Forge 1.12 + FG3 + Mixins 0.8.2

Update: Forge 1.12 + FG6 + Mixins 0.8.5

build.gradle

buildscript {
repositories {
maven { url ='https://repo.spongepowered.org/repository/maven-public/' }
}
dependencies {
classpath 'org.spongepowered:mixingradle:0.7-SNAPSHOT'
}
}
apply plugin: 'org.spongepowered.mixin'
minecraft {
runs {
client {
jvmArg "-Dfml.coreMods.load=com.example.examplemod.LoadingPlugin"
}
server {
jvmArg "-Dfml.coreMods.load=com.example.examplemod.LoadingPlugin"
}
}
}
repositories {
maven { url ='https://repo.spongepowered.org/repository/maven-public/' }
}
dependencies {
compile "org.spongepowered:mixin:0.8.2"
}
jar {
from {
configurations.compile
.filter { "mixin-0.8.2.jar"== it.name }
.collect { it.isDirectory() ? it : zipTree(it) }
} {
exclude "LICENSE.txt", "META-INF/MANIFSET.MF", "META-INF/maven/**", "META-INF/*.RSA", "META-INF/*.SF"
}
manifest {
attributes([
"FMLCorePluginContainsFMLMod": true,
"ForceLoadAsMod" : true,
"MixinConfigs" : "mixin.examplemod.json",
"TweakClass" : "org.spongepowered.asm.launch.MixinTweaker",
"TweakOrder" : 0
])
}
}

resources/mixin.examplemod.json

{
"compatibilityLevel": "JAVA_8",
"package": "com.example.examplemod.mixin",
"mixins": [
"GuiMainMenuMixin"
]
}

com.example.examplemod.LoadingPlugin

packagecom.example.examplemod;
importnet.minecraftforge.fml.relauncher.IFMLLoadingPlugin;
importorg.spongepowered.asm.launch.MixinBootstrap;
importorg.spongepowered.asm.mixin.Mixins;
importjavax.annotation.Nullable;
importjava.util.Map;
publicclassLoadingPluginimplementsIFMLLoadingPlugin {
publicLoadingPlugin() {
MixinBootstrap.init();
Mixins.addConfiguration("mixin.examplemod.json");
}
@OverridepublicString[] getASMTransformerClass() {
returnnewString[0];
}
@OverridepublicStringgetModContainerClass() {
returnnull;
}
@Nullable@OverridepublicStringgetSetupClass() {
returnnull;
}
@OverridepublicvoidinjectData(Map<String, Object> data) {
}
@OverridepublicStringgetAccessTransformerClass() {
returnnull;
}
}

com.example.examplemod.mixin.GuiMainMenuMixin

packagecom.example.examplemod.mixin;
importnet.minecraft.client.gui.GuiMainMenu;
importorg.spongepowered.asm.mixin.Mixin;
importorg.spongepowered.asm.mixin.injection.At;
importorg.spongepowered.asm.mixin.injection.Inject;
importorg.spongepowered.asm.mixin.injection.callback.CallbackInfo;
@Mixin(GuiMainMenu.class)
publicclassGuiMainMenuMixin {
@Inject(at = @At("HEAD"), method = "initGui")
publicvoidinitGui(CallbackInfoci) {
System.out.println("Hello from GuiMainMenu!");
}
}