android WebView HTML5 access database problem_问答_开发者

i am work at an app which Embed an WebView and display a HTML5 page .

when open the html page in android chrome Browser.the database was create normal.

but when i run this app , the database can not create . it seem that html page can not create the database on WebView.

anybody know why?

here is my Activity code:

 public class efan_NewsReader extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);        
    WebView myWebView=(WebView)findViewById(R.id.my_webview);
    myWebView.setWebViewClient(new WebViewClient());
    WebSettings settings = myWebView.getSettings();  
    settings.setJavaScriptEnabled(true);
    settings.setDomStorageEnabled(true);
    settings.setDatabaseEnabled(true);
    settings.setAppCacheEnabled(false);        

    myWebView.loadUrl("http://10.10.35.47:8080/html5test/test.htm");

}}

here is my HTML5 page source code：

    <html manifest="mymanife开发者_StackOverflow社区st.manifest">
    <head>
<meta http-equiv="Content-Type" content="text/html; content="no-cache" charset=utf-8" />
<script type="text/javascript" src="js/jquery-1.6.1.min.js"></script>

<script>
$(document).ready(function(){       

    databaseTest();
});

function databaseTest(){


    //open database
     var db = openDatabase('mydb', '1.0', 'Test DB', 2 * 1024 * 1024);  

      db.transaction(function (tx) {            
      tx.executeSql('CREATE TABLE IF NOT EXISTS testHtml (id unique, contentText)');
      tx.executeSql('INSERT INTO testHtml (contentText) VALUES ("insert data test!")');  
       });  

     db.transaction(function(tx){           
     tx.executeSql('SELECT * FROM testHtml',[],function(tx,result){
            var len=result.rows.length;
            var msg = "<p>Found rows: " + len + "</p>";  
             $("#testinfo").append(msg);
        },null);
     });    


}

</script>


</head>
<body>
    <div>here is test info:</div>
    <div id="testinfo"></div>
</body>

Try :

settings.setDatabaseEnabled(true);
String dbPath = this.getApplicationContext().getDir("database", Context.MODE_PRIVATE).getPath();
settings.setDatabasePath(dbPath);

And in WebChromeClient :

myWebView.setWebChromeClient(new WebChromeClient()
{
    @Override
    public void onExceededDatabaseQuota(String url, String databaseIdentifier, long currentQuota, long estimatedSize, long totalUsedQuota, WebStorage.QuotaUpdater quotaUpdater)
    {
        quotaUpdater.updateQuota(estimatedSize * 2);
    }
}

It should be OK ;)

new WebChromeClient() was throwing a constructor error so I did it this way. private WebView webView;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.test_web);

    webView = (WebView) findViewById(R.id.webView1);


    webView.getSettings().setJavaScriptEnabled(true);
    webView.getSettings().setDatabaseEnabled(true);
    webView.getSettings().setDomStorageEnabled(true);
    //String sDataPath = "/data/data/" + webView.getContext().getPackageName() + "/databases/";
    String sDataPath = this.getApplicationContext().getDir("database", Context.MODE_PRIVATE).getPath();
    webView.getSettings().setDatabasePath(sDataPath);
    webView.getSettings().setDatabaseEnabled(true);
    webView.getSettings().setSavePassword(true);
    webView.getSettings().setAllowContentAccess(true);
    webView.getSettings().setAllowFileAccess(true);

    webView.setWebViewClient(new Callback());
    webView.setWebChromeClient(new webChromeClient());
    webView.loadUrl("http://www.yahoo.com");        
}

 private class Callback extends WebViewClient{  

        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            return (false);
        }

 }
 private class webChromeClient extends WebChromeClient
 {
     @Override
        public void onExceededDatabaseQuota(String url, String databaseIdentifier, long currentQuota, long estimatedSize, long totalUsedQuota, WebStorage.QuotaUpdater quotaUpdater) { 
         quotaUpdater.updateQuota(5 * 1024 * 1024); 
     }       
 }

It's likely that the default quota is 0, so onExceededDatabaseQuota is a must