如何使用android webview中的html5地理位置修复“ Position Unavailable”错误？

Question

我正在从外部Web服务器加载html内容时在android webview中构建应用程序。 html内容包含使用地理位置来获取用户当前位置的javascript代码。该代码在Chrome和Firefox中可以正常工作，但在android webview应用中提供了错误。我该怎么办？

我的目标是使用API​​ 20或更高版本的android，并且我试图在android清单文件中包含额外的权限，但是没有任何效果。

这是在外部服务器中带有Javascript代码的HTML代码文件：

//get location
//var a = document.getElementById("demo");
var b = document.getElementById("lat");
var c = document.getElementById("long");
var d = document.getElementById("showDiv");


  var apiGeolocationSuccess = function(position) {

        b.style.display="block";  
        c.style.display="block";
        b.value = position.coords.latitude;
        c.value = position.coords.longitude;


    alert("API geolocation success!\n\nlat = " + position.coords.latitude + "\nlng = " + position.coords.longitude);
};

var tryAPIGeolocation = function() {
    jQuery.post( "https://www.googleapis.com/geolocation/v1/geolocate?key=AIzaSyDCa1LUe1vOczX1hO_iGYgyo8p_jYuGOPU", function(success) {
        apiGeolocationSuccess({coords: {latitude: success.location.lat, longitude: success.location.lng}});
  })
  .fail(function(err) {
    alert("API Geolocation error! \n\n"+err);
  });
};

var browserGeolocationSuccess = function(position) {
  b.value = position.coords.latitude;
  c.value = position.coords.longitude;
  d.style.display = "block"; 

    alert("Browser geolocation success!\n\nlat = " + position.coords.latitude + "\nlng = " + position.coords.longitude);
};

var browserGeolocationFail = function(error) {
  switch (error.code) {
    case error.TIMEOUT:
      alert("Browser geolocation error !\n\nTimeout.");
      break;
    case error.PERMISSION_DENIED:
      if(error.message.indexOf("Only secure origins are allowed") == 0) {
        tryAPIGeolocation();
      }
      break;
    case error.POSITION_UNAVAILABLE:
      alert("Browser geolocation error !\n\nPosition unavailable.");
      break;
  }
};

var tryGeolocation = function() {

  b.style.display="block";  
  c.style.display="block";
  if (navigator.geolocation) {
    navigator.geolocation.getCurrentPosition(
        browserGeolocationSuccess,
      browserGeolocationFail,
      {maximumAge: 50000, timeout: 20000, enableHighAccuracy: true});
  }
};

tryGeolocation();

Android清单文件：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.erosaapp">
    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.ACCESS_GPS" />
    <uses-permission android:name="android.permission.ACCESS_ASSISTED_GPS" />
    <uses-permission android:name="android.permission.ACCESS_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />


    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

MainActivity.java。

/***  ------- */
package com.example.erosaapp;

import android.annotation.SuppressLint;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.webkit.GeolocationPermissions;
import android.webkit.WebChromeClient;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;

public class MainActivity extends AppCompatActivity {

    /*
      WebViewClient subclass loads all hyperlinks in the existing WebView
     */
    public class GeoWebViewClient extends WebViewClient {
        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            // When user clicks a hyperlink, load in the existing WebView
            view.loadUrl(url);
            return true;
        }
    }

    /**
     * WebChromeClient subclass handles UI-related calls
     * Note: think chrome as in decoration, not the Chrome browser
     */
    public class GeoWebChromeClient extends WebChromeClient {
        @Override
        public void onGeolocationPermissionsShowPrompt(String origin,
                                                       GeolocationPermissions.Callback callback) {
            // Always grant permission since the app itself requires location
            // permission and the user has therefore already granted it
            callback.invoke(origin, true, false);
        }
    }

    WebView myWebView;

    @SuppressLint("SetJavaScriptEnabled")
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        String myurl = "https://erosa2019.000webhostapp.com";
        myWebView = (WebView)findViewById(R.id.webView);
        WebSettings webSettings = myWebView.getSettings();

        // Brower niceties -- pinch / zoom, follow links in place
        webSettings.setJavaScriptCanOpenWindowsAutomatically(true);
        webSettings.setBuiltInZoomControls(false);
        webSettings.setDefaultZoom(WebSettings.ZoomDensity.FAR);
        webSettings.setSupportZoom(false);
        webSettings.setDefaultFontSize(20);
        myWebView.setWebViewClient(new GeoWebViewClient());

        // Below required for geolocation
        webSettings.setJavaScriptEnabled(true);
        webSettings.setGeolocationEnabled(true);
        webSettings.setAppCacheEnabled(true);
        webSettings.setDatabaseEnabled(true);
        webSettings.setDomStorageEnabled(true);
        webSettings.setGeolocationDatabasePath(getFilesDir().getPath());

        myWebView.setWebChromeClient(new GeoWebChromeClient());

        myWebView.loadUrl(myurl);
    }

    @Override
    public void onBackPressed() {
        if(myWebView.canGoBack()) {
            myWebView.goBack();
        } else {
            super.onBackPressed();
        }
    }

}

我希望得到提示，要求他们具有纬度和经度，但提示“浏览器地理位置错误！位置不可用”