package com.lxq.webview01;

import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnClickListener;
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 {

  private EditText et_url;
  private Button btn_request;
  private WebView wv;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    initView();
    initSetting();
    initEvent();

  }

  private void initSetting() {
    //webview设置属性
    WebSettings ws=wv.getSettings();
    ws.setBuiltInZoomControls(true);
    ws.setDefaultZoom(WebSettings.ZoomDensity.FAR);
    ws.setJavaScriptEnabled(true);
    ws.setSupportZoom(true);
    //点击链接继续在当前browser中响应，而不是新开Android的系统browser中响应该链接，必须覆盖 webview的WebViewClient对象
    wv.setWebViewClient(new WebViewClient(){    
      public boolean shouldOverrideUrlLoading(WebView view, String url) {    
        view.loadUrl(url);    
        return true;    
      }    
    });  

  }

  //初始化控件
  private void initView() {
    et_url =(EditText)findViewById(R.id.et_url);    
    btn_request = (Button)findViewById(R.id.btn_request);    
    wv= (WebView)findViewById(R.id.wv);   
  }
  //按键监听
  public boolean onKeyDown(int keyCode, KeyEvent event) {    
    if ((keyCode == KeyEvent.KEYCODE_BACK) && wv.canGoBack()) {    
      wv.goBack();    
      return true;    
    }    
    return super.onKeyDown(keyCode, event);    
  } 
  //初始化事件
  private void initEvent() {

    btn_request.setOnClickListener(new OnClickListener() {

      @Override
      public void onClick(View v) {
        String url=et_url.getText().toString().trim();
        wv.loadUrl(url);
      }
    });
  }

}

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
  package="com.lxq.webview01"
  android:versionCode="1"
  android:versionName="1.0" >

  <uses-sdk
    android:minSdkVersion="8"
    android:targetSdkVersion="17" />
  <uses-permission android:name="android.permission.INTERNET"/>

  <application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
    <activity
      android:name="com.lxq.webview01.MainActivity"
      android:label="@string/app_name" >
      <intent-filter>
        <action android:name="android.intent.action.MAIN" />

        <category android:name="android.intent.category.LAUNCHER" />
      </intent-filter>
    </activity>
  </
app````
ication>

</manifest>