WebView主要运用! _Web前端

WebView重要运用!!

WebView使得Java和JavaScript可以互相的调用.
请看例子:

WebviewActivity.java

package com.cn;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.webkit.WebSettings;
import android.webkit.WebView;

public class WebviewActivity extends Activity {
    /** Called when the activity is first created. */
	private WebView mWebView;  
    private Handler mHandler = new Handler(); 
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        mWebView = (WebView) findViewById(R.id.webview);  
        WebSettings webSettings = mWebView.getSettings();  
        webSettings.setJavaScriptEnabled(true);  
        mWebView.addJavascriptInterface(new Object() {  
            public void clickOnAndroid() {  
                mHandler.post(new Runnable() {  
                    public void run() {  
                    	//Java调用Javascript方法
                        mWebView.loadUrl("javascript:wave()");  
                    }  
                });  
            }  
        }, "demo");  
        //访问本地程序assets文件夹中的demo.html页面
        mWebView.loadUrl("file:///android_asset/demo.html");
        /**
         * 如果访问网站. 如http://rayln.iteye.com. 需要在AndroidManifest.xml中加入网络访问权限
         * <uses-permission android:name="android.permission.INTERNET"></uses-permission>
         * 例如:
         * mWebView.loadUrl("http://rayln.iteye.com");
        **/
    }
}

/assets/demo.html

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<script>
	function runDemo(){
		//Javascript调用Java方法
		window.demo.clickOnAndroid();
	}
	function wave() {  
        document.getElementById("change").innerText="Java中整用JS写入";  
    }
</script>
<body>
	<input value="点击我!!" onclick="runDemo()" type="button"/>
	<div id="change"></div>
</body>
</html>

PS:如果访问网站. 如http://rayln.iteye.com. 需要在AndroidManifest.xml中加入网络访问权限..
<uses-permission android:name="android.permission.INTERNET"></uses-permission>