package com.example.helloweb;import android.app.Activity;import android.app.ActionBar;import android.app.Fragment;import android.content.Context;import android.os.Bundle;import android.view.LayoutInflater;import android.view.Menu;import android.view.MenuItem;import android.view.View;import android.view.ViewGroup;import android.os.Build;import android.webkit.WebChromeClient;import android.webkit.WebView;import android.webkit.WebSettings;import android.webkit.WebStorage.QuotaUpdater;public class MainActivity extends Activity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        // 为了支持HTML5使用数据库(sqlite)的本地存储        String databasePath = getApplicationContext().getDir("database", Context.MODE_PRIVATE).getPath();                if (savedInstanceState == null) {            PlaceholderFragment fragment = new PlaceholderFragment();            fragment.setDatabasePath(databasePath);                        getFragmentManager().beginTransaction()                    .add(R.id.container, fragment)                    .commit();        }    }    @Override    public boolean onCreateOptionsMenu(Menu menu) {                // Inflate the menu; this adds items to the action bar if it is present.        getMenuInflater().inflate(R.menu.main, menu);        return true;    }    @Override    public boolean onOptionsItemSelected(MenuItem item) {        // Handle action bar item clicks here. The action bar will        // automatically handle clicks on the Home/Up button, so long        // as you specify a parent activity in AndroidManifest.xml.        int id = item.getItemId();        if (id == R.id.action_settings) {            return true;        }        return super.onOptionsItemSelected(item);    }    /**     * A placeholder fragment containing a simple view.     * 被实例化，作为子UI的类     */    public static class PlaceholderFragment extends Fragment {        String databasePath;                public PlaceholderFragment() {            }                // 拿到MainActivity生成的数据库路径        public void setDatabasePath(String databasePath){            this.databasePath = databasePath;        }        @Override        public View onCreateView(LayoutInflater inflater, ViewGroup container,                Bundle savedInstanceState) {                        View rootView = inflater.inflate(R.layout.fragment_main, container, false);            // 通过IDE在子UI里拖进去一个webView,所以这里从rootView里查找            WebView  webView = (WebView)rootView.findViewById(R.id.webView1);            webView.setWebChromeClient(this.makeWebChromeClient());                        WebSettings webSettings = webView.getSettings();                   webSettings.setJavaScriptEnabled(true);            webSettings.setDatabaseEnabled(true);            webSettings.setDatabasePath(this.databasePath);                        // 可以加载本地和网络的资源，加载网络资源需要配置权限            //webView.loadUrl("http://www.csdn.net/");            webView.loadUrl("file:///android_asset/demo.html");               return rootView;        }                private WebChromeClient makeWebChromeClient(){            return new WebChromeClient(){                @Override                public void onExceededDatabaseQuota(                    String url,                    String databaseIdentifier,                    long currentQuota,                    long estimatedSize,                    long totalUsedQuota,                    QuotaUpdater quotaUpdater) {                        quotaUpdater.updateQuota(5 * 1024 * 1024);                    }            };        }       }}

<?xml version="1.0" encoding="utf-8"?><manifest>    <uses-permission android:name="android.permission.INTERNET" />     

    <uses-sdk/>    <application></application></manifest>