Android 中可以通过webview来实现和js的交互,在程序中调用js代码,只需要将webview控件的支持js的属性设置为true

Android(Java)与JavaScript(HTML)交互有四种情况:

1) Android(Java)调用HTML中js代码

2) Android(Java)调用HTML中js代码(带参数)

3) HTML中js调用Android(Java)代码

4) HTML中js调用Android(Java)代码(带参数)

下面示例总结这四种情况,直接上干货:


1) Android(Java)

	private void showWebView(){		// webView与js交互代码
		try {
			mWebView = new WebView(this);
			setContentView(mWebView);
			
			mWebView.requestFocus();
			
			mWebView.setWebChromeClient(new WebChromeClient(){
				@Override
				public void onProgressChanged(WebView view, int progress){
					JSAndroidActivity.this.setTitle("Loading...");
					JSAndroidActivity.this.setProgress(progress);
					
					if(progress >= 80) {
						JSAndroidActivity.this.setTitle("JsAndroid Test");
					}
				}
			});
			
			mWebView.setOnKeyListener(new View.OnKeyListener() {		// webview can go back
				@Override
				public boolean onKey(View v, int keyCode, KeyEvent event) {
					if(keyCode == KeyEvent.KEYCODE_BACK && mWebView.canGoBack()) {
						mWebView.goBack();
						return true;
					}
					return false;
				}
			});
			
			WebSettings webSettings = mWebView.getSettings();
			webSettings.setJavaScriptEnabled(true);
			webSettings.setDefaultTextEncodingName("utf-8");

			mWebView.addJavascriptInterface(getHtmlObject(), "jsObj");
			mWebView.loadUrl("http://192.168.1.121:8080/jsandroid/index.html");
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	
	private Object getHtmlObject(){
		Object insertObj = new Object(){
			public String HtmlcallJava(){
				return "Html call Java";
			}
			
			public String HtmlcallJava2(final String param){
				return "Html call Java : " + param;
			}
			
			public void JavacallHtml(){
				runOnUiThread(new Runnable() {
					@Override
					public void run() {
						mWebView.loadUrl("javascript: showFromHtml()");
						Toast.makeText(JSAndroidActivity.this, "clickBtn", Toast.LENGTH_SHORT).show();
					}
				});
			}
			
			public void JavacallHtml2(){
				runOnUiThread(new Runnable() {
					@Override
					public void run() {
						mWebView.loadUrl("javascript: showFromHtml2('IT-homer blog')");
						Toast.makeText(JSAndroidActivity.this, "clickBtn2", Toast.LENGTH_SHORT).show();
					}
				});
			}
		};
		
		return insertObj;
	}


2) js(HTML)

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<!-- saved from url=(0032)http://localhost:8080/jsandroid/ -->
<html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

<meta http-equiv="Expires" content="0">
<meta http-equiv="Pragma" content="no-cache">
<meta http-equiv="Cache-Control" content="no-store,no-cache"> 
<meta name="Handheldfriendly" content="true">
<meta name="viewport" content="width=100%; initial-scale=1.0; user-scalable=yes">
<meta name="robots" content="all">
<meta name="keywords" contect="doodle, mobile, doodlemobile, game, games">
<meta name="description" content="Make People's Mobile Life More Connected Through Games.">

<title>jsandroid_test</title>

<script type="text/javascript" language="javascript"> 
	
	function showHtmlcallJava(){
		var str = window.jsObj.HtmlcallJava();
		alert(str);
	}
	
	function showHtmlcallJava2(){
		var str = window.jsObj.HtmlcallJava2("IT-homer blog");
		alert(str);
	}
	
	function showFromHtml(){
		document.getElementById("id_input").value = "Java call Html";
	}
	
	function showFromHtml2( param ){
		document.getElementById("id_input2").value = "Java call Html : " + param; 
	}
</script>
</head>


<body>

hello IT-homer

<br>
<br>
<br>

<input type="button" value="HtmlcallJava" onclick="showHtmlcallJava()" />
<br>
<input type="button" value="HtmlcallJava2" onclick="showHtmlcallJava2()" />

<br>
<br>
<br>
<br>

<input id="id_input" style="width: 90%" type="text" value="null" />
<br>
<input type="button" value="JavacallHtml" onclick="window.jsObj.JavacallHtml()" />

<br>
<br>
<br>

<input id="id_input2" style="width: 90%" type="text" value="null" />
<br>
<input type="button" value="JavacallHtml2" onclick="window.jsObj.JavacallHtml2()" />

</body>
</html>


3) 运行结果:



4) 代码解析:

(1) 允许Android执行js脚本设置

Android(Java)与js(HTML)交互的接口函数是: mWebView.addJavascriptInterface(getHtmlObject(), "jsObj");     // jsObj 为桥连对象

Android容许执行js脚本需要设置: webSettings.setJavaScriptEnabled(true);

(2) js(HTML)访问Android(Java)代码

js(HTML)访问Android(Java)端代码是通过jsObj对象实现的,调用jsObj对象中的函数,如: window.jsObj.HtmlcallJava()

(3) Android(Java)访问js(HTML)代码

Android(Java)访问js(HTML)端代码是通过loadUrl函数实现的,访问格式如:mWebView.loadUrl("javascript: showFromHtml()");


说明:

1) Android访问url网址,需在AndroidManifest.xml文件,配置容许访问网络的权限:


<uses-permission android:name="


android.permission.INTERNET


" />

2) Android(Java)调用js(HTML)时,使用的mWebView.loadUrl("javascript: showFromHtml()");函数需在UI线程运行,因为mWebView为UI控件

			public void JavacallHtml(){
				runOnUiThread(new Runnable() {
					@Override
					public void run() {
						mWebView.loadUrl("javascript: showFromHtml()");
						Toast.makeText(JSAndroidActivity.this, "clickBtn", Toast.LENGTH_SHORT).show();
					}
				});
			}


源码下载



参考推荐:


Android中webview和js之间的交互


Android中 Js 扩展及交互