如何在Android中显示webView和隐藏其他元素

我是Android开发的新手，会介绍一些我使用Eclipse开发Android代码的教程。在这里，我尝试在单击按钮后用一些URL加载WebView，然后隐藏该按钮。

我正在使用线性布局。为此，我使用了以下代码来使其正常工作，但它并未加载WebView。

public class MainActivity extends ActionBarActivity {

    EditText edit;
    TextView text;
    WebView webView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        edit = (EditText) findViewById(R.id.editText);
        text = (TextView) findViewById(R.id.textView3);
        webView = (WebView) findViewById(R.id.webView1);

        Button b = (Button)findViewById(R.id.button_show);

        b.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                String name = edit.getText().toString();
                text.append(name);
                webView.loadUrl("http://www.google.com");
                System.out.println("Loaded Successfully--");
            }
        });
    }

消息“已成功加载-”在控制台中打印，但是WebView不可用。

我也尝试了以下代码，

EditText edit;
TextView text;
WebView webView;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    edit = (EditText) findViewById(R.id.editText);
    text = (TextView) findViewById(R.id.textView3);
    webView = (WebView) findViewById(R.id.webView1);

    Button b = (Button)findViewById(R.id.button_show);

    b.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            String name = edit.getText().toString();
            text.append(name);
            webView.setWebViewClient(new WebViewClient() {
                @Override
                public boolean shouldOverrideUrlLoading(WebView view,
                        String url) {
                    webView.loadUrl("http://www.google.com");
                    System.out.println("Loaded Successfully--");
                    return true;
                }
            });
        }
    });
}

这次不打印“成功加载-”。我在这里想念什么？

编辑

我的XMl文件（activity_main.xml）

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="fill"
    tools:context="com.example.asdf.MainActivity" >

    <WebView
        android:id="@+id/webView1"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_alignParentLeft="true"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true"
        android:scaleType="fitXY"
        android:src="@drawable/back" />

   <EditText
       android:id="@+id/editText"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:layout_alignBottom="@+id/imageView1"
       android:layout_alignLeft="@+id/imageView1"
       android:layout_marginBottom="24dp"
       android:ems="10"
       android:hint="@string/edit_hint"
       android:textColor="#ffffff"
       android:textSize="20dip" >

       <requestFocus />
   </EditText>

   <Button
       android:id="@+id/button_show"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:layout_alignBottom="@+id/editText"
       android:layout_alignRight="@+id/imageView1"
       android:text="@string/button_title" />

   <TextView
       android:id="@+id/textView3"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:layout_alignBottom="@+id/imageView1"
       android:layout_alignLeft="@+id/imageView1"
       android:layout_alignRight="@+id/imageView1"
       android:layout_below="@+id/button_show"
       android:text="@string/edit_hint"
       android:textColor="#ffffff"
       android:textSize="20dip" />

   <TextView
       android:id="@+id/textView2"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:layout_alignParentLeft="true"
       android:layout_centerVertical="true"
       android:gravity="center"
       android:text="As we know the relevant data has been wide-spreaded across various sites under many intentions, factualnote is a type of social software tool in which factual data are brought forward or narrow down to the web users."
       android:textColor="#ffffff"
       android:textSize="20dip"
       android:textStyle="bold" />

   <TextView
       android:id="@+id/textView1"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:layout_above="@+id/textView2"
       android:layout_alignParentLeft="true"
       android:layout_marginBottom="22dp"
       android:gravity="center"
       android:text="Factualnote is an web annotation application, which helps the users to mark the specific text, element, page, video, etc in a web page and share it to like-minded people."
       android:textColor="#ffffff"
       android:textSize="20dip"
       android:textStyle="bold" />

</RelativeLayout>