<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
android:layout_width="fill_parent" 
android:layout_height="fill_parent" 
android:orientation="vertical" > 
<LinearLayout 
android:orientation="horizontal" 
android:layout_width="fill_parent" 
android:layout_height="wrap_content" > 
<EditText 
android:id="@+id/et_url" 
android:layout_width="320dp" 
android:layout_height="wrap_content" /> 
<Button 
android:id="@+id/btn_login" 
android:layout_height="wrap_content" 
android:layout_width="wrap_content" 
android:text="登錄" 
/> 
</LinearLayout> 
<WebView 
android:layout_weight="2" 
android:id="@+id/webView" 
android:layout_width="fill_parent" 
android:layout_height="fill_parent" /> 
<LinearLayout 
android:layout_weight="7.5" 
android:layout_width="fill_parent" 
android:layout_height="fill_parent" 
android:orientation="horizontal" 
android:background="#000000" 
> 
<Button 
android:id="@+id/btn_back" 
android:layout_weight="1" 
android:layout_height="wrap_content" 
android:layout_width="wrap_content" 
android:text="←" 
/> 
<Button 
android:id="@+id/btn_menu" 
android:layout_weight="1" 
android:layout_height="wrap_content" 
android:layout_width="wrap_content" 
android:text="主頁" 
/> 
<Button 
android:id="@+id/btn_forward" 
android:layout_weight="1" 
android:layout_height="wrap_content" 
android:layout_width="wrap_content" 
android:text="→" 
/> 
<Button 
android:id="@+id/btn_exit" 
android:layout_weight="1" 
android:layout_height="wrap_content" 
android:layout_width="wrap_content" 
android:text="exit" 
/> 
</LinearLayout> 
</LinearLayout> 

package com.example.webview; 
import android.os.Bundle; 
import android.app.Activity; 
import android.view.KeyEvent; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.view.Window; 
import android.webkit.WebChromeClient; 
import android.webkit.WebSettings; 
import android.webkit.WebView; 
import android.webkit.WebViewClient; 
import android.widget.Button; 
import android.widget.EditText; 
public class MainActivity extends Activity implements OnClickListener { 
private String url = null; 
private WebView webView; 
private EditText et_url; 
private Button btn_login; 
private Button btn_back; 
private Button btn_exit; 
private Button btn_forward; 
private Button btn_menu; 
@Override 
protected void onCreate(Bundle savedInstanceState) { 
super.onCreate(savedInstanceState); 
// 窗口進度條 
requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS); 
setContentView(R.layout.activity_main); 
setProgressBarIndeterminate(true); 
webView = (WebView) findViewById(R.id.webView); 
et_url = (EditText) findViewById(R.id.et_url); 
btn_login = (Button) findViewById(R.id.btn_login); 
btn_back = (Button) findViewById(R.id.btn_back); 
btn_exit = (Button) findViewById(R.id.btn_exit); 
btn_forward = (Button) findViewById(R.id.btn_forward); 
btn_menu = (Button) findViewById(R.id.btn_menu); 
// 對五個按鈕添加點擊監(jiān)聽事件 
btn_login.setOnClickListener(this); 
btn_back.setOnClickListener(this); 
btn_exit.setOnClickListener(this); 
btn_forward.setOnClickListener(this); 
btn_menu.setOnClickListener(this); 
} 
// btn_login的觸發(fā)事件 點擊后 webView開始讀取url 
protected void startReadUrl(String url) { 
// TODO Auto-generated method stub 
// webView加載web資源 
webView.loadUrl(url); 
// 覆蓋webView默認通過系統(tǒng)或者第三方瀏覽器打開網(wǎng)頁的行為 
// 如果為false調(diào)用系統(tǒng)或者第三方瀏覽器打開網(wǎng)頁的行為 
webView.setWebViewClient(new WebViewClient() { 
@Override 
public boolean shouldOverrideUrlLoading(WebView view, String url) { 
// TODO Auto-generated method stub 
// webView加載web資源 
view.loadUrl(url); 
return true; 
} 
}); 
// 啟用支持javascript 
WebSettings settings = webView.getSettings(); 
settings.setJavaScriptEnabled(true); 
// web加載頁面優(yōu)先使用緩存加載 
settings.setCacheMode(WebSettings.LOAD_CACHE_ELSE_NETWORK); 
// 當打開頁面時 顯示進度條 頁面打開完全時 隱藏進度條 
webView.setWebChromeClient(new WebChromeClient() { 
@Override 
public void onProgressChanged(WebView view, int newProgress) { 
// TODO Auto-generated method stub 
setTitle("本頁面已加載" + newProgress + "%"); 
if (newProgress == 100) { 
closeProgressBar(); 
} else { 
openProgressBar(newProgress); 
} 
super.onProgressChanged(view, newProgress); 
} 
}); 
} 
// 打開進度條 
protected void openProgressBar(int x) { 
// TODO Auto-generated method stub 
setProgressBarIndeterminateVisibility(true); 
setProgress(x); 
} 
// 關(guān)閉進度條 
protected void closeProgressBar() { 
// TODO Auto-generated method stub 
setProgressBarIndeterminateVisibility(false); 
} 
// 改寫物理按鍵 返回鍵的邏輯 
@Override 
public boolean onKeyDown(int keyCode, KeyEvent event) { 
// TODO Auto-generated method stub 
if (keyCode == KeyEvent.KEYCODE_BACK) { 
if (webView.canGoBack()) { 
// 返回上一頁面 
webView.goBack(); 
return true; 
} else { 
// 退出程序 
finish(); 
} 
} 
return super.onKeyDown(keyCode, event); 
} 
// 對按鈕事件的處理 
@Override 
public void onClick(View v) { 
// TODO Auto-generated method stub 
switch (v.getId()) { 
case R.id.btn_login: 
url = "http://" + et_url.getText().toString(); 
url = url.replace(" ", ""); 
startReadUrl(url); 
break; 
case R.id.btn_back: 
if (webView.canGoBack()) { 
webView.goBack(); 
} else { 
finish(); 
} 
break; 
case R.id.btn_forward: 
if (webView.canGoForward()) { 
webView.goForward(); 
} 
break; 
case R.id.btn_exit: 
finish(); 
break; 
case R.id.btn_menu: 
startReadUrl("http://www.baidu.com"); 
break; 
} 
} 
}

<uses-permission android:name="android.permission.INTERNET"/>