Android 中访问网页 webView

解决中文乱码问题：       

1.使用getBytes(“编码方式”);;来对汉字进行重编码，得到他的字节数组。

2.       再使用new String(Bytes[],”解码方式”);对字节数组进行相应的解码。

webKit应用

webKit分三个模块：javascriptCore,webCore和webKit.

WebView浏览网页：

 

几个重要的地方：

WebViewClient是专门辅助WebView处理各种通知，请求等事件的类。

webChromeClient是辅助WebView处理javascript的对话框，网站图标，网站title,加载进度。

package com.king.android.net;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.content.Context;
import android.content.DialogInterface;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.Window;
import android.view.View.OnClickListener;
import android.webkit.JsPromptResult;
import android.webkit.JsResult;
import android.webkit.URLUtil;
import android.webkit.WebChromeClient;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

import com.king.android.R;

/**

 * 描述：浏览网页
 * 作者：Andy.Liu
 * 时间： 2012-7-26  上午07:28:17
 **/
public class WebViewActivity extends Activity {
    
    Context mContext;
    Button btnConn;
    EditText etUrl;
    WebView wvShow;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        
        super.onCreate(savedInstanceState);
        mContext = WebViewActivity.this;
        setContentView(R.layout.webview_layout);
        
        btnConn = (Button) findViewById(R.id.btn_conn);
        etUrl = (EditText) findViewById(R.id.ed_show);
        wvShow = (WebView) findViewById(R.id.wv_view);
        
        btnConn.setOnClickListener(new OnClickListener(){

            @Override
            public void onClick(View v) {
                
                try{
                String url = etUrl.getText().toString();
                if(URLUtil.isNetworkUrl(url)){
                        wvShow.loadUrl(url);
                }else{
                    etUrl.setText("输入网址错误，请重新输入");
                }}catch(Exception e){
                }
                
            }});
        
        

  下面是主要知识点：

//设置javascript脚本        

WebSettings webSettings = wvShow.getSettings();
        webSettings.setJavaScriptEnabled(true);
        //设置可以访问文件
        webSettings.setAllowFileAccess(true);
        //设置支持缩放
        webSettings.setBuiltInZoomControls(true);
        
        /**
         * 设置WebViewClient
         * WebViewClient是专门辅助WebView处理各种通知，请求等事件的类。
         * */
        wvShow.setWebViewClient(webViewClient);
        /**
         * webChromeClient是辅助WebView处理javascript的对话框，网站图标，网站title,加载进度。
         * */
        wvShow.setWebChromeClient(webChromeClient);
        
        
    }
     
    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        if(KeyEvent.KEYCODE_BACK==keyCode){
            //返回前一个页面
            wvShow.goBack();
            return true;
        }
        
        return super.onKeyDown(keyCode, event);
    }
    
    private WebViewClient webViewClient = new WebViewClient(){
        public boolean shouldOverrideUrlLoading(WebView view,String url) {
            view.loadUrl(url);
            return true;
        }
        public void onPageFinished(WebView view,String url){
            super.onPageFinished(view, url);
        }
        
        public void onPageStarted(WebView view,String url,Bitmap favicon){
            super.onPageStarted(view, url,favicon);
        }
    };
    
    private WebChromeClient webChromeClient = new WebChromeClient(){
        //处理js中的alert
        public boolean onJsAlert(WebView view, String url, String message,final JsResult result) {
            Builder builder = new Builder(mContext);
            builder.setTitle("提示对话框");
            builder.setMessage(message);
            builder.setPositiveButton(android.R.string.ok, new AlertDialog.OnClickListener(){

                @Override
                public void onClick(DialogInterface dialog, int which) {
                    //点击确定按键之后，继续执行网页中的操作
                    result.confirm();
                }});
            builder.setCancelable(false);
            builder.create();
            builder.show();
            return true;
        };
        public boolean onJsConfirm(WebView view, String url, String message, final android.webkit.JsResult result) {
            Builder builder = new Builder(mContext);
            builder.setTitle("带选择的对话框");
            builder.setMessage(message);
            builder.setPositiveButton(android.R.string.ok, new AlertDialog.OnClickListener(){

                @Override
                public void onClick(DialogInterface dialog, int which) {
                    //点击确定按键之后，继续执行网页中的操作
                    result.confirm();
                }});
            builder.setNegativeButton(android.R.string.cancel, new AlertDialog.OnClickListener(){

                @Override
                public void onClick(DialogInterface dialog, int which) {
                    //点击取消
                    result.cancel();
                }});
            builder.setCancelable(false);
            builder.create();
            builder.show();
            return true;
        };
        @Override
        //处理javascript中的prompt
        //message为网页中对话框的提示内容
        //defaultValue在没有输入时，默认显示的内容
        public boolean onJsPrompt(WebView view, String url, String message,    String defaultValue, final JsPromptResult result) {
            //自定义一个带输入的对话框由TextView和EditText构成
            final LayoutInflater factory = LayoutInflater.from(mContext);
            final View dialogview = factory.inflate(R.layout.prom_dialog, null);
            ((TextView) dialogview.findViewById(R.id.TextView_PROM)).setText(message);
            ((EditText) dialogview.findViewById(R.id.EditText_PROM)).setText(defaultValue);
            
            Builder builder = new Builder(mContext);
            builder.setTitle("带输入的对话框");
            builder.setView(dialogview);
            builder.setPositiveButton(android.R.string.ok,
                    new AlertDialog.OnClickListener() {
                        public void onClick(DialogInterface dialog, int which) {
                            //点击确定之后，取得输入的值，传给网页处理
                            String value = ((EditText) dialogview.findViewById(R.id.EditText_PROM)).getText().toString();
                            result.confirm(value);
                        }
                    });
            builder.setNegativeButton(android.R.string.cancel,
                    new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int which) {
                            result.cancel();
                        }
                    });
            builder.setOnCancelListener(new DialogInterface.OnCancelListener() {
                        public void onCancel(DialogInterface dialog) {
                            result.cancel();
                        }
                    });
            builder.show();
            return true;
        };
        @Override
        //设置网页加载的进度条
        public void onProgressChanged(WebView view, int newProgress) 
        {
            WebViewActivity.this.getWindow().setFeatureInt(Window.FEATURE_PROGRESS, newProgress * 100);
            super.onProgressChanged(view, newProgress);
        }

        @Override
        //设置应用程序的标题title
        public void onReceivedTitle(WebView view, String title) 
        {
            WebViewActivity.this.setTitle(title);
            super.onReceivedTitle(view, title);
        }
    };

}

需要注意webView的几个地方