Android WebView 获取网页数据（html）

1. activity_main.layout

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  
    xmlns:tools="http://schemas.android.com/tools"  
    android:layout_width="match_parent"  
    android:layout_height="match_parent"  
    tools:context=".MainActivity" >  
  
    <WebView  
        android:id="@+id/webView"  
        android:layout_width="fill_parent"  
        android:layout_height="fill_parent"  
        android:layout_centerHorizontal="true"  
        android:layout_centerVertical="true"  
         />  
  
</RelativeLayout>  

2. MainActivity.java

package com.example.webviewhtml;

import android.app.Activity;  
import android.graphics.Bitmap;  
import android.os.Bundle;  
import android.webkit.JavascriptInterface;
import android.webkit.WebView;  
import android.webkit.WebViewClient;  
/** 
 * Dmeo说明: 
 * 当WebView加载网页时获取该网页中的内容. 
 * 参考资料: 
 * http://www.maxters.net/2012/02/android-webview-get-html-source/ 
 */  
public class MainActivity extends Activity {  
   private WebView mWebView;  
     
    @Override  
    protected void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.activity_main);  
        init();  
    }  
    private void init(){  
        mWebView=(WebView) findViewById(R.id.webView);  
        mWebView.getSettings().setJavaScriptEnabled(true);  
        mWebView.addJavascriptInterface(new InJavaScriptLocalObj(), "local_obj");  
        mWebView.getSettings().setSupportZoom(true);  
        mWebView.getSettings().setDomStorageEnabled(true);  
        mWebView.getSettings().setPluginsEnabled(true);  
        mWebView.requestFocus();  
        mWebView.getSettings().setUseWideViewPort(true);  
        mWebView.getSettings().setLoadWithOverviewMode(true);  
        mWebView.getSettings().setSupportZoom(true);  
        mWebView.getSettings().setBuiltInZoomControls(true);  
        mWebView.loadUrl("http://www.baidu.com");  
        mWebView.setWebViewClient(new WebViewClient() {  
            @Override  
            public void onPageStarted(WebView view, String url, Bitmap favicon) {  
                super.onPageStarted(view, url, favicon);  
            }  
  
            @Override  
            public boolean shouldOverrideUrlLoading(WebView view, String url) {  
                view.loadUrl(url);  
                return true;  
            }  
  
            @Override  
            public void onPageFinished(WebView view, String url) {  
                super.onPageFinished(view, url);  
                view.loadUrl("javascript:window.local_obj.showSource('<head>'+"  
                        + "document.getElementsByTagName('html')[0].innerHTML+'</head>');");  
  
            }  
  
            @Override  
            public void onReceivedError(WebView view, int errorCode,  
                    String description, String failingUrl) {  
                super.onReceivedError(view, errorCode, description, failingUrl);  
            }  
  
        });  
    }  
    
    /**
     *  android sdk api >= 17 时需要加@JavascriptInterface
     * @author fei
     *
     */
    final class InJavaScriptLocalObj {  
    	@JavascriptInterface
        public void showSource(String html) {  
            System.out.println("====>html="+html);  
        }  
    }  
}  

3. 在AndroidManifest.xml

增加权限：

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