Android WebView에서 GPS 사용하기 + 마시멜로우 버전 이상일 경우 권한체크 추가

MainActivity.java

package com.dave.webviewgps;

import android.Manifest;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.webkit.GeolocationPermissions;
import android.webkit.WebChromeClient;
import android.webkit.WebView;
import android.webkit.WebViewClient;

public class MainActivity extends AppCompatActivity {

    private static final String URL_DAUM_MAP = "http://m.map.daum.net/";
    private static final String URL_NAVER_MAP = "http://m.map.naver.com/";
    private static final String TAG = MainActivityTest.class.getSimpleName();
    private static final int MY_PERMISSION_REQUEST_LOCATION = 0;
    private WebView webView;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        webView = (WebView) findViewById(R.id.webview);
    }

    private void initWebView(){
        webView.getSettings().setJavaScriptEnabled(true); // 자바스크립트 사용을 허용한다.
        webView.setWebViewClient(new WebViewClient());  // 새로운 창을 띄우지 않고 내부에서 웹뷰를 실행시킨다.
        webView.setWebChromeClient(new WebChromeClient(){
            @Override
            public void onGeolocationPermissionsShowPrompt(String origin, GeolocationPermissions.Callback callback) {
                super.onGeolocationPermissionsShowPrompt(origin, callback);
                callback.invoke(origin, true, false);
            }
        });
        webView.loadUrl(URL_NAVER_MAP);
    }

    private void permissionCheck(){
        if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED){
            //Manifest.permission.ACCESS_FINE_LOCATION 접근 승낙 상태 일때
            initWebView();
        } else{
            //Manifest.permission.ACCESS_FINE_LOCATION 접근 거절 상태 일때
            //사용자에게 접근권한 설정을 요구하는 다이얼로그를 띄운다.
            ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.ACCESS_FINE_LOCATION},MY_PERMISSION_REQUEST_LOCATION);
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if(requestCode == MY_PERMISSION_REQUEST_LOCATION){
            initWebView();
        }
    }
}