135、JS和Android交互范例
很简单的直接上代码
<uses-permission android:name="android.permission.INTERNET" />
assets/web.html
<html>
<head>
<meta http-equiv="Content-Type" content="text/html;charset=gb2312">
<script type="text/javascript">
function javacalljs(){
document.getElementById("content").innerHTML =
"<br\>JAVA调用了JS的函数";
}
function javacalljswith(arg){
document.getElementById("content").innerHTML =
("<br\>"+arg);
}
</script>
</head>
<body>
HTML 内容显示 <br/>
<h1>
<div id="content">内容显示</div>
</h1>
<br/>
<input type="button" value="点击调用java代码" onclick="window.android.startFunction()"/>
<br/>
<input type="button" value="点击调用java代码并传递参数"
onclick="window.android.startFunction('http://blog.csdn.net/Leejizhou')"/>
</body>
</html>
package com.leejz.jsdemo;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.webkit.JavascriptInterface;
import android.webkit.WebView;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
private WebView contentWebView = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
contentWebView = (WebView) findViewById(R.id.webview);
// 启用javascript
contentWebView.getSettings().setJavaScriptEnabled(true);
// 从assets目录下面的加载html
contentWebView.loadUrl("file:///android_asset/web.html");
contentWebView.addJavascriptInterface(MainActivity.this, "android");
//无参调用Js点击
findViewById(R.id.button).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// 无参数调用 WebView中显示 JAVA调用了JS的函数
contentWebView.loadUrl("javascript:javacalljs()");
}
});
//有参调用Js点击
findViewById(R.id.button2).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// 传递参数调用 WebView中显示 www.baidu.com
contentWebView.loadUrl("javascript:javacalljswith("
+ "'www.baidu.com'" + ")");
}
});
}
//由于安全原因 需要加 @JavascriptInterface
@JavascriptInterface
public void startFunction() {
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(MainActivity.this, "吐司", Toast.LENGTH_SHORT).show();
}
});
}
@JavascriptInterface
public void startFunction(final String text) {
runOnUiThread(new Runnable() {
@Override
public void run() {
new AlertDialog.Builder(MainActivity.this).setMessage(text).show();
}
});
}
}
