Unity/Native連携

Unity/Native連携/Android連携

Unity/Native連携/Kotlin連携

Unity/Native連携/iOS連携

javaをkotlinにする場合

UnityRenkei.javaを削除し、UnityRenkei.ktを追加する

UnityRenkei.kt

package com.example.mylibrary
import android.util.Log
class UnityRenkei {
    companion object {
        @JvmStatic
        fun teststatic(flag: Boolean): Boolean {
            return flag
        }
    }
    fun test(flag: Boolean): Boolean {
        return flag
    }

    fun testexec() {
        Log.i("test", "testexec")
    }
}

プロジェクト直下のbuild.gradleにbuildscriptを追加

buildscript {
    ext.kotlin_version = "1.8.10"
    repositories {
        google()
        mavenCentral()
    }
    dependencies {
        classpath "com.android.tools.build:gradle:8.1.0"
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
}

plugins {
    id 'com.android.application' version '8.1.0' apply false
    id 'com.android.library' version '8.1.0' apply false
    id 'org.jetbrains.kotlin.android' version '1.8.10' apply false
}

mylibrary/build.gradleを以下の通り修正

plugins {
    id 'com.android.library'
    id 'org.jetbrains.kotlin.android'
}

android {
    namespace 'com.example.mylibrary'
    compileSdk 34

    defaultConfig {
        minSdk 24

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
        consumerProguardFiles "consumer-rules.pro"
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
    kotlinOptions {
        jvmTarget = "1.8"
    }
}
dependencies {
    implementation 'androidx.appcompat:appcompat:1.6.1'
    implementation 'com.google.android.material:material:1.8.0'
    testImplementation 'junit:junit:4.13.2'
    androidTestImplementation 'androidx.test.ext:junit:1.1.5'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.1'
    implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
}

==="NoClassDefFoundError"エラーが出る場合===
エラー詳細
<pre>
Error Unity AndroidJavaException: java.lang.NoClassDefFoundError: Failed resolution of: Lkotlin/jvm/internal/Intrinsics;
Error Unity java.lang.NoClassDefFoundError: Failed resolution of: Lkotlin/jvm/internal/Intrinsics;

対策方法

ProjectSettingsのAndroidのCustomMainGradleTemplateをチェック

Assets/Plugins/Android/mainTemplate.gradle に以下を追加

buildscript {
    ext.kotlin_version = '1.8.0' 
    repositories {
        google()
        mavenCentral()
    }
    dependencies {
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
}

apply plugin: 'com.android.library'
apply plugin: 'kotlin-android'
dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version" // Kotlinランタイムを追加
}

iOS-Unity連携

Unityに記述

#if UNITY_IPHONE
using System.Runtime.InteropServices;
#endif
using UnityEngine;

public class ExampleClass : MonoBehaviour
{
#if UNITY_IPHONE
    [DllImport("__Internal")]
    private static extern bool _testStaticMethod(bool flag);

    [DllImport("__Internal")]
    private static extern bool _testMethod(bool flag);

    [DllImport("__Internal")]
    private static extern void _testExecMethod();
#endif
    void Start()
    {
#if UNITY_IOS && !UNITY_EDITOR
        bool flag = _testMethod(true);
        bool flagstatic = _testStaticMethod(true);
        bool flagfalse = _testMethod(false);
        bool flagstaticfalse = _testStaticMethod(false);
        Debug.Log("flag=" + flag);
        Debug.Log("flagstatic=" + flagstatic);
        Debug.Log("flagfalse=" + flagfalse);
        Debug.Log("flagstaticfalse=" + flagstaticfalse);
        _testExecMethod();
#endif
    }
}

Assets/Plugins/iOS/UnityRenkei.swiftを作成し、以下を貼り付ける。(xcode側では、Libraries/Plugins/iOS/にある。)

import Foundation

@objc public class UnityRenkei: NSObject {
    @objc public static func teststatic(_ flag: Bool) -> Bool {
        return flag
    }

    @objc public func test(_ flag: Bool) -> Bool {
        return flag
    }

    @objc public func testexec() {
        print("testexec")
    }
}

Assets/Plugins/iOS/UnityBridge.mmを作成し、以下を貼り付ける。(xcode側では、Libraries/Plugins/iOS/にある。)

#import <UnityFramework/UnityFramework-Swift.h>

extern "C" {
    // Unityから呼び出せるSwiftメソッドのラッパー
    bool _testStaticMethod(bool flag) {
        bool result = [UnityRenkei teststatic:flag];  // Swiftのstaticメソッドを呼び出す
        NSLog(@"result: %d", result);
        return result;
    }
    bool _testMethod(bool flag) {
        UnityRenkei *renkei = [[UnityRenkei alloc] init];
        bool result = [renkei test:flag];  // Swiftのインスタンスメソッドを呼び出す
        NSLog(@"result: %d", result);
        return result;
    }
    void _testExecMethod() {
        UnityRenkei *renkei = [[UnityRenkei alloc] init];
        [renkei testexec];  // Swiftのインスタンスメソッドを呼び出す
    }
}

出力

flag=True
flagstatic=True
flagfalse=False
flagstaticfalse=False
testexec

参考

https://qiita.com/ohbashunsuke/items/8f3b7c733fc70a180941