我正在尝试使用 Applet 中的 setter 方法将选定的值从 HTML 下拉列表传递到 Applet 方法。但是每次调用 Javascript 时，它都会显示“对象不支持此属性或方法”作为异常。
我的 javascript 代码:
function showSelected(value){
alert("the value given from"+value);
var diseasename=value;
alert(diseasename);
document.decisiontreeapplet.setDieasename(diseasename);
alert("i am after value set ");
}
我的小程序代码:
package com.vaannila.utility;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import prefuse.util.ui.JPrefuseApplet;
public class dynamicTreeApplet extends JPrefuseApplet {
private static final long serialVersionUID = 1L;
public static int i = 1;
public String dieasenameencode;
//System.out.println("asjdjkhcd"+dieasenameencode);
public void init() {
System.out.println("asjdjkhcd"+dieasenameencode);
System.out.println("the value of i is " + i);
URL url = null;
//String ashu=this.getParameter("dieasenmae");
//System.out.println("the value of the dieases is "+ashu);
//Here dieasesname is important to make the page refresh happen
//String dencode = dieasenameencode.trim();
try {
//String dieasename = URLEncoder.encode(dencode, "UTF-8");
// i want this piece of the code to be called
url = new URL("http://localhost:8080/docRuleToolProtocol/appletRefreshAction.do?dieasename="+dieasenameencode);
URLConnection con = url.openConnection();
con.setDoOutput(true);
con.setDoInput(true);
con.setUseCaches(false);
InputStream ois = con.getInputStream();
this.setContentPane(dynamicView.demo(ois, "name"));
ois.close();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (FileNotFoundException f) {
f.printStackTrace();
} catch (IOException io) {
io.printStackTrace();
}
++i;
}
public void setDieasename(String message){
System.out.println("atleast i am here and call is made ");
this.dieasenameencode=message;
System.out.println("the final value of the dieasenmae"+dieasenameencode);
}
}
我的小程序部署代码:
<applet id="decisiontreeapplet" code="com.vaannila.utility.dynamicTreeApplet.class" archive="./appletjars/dynamictree.jar, ./appletjars/prefuse.jar" width ="1000" height="500" >
</applet>
最佳答案
改变..
document.decisiontreeapplet
..到..
document.getElementById('decisiontreeapplet')
..它很可能会起作用。
例如
HTML
<html>
<body>
<script type='text/javascript'>
function callApplet() {
msg = document.getElementById('input').value;
applet = document.getElementById('output');
applet.setMessage(msg);
}
</script>
<input id='input' type='text' size=20 onchange='callApplet()'>
<br>
<applet
id='output'
code='CallApplet'
width=120
height=20>
</applet>
</body>
</html>
Java
import javax.swing.*;
public class CallApplet extends JApplet {
JTextField output;
public void init() {
output = new JTextField(20);
add(output);
validate();
}
public void setMessage(String message) {
output.setText(message);
}
}
下次还请考虑发布一个简短的完整示例。请注意，上面显示的两个来源中的行数比您的例如短。小程序，我花了更长的时间来准备源代码，以便检查我的答案。
关于Javascript 到 Java Applet 通信，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/7278626/