Android 网页加载完成ProgressDialog运用

package gongzibai.co.cc;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.ProgressDialog;
import android.content.DialogInterface;
import android.os.Bundle;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.Toast;

public class WebView2Activity extends
Activity {

private ProgressDialog progressBar;
WebView webview;
AlertDialog alertDialog;

/** Called when the activity is first created. */
@Override
public void onCreate(
Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
webview = (WebView) findViewById(R.id.webview);
progressBar = ProgressDialog
.show(WebView2Activity.this,
null,
"正在进入网页，请稍后

…");
webview.getSettings()
.setJavaScriptEnabled(
true);

webview.loadUrl("http://www.qq.com");

AlertDialog alertDialog = new AlertDialog.Builder(
this).create();

// 设置视图客户端
webview.setWebViewClient(new MyWebViewClient());

}

class MyWebViewClient extends
WebViewClient {

@Override
public boolean shouldOverrideUrlLoading(
WebView view, String url) {
// TODO Auto-generated method stub

view.loadUrl(url);
return super
.shouldOverrideUrlLoading(
view, url);
}

public void onPageFinished(
WebView view, String url) {
// TODO Auto-generated method stub
if (progressBar.isShowing()) {
progressBar.dismiss();

}
}
}
}