is now invalid or points to a different entry.

The 'Auto' theme was removed in commit c43d0ad. The array_theme_values for API 29+ now only contains 3 items (0, 1, 2), but the user's stored value might be 3 (System) or 2 (Auto, which is now System).

0 1 2

Fix:
Added a workaround to comply with existing saved preference where the options array included more values than the new array has in newer versions, so this ListPreference extension checks for bounds to prevent IOBException and defaults to the system value

Test

1. download the previous version of Simplenote and install it on your phone 2.34 https://github.com/Automattic/simplenote-android/releases/tag/2.34
2. login with an account with data
3. go to settings and select Theme "System" (fourth option)
4. exit settings
5. now create a release build on this branch and update the app on the same device:
   go to Build -> Generate Signed App Bundle or APK, choose APK, then populate the fields with the secret store data in gradle.properties, or ping me for to DM you a signed APK.
6. observe you can go to settings and it doesn't crash

In the following video I show you all 3 updates:

1. old version 2.34 working, saving to use the fourth theme option.
2. then installing 2.36 and attempting to go to settings -> observe it crashes
3. then installing the fix (built a signed release version locally), opening settings and it works.

Screen.Recording.2025-10-17.at.7.11.36.PM.mov

Review

Release

[dangermattic]

	1 Warning
⚠️	Class SafeThemeListPreference is missing tests, but unit-tests-exemption label was set to ignore this.

Generated by 🚫 Danger

[wpmobilebot]

📲 You can test the changes from this Pull Request in Simplenote Android by scanning the QR code below to install the corresponding build.

	App Name	Simplenote Android
	Build Type	Debug
	Commit	f5b1f07
	Direct Download	simplenote-android-prototype-build-pr1778-f5b1f07-0199f335-5204-4293-b8f1-ac52bf6d3d89.apk

[zwarm]

I left a single comment with regards to getValue possibly being null. Otherwise the code looks good.

[zwarm]

@mzorz - is there a change that getValueI() can return null? I'm can't tell if findIndexOfValue(value) handles that case.

[mzorz]

Great observation! exactly that case is handled in findIndexOfValue, so no worries 👍

[mzorz]

Thank you for your review @zwarm ! 🙏