package com.idea.unityplugin;import android.os.Bundle;
import android.widget.Toast;import com.unity3d.player.UnityPlayerActivity;public class UnityPlugin extends UnityPlayerActivity {@Overrideprotected void onCreate(Bundle savedInstanceState){super.onCreate(savedInstanceState);}// 传入数据，并通过toast显示public void ShowToast(final String message){runOnUiThread(new Runnable() {@Overridepublic void run() {Toast.makeText(getApplicationContext(), message, Toast.LENGTH_LONG).show();}});}// 返回一个字符串（静态方法）public static String GetInformation(){return "Android Static Msg";}// 返回一个字符串（非静态方法）public String GetInfo(){return "Android Msg";}
}

task makeJar(type: Copy) {delete 'build/libs/unityplugin.jar'from('build/intermediates/bundles/release/')into('build/libs/')include('classes.jar')rename('classes.jar', 'unityplugin.jar')
}makeJar.dependsOn(build)

<manifest xmlns:android="http://schemas.android.com/apk/res/android"package="com.xxxx.androidplugin"android:versionCode="1"android:versionName="1.0"><applicationandroid:allowBackup="true"android:label="@string/app_name"android:supportsRtl="true"><activity android:name="com.XXXX.unityplugin.UnityPlugin"android:label="@string/app_name"><intent-filter><action android:name="android.intent.action.MAIN" /><category android:name="android.intent.category.LAUNCHER" /></intent-filter></activity></application></manifest>

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;public class CallAndroidMethod : MonoBehaviour
{public Button[] buttons;public Text text;private void ShowAndroidToast(){//text.text = "Toast ";using (AndroidJavaClass jc = new AndroidJavaClass("com.unity3d.player.UnityPlayer")){using (AndroidJavaObject jo = jc.GetStatic<AndroidJavaObject>("currentActivity")){text.text = "Toast:";jo.Call("ShowToast", "Android Toast");}}//using (AndroidJavaClass jc = new AndroidJavaClass("com.unity3d.player.UnityPlayer"))//{//    text.text += " Toast1 ";//    using (AndroidJavaObject jo = jc.GetStatic<AndroidJavaObject>("crrentActivity"))//    {//        text.text += " Toast2 ";//        //jo.Call("ShowToast", "Android Toast");//        jo.CallStatic<string>("GetInformation");//        text.text += " Toast3 ";//    }//}
    }private void GetInfomation(){string info = "";using (AndroidJavaClass jc = new AndroidJavaClass("com.unity3d.player.UnityPlayer")){using (AndroidJavaObject jo = jc.GetStatic<AndroidJavaObject>("currentActivity")){text.text = "Static:";info = jo.CallStatic<string>("GetInformation");}}text.text += info;}private void GetInfo(){string info = "";using (AndroidJavaClass jc = new AndroidJavaClass("com.unity3d.player.UnityPlayer")){using (AndroidJavaObject jo = jc.GetStatic<AndroidJavaObject>("currentActivity")){text.text = "Nonstatic:";info = jo.Call<string>("GetInfo");}}text.text += info;}// Use this for initializationvoid Start (){buttons[0].onClick.AddListener(ShowAndroidToast);buttons[1].onClick.AddListener(GetInfomation);buttons[2].onClick.AddListener(GetInfo);}
}