webview加载页面及前进、后退、刷新操作

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.webkit.WebChromeClient;
import android.webkit.WebView;
import android.webkit.WebViewClient;

public class MainActivity extends Activity {

private WebView wv2;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
wv2 = (WebView) findViewById(R.id.container);
wv2.getSettings().setBuiltInZoomControls(true);
wv2.getSettings().setJavaScriptEnabled(true);
wv2.setWebViewClient(new WebViewClient());
wv2.setWebChromeClient(new WebChromeClient() {
public void onProgressChanged(WebView view, int newProgress) {
setProgress(newProgress * 100);
if (newProgress == 100) {
//隐藏进度提示
}
}
});
wv2.loadUrl("http://www.baidu.com");
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
// TODO Auto-generated method stub
switch (item.getItemId()) {
case R.id.backward:
wv2.goBack();
break;
case R.id.forward:
wv2.goForward();
break;
case R.id.refresh:
wv2.reload();
break;

default:
break;
}
return true;
}

}