aliucord-plugins/guide/06-discord-and-reflection.md

Discord code and reflection

Most interesting plugins patch Discord internals. You need to find the right class and method, then sometimes reach private members.

Upstream:

• docs/documentation/plugin-dev/6_finding_discord_stuff.md
• docs/documentation/plugin-dev/5_reflection.md

Decompile Discord

Pull the APK Aliucord uses (legacy Discord 126.21) and run JADX:

jadx --export-gradle --show-bad-code --fs-case-sensitive \
  --respect-bytecode-access-modifiers \
  --no-inline-methods --no-inline-anonymous --no-inline-kotlin-lambda \
  --output-dir decompiled base.apk

With Aliucord's JADX fork you can also pass --no-generate-kotlin-metadata to drop noisy @Metadata annotations.

A public decompile dump exists at Juby210/discord-jadx. It can be outdated. Prefer a fresh decompile of 126.21 when a symbol is missing.

For live UI ids while Aliucord is running, Developer Assistant helps.

Search strategy that works

1. Reproduce the UI action in Discord.
2. Guess a class name (Widget*, Store*, Model*) and search the decompile.
3. Confirm with nearby strings, resource ids, or call stacks from other plugins.
4. Copy how a similar feature is patched in examples/.

Examples of good "find a peer and copy the target" plugins:

Goal	Look at
Chat list / message UI	Template message embed patch; Vendicated MessageLinkEmbeds, ShowBlockedMessages
Stores / pending reply	Juby210 NoAutoReplyMention
User model fields	Template CoreUser.getUsername patches
Typing	Template StoreUserTyping instead-hook

Prefer access$ methods over reflection

Kotlin/Java compilers emit access$... bridges for private members. Call those first. They are faster and stabler than raw reflection.

WidgetMedia.`access$handlePlayerEvent`(widgetMedia, event)

Reflection when you must

val field = ClassName::class.java.getDeclaredField("fieldName").apply {
    isAccessible = true
}
val value = field.get(instance) // null instance for static

val method = ClassName::class.java.getDeclaredMethod("methodName", Arg::class.java).apply {
    isAccessible = true
}
val result = method.invoke(instance, arg)

Same idea in Java with setAccessible(true).

Cache reflected Field/Method objects. Looking them up on every call is slow.

Obfuscation helpers

Some Discord getters are mangled. Aliucord ships wrappers/extensions for common ones (e.g. MessageEmbedWrapper.title used in the template). Check com.aliucord.wrappers before writing your own reflective accessors.

Next: Build, deploy, publish