使用 GeolocationPermissions 的 Android WebView

Question

我在这里查看了有关此问题的各种问题，例如:

• Using navigator.geolocation.getCurrentPosition in WebView on Android 2.0+ (PhoneGap related)
• android webview geolocation
• Android: Using html5 to determine geolocation in webview with javascript api

但我还是有点糊涂，我知道我应该从抽象类 WebChromeClient 创建我自己的类。哪个获取位置，但是这个对象究竟如何从那里向 webView 发送地理位置/它们如何通信？

这是我的代码:(这至少是在正确的轨道上吗？)

import android.app.Activity;
import android.app.AlertDialog;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.util.Log;
import android.view.KeyEvent;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.webkit.GeolocationPermissions.Callback;
import android.webkit.JsResult;
import android.webkit.WebChromeClient;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.webkit.GeolocationPermissions;

public class site extends Activity {
WebView engine;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);


    WebViewClient yourWebClient = new WebViewClient() {
        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            if (url.contains("tel:") == true) { 
                Intent intent = new Intent(Intent.ACTION_DIAL, Uri.parse(url)); 
                startActivity(intent); 
            }
            else if(url.contains("visitchicagosouthland") == true) {
                view.loadUrl(url);
            }

//Here is where I create my object, I did this because I only need the location when this
//page is loaded. Could this be part of the problem?

            else if(url.contains("directions.cfm") == true) {
                GeoClient geo = new GeoClient();
                engine.setWebChromeClient(geo);        
                String origin = ""; //how to get origin in correct format?
                Callback call = null;
                geo.onGeolocationPermissionsShowPrompt(origin, call );  
            }
            else {
                /*Intent browserIntent = new Intent(Intent.ACTION_VIEW, Uri.parse("url")); 
                startActivity(browserIntent);*/
            }
        return true;
        }
    };


    engine = (WebView) findViewById(R.id.web_engine);
    engine.getSettings().setJavaScriptEnabled(true);
    engine.getSettings().setBuiltInZoomControls(true);
    engine.getSettings().setSupportZoom(true); 
    engine.getSettings().setJavaScriptCanOpenWindowsAutomatically(true);
    engine.getSettings().setGeolocationEnabled(true);
    engine.setWebViewClient(yourWebClient);
    engine.setScrollBarStyle(WebView.SCROLLBARS_OUTSIDE_OVERLAY);
    engine.loadUrl("http://www.visitchicagosouthland.com/jrudnydev/phone/");
}



@Override
public boolean onCreateOptionsMenu(Menu menu) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.home, menu);
    return true;
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    if ((keyCode == KeyEvent.KEYCODE_BACK) && engine.canGoBack()) {
        engine.goBack();
        return true;
    }
    return super.onKeyDown(keyCode, event);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle item selection
    if(item.getItemId() == R.id.home) {
        engine.loadUrl("http://www.visitchicagosouthland.com/mobile/");
        return true;
    }
    else if(item.getItemId() == R.id.refresh) {
            engine.reload();
            return true;
    }
    else if(item.getItemId() == R.id.stop) {
            engine.stopLoading();
            return true;
    }
    else {
        return super.onOptionsItemSelected(item);
    }
}

}

final class GeoClient extends WebChromeClient {

  @Override
    public void onProgressChanged(WebView view, int progress) {
        // Activities and WebViews measure progress with different scales.
        // The progress meter will automatically disappear when we reach 100%
        //Activity.setProgress(progress * 100);
    }

@Override
public boolean onJsAlert(WebView view, String url, String message, JsResult result) {
    //Log.d(LOG_TAG, message);
    // This shows the dialog box.  This can be commented out for dev
    AlertDialog.Builder alertBldr = new AlertDialog.Builder(null);
    alertBldr.setMessage(message);
    alertBldr.setTitle("Alert");
    alertBldr.show();
    result.confirm();
    return true;
}

@Override
public void onGeolocationPermissionsShowPrompt(String origin, Callback callback) {
// TODO Auto-generated method stub
super.onGeolocationPermissionsShowPrompt(origin, callback);
callback.invoke(origin, true, false);
}

}

我的 android-manifest.xml:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
  package="com.visitchicagosouthland"
  android:versionCode="1"
  android:versionName="1.0">

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<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" />

<application android:icon="@drawable/icon" android:label="@string/app_name">
    <activity android:name=".site"
              android:label="@string/app_name"
              android:theme="@android:style/Theme.NoTitleBar">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

</application>
<uses-sdk android:minSdkVersion="4" />

</manifest> 

Answer 1

当 html 是您自己的时，这很简单。有几种方法，我会给你其中的两种。

使用 GET 的简单方法

想法是在 URL 中发送位置(您可能需要一些编码，但只要它只是数字且没有空格就可以了

对您的 shouldOverridUrlLoading 进行一些编辑

public boolean shouldOverrideUrlLoading(WebView view, String url){
    if (url.needs_geo) //meaning if this is the url that needs the geo location
        url += "?geo=" + your_location;
    view.loadUrl(url);
    return true;
}

在你的 JavaScript 中:

function getParam(name)
{
  name = name.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]");
  var regexS = "[\\?&]"+name+"=([^&#]*)";
  var regex = new RegExp( regexS );
  var results = regex.exec( window.location.href );
  if( results == null )
    return "";
  else
    return results[1];
}

然后

var geo_location = getParam('geo');

使用 WebView.addJavascriptInterface

(我从未尝试过将值从 Java 传递到 JavaScript，但可能也可以)。这个想法是为您的 JavaScript 提供一个 Java 类，可以访问该类以获取您想要传递给 JavaScript 的参数。

在你的 Activity 类中:

public String location; //as an example

    public class SherifJS {
        public String getLocation(){
            return location;
        }
    }
//bla bla

    SherifJS loc = new SherifJS();
    yourWebView.addJavascriptInterface(loc, "locationProvider"); 

在你的 JavaScript 中:

<script type="text/javascript">
        <!--

function sherifJS() {
    document.getElementById("locationHolder").innerHTML =
    window.locationProvider.getLocation();
}

        -->
</script>