onPageFinished() 从未调用过（webview）！

我想在网络视图完全加载时显示一个祝酒词。但吐司从未出现，我不知道为什么......这是我的代码：

public class WebViewSignUp extends Activity{

    WebView mWebView;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.webviewsignup);

        mWebView = (WebView) findViewById(R.id.webview);
        mWebView.getSettings().setJavaScriptEnabled(true);

        ((TextView)findViewById(R.id.home)).setOnClickListener(new OnClickListener(){
            public void onClick(View v) {
                finish();
            } 
         });

    mWebView.setWebViewClient(new WebViewClient() {
        @Override  
        public void onPageFinished(WebView view, String url) {
             super.onPageFinished(mWebView, url);

            Toast.makeText(getApplicationContext(), "Done!", Toast.LENGTH_SHORT).show();
        }  
    });
    mWebView.loadUrl("http://pabebbe.com/m/register");

    mWebView.setWebViewClient(new WebViewClient() {
       public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
         Toast.makeText(getApplicationContext(), "Oh no! " + description, Toast.LENGTH_SHORT).show();
       }
       });
    }
}

第二次致电setWebViewClient()正在覆盖第一个。

只创建一个实例WebViewClient在同一个类中使用两个重写，并调用setWebViewClient只有一次。然后加载Webview：

mWebView.setWebViewClient(new WebViewClient() {
    @Override  
    public void onPageFinished(WebView view, String url) {
        super.onPageFinished(mWebView, url);
        Toast.makeText(getApplicationContext(), "Done!", Toast.LENGTH_SHORT).show();
    }  

    @Override
    public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
        Toast.makeText(getApplicationContext(), "Oh no! " + description, Toast.LENGTH_SHORT).show();
    }
});
mWebView.loadUrl("http://pabebbe.com/m/register");