本文实例讲述了java swing中jlist选择事件监听器listselectionlistener用法。分享给大家供大家参考，具体如下：
当jlist中的元素被选中时，选择事件将被触发。对于jtable也是一样，你可以把它看做是多个并列的jlist。那么，如果程序需要对该事件做出响应，需要以下步骤：
(1)创建一个实现了 listselectionlistener的监听器；
(2)使用jlist或selectionmodel的addlistselectionlistener添加监听器；
(3)在监听器的valuechanged方法添加响应代码。
在响应代码中需要注意的是getvalueisadjusting值的判断。测试表明，每当我们进行选择时，valuechanged方法都会被激活多次，其中，在最后的鼠标操作中，getvalueisadjusting值为false，而在一系列中间操作中，该值均为true。比如说，用鼠标连续划过一串元素时，会有一系列getvalueisadjusting为true的valuechanged方法激活，且最后一次为false。而我们对选择事件的判定一般是以最后接触为准，因此这里对getvalueisadjusting值进行一个判断。
常用方法如下：
getleadselectionindex()返回当前选中的元素的index。
getminselectionindex()返回选中的多个元素中index的最小值，如果选择为空在返回-1。
getmaxselectionindex()原理同上。
isselectedindex(int index)判断指定index是否被选中。
clearselection()清除选中。
getselectedindex()返回被选中的所有元素中最小的index。
getselectedindices()返回一个整型数组，包含被选中的所有index。
getselectedvalue()返回被选中的，index最小的元素值。
getselectedvalues()返回一个object数组，包含被选中的所有元素对象。
getselectedvalueslist()返回一个objectlist，包含被选中的所有元素对象。
下面的demo来自于listselectiondemo.java
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/*
* copyright (c) 1995, 2008, oracle and/or its affiliates. all rights reserved.
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* modification, are permitted provided that the following conditions
* are met:
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* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
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* is" and any express or implied warranties, including, but not limited to,
* the implied warranties of merchantability and fitness for a particular
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* contributors be liable for any direct, indirect, incidental, special,
* exemplary, or consequential damages (including, but not limited to,
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* liability, whether in contract, strict liability, or tort (including
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*/
package awtdemo;
/*
* listselectiondemo.java requires no other files.
*/
import javax.swing.*;
import javax.swing.event.*;
import java.awt.*;
import java.awt.event.*;
@suppresswarnings("serial")
public class listselectiondemo extends jpanel {
jtextarea output;
@suppresswarnings("rawtypes")
jlist list;
jtable table;
string newline = "\n";
listselectionmodel listselectionmodel;
@suppresswarnings({ "unchecked", "rawtypes" })
public listselectiondemo() {
super(new borderlayout());
string[] listdata = { "one", "two", "three", "four",
"five", "six", "seven" };
@suppresswarnings("unused")
string[] columnnames = { "french", "spanish", "italian" };
list = new jlist(listdata);
listselectionmodel = list.getselectionmodel();
listselectionmodel.addlistselectionlistener(
new sharedlistselectionhandler());
jscrollpane listpane = new jscrollpane(list);
jpanel controlpane = new jpanel();
string[] modes = { "single_selection",
"single_interval_selection",
"multiple_interval_selection" };
final jcombobox combobox = new jcombobox(modes);
combobox.setselectedindex(2);
combobox.addactionlistener(new actionlistener() {
public void actionperformed(actionevent e) {
string newmode = (string)combobox.getselecteditem();
if (newmode.equals("single_selection")) {
listselectionmodel.setselectionmode(
listselectionmodel.single_selection);
} else if (newmode.equals("single_interval_selection")) {
listselectionmodel.setselectionmode(
listselectionmodel.single_interval_selection);
} else {
listselectionmodel.setselectionmode(
listselectionmodel.multiple_interval_selection);
}
output.append("----------"
+ "mode: " + newmode
+ "----------" + newline);
}
});
controlpane.add(new jlabel("selection mode:"));
controlpane.add(combobox);
//build output area.
output = new jtextarea(1, 10);
output.seteditable(false);
jscrollpane outputpane = new jscrollpane(output,
scrollpaneconstants.vertical_scrollbar_always,
scrollpaneconstants.horizontal_scrollbar_as_needed);
//do the layout.
jsplitpane splitpane = new jsplitpane(jsplitpane.vertical_split);
add(splitpane, borderlayout.center);
jpanel tophalf = new jpanel();
tophalf.setlayout(new boxlayout(tophalf, boxlayout.line_axis));
jpanel listcontainer = new jpanel(new gridlayout(1,1));
listcontainer.setborder(borderfactory.createtitledborder(
"list"));
listcontainer.add(listpane);
tophalf.setborder(borderfactory.createemptyborder(5,5,0,5));
tophalf.add(listcontainer);
//tophalf.add(tablecontainer);
tophalf.setminimumsize(new dimension(100, 50));
tophalf.setpreferredsize(new dimension(100, 110));
splitpane.add(tophalf);
jpanel bottomhalf = new jpanel(new borderlayout());
bottomhalf.add(controlpane, borderlayout.page_start);
bottomhalf.add(outputpane, borderlayout.center);
//xxx: next line needed if bottomhalf is a scroll pane:
//bottomhalf.setminimumsize(new dimension(400, 50));
bottomhalf.setpreferredsize(new dimension(450, 135));
splitpane.add(bottomhalf);
}
/**
* create the gui and show it. for thread safety,
* this method should be invoked from the
* event-dispatching thread.
*/
private static void createandshowgui() {
//create and set up the window.
jframe frame = new jframe("listselectiondemo - www.jb51.net");
frame.setdefaultcloseoperation(jframe.exit_on_close);
//create and set up the content pane.
listselectiondemo demo = new listselectiondemo();
demo.setopaque(true);
frame.setcontentpane(demo);
//display the window.
frame.pack();
frame.setvisible(true);
}
public static void main(string[] args) {
//schedule a job for the event-dispatching thread:
//creating and showing this application's gui.
javax.swing.swingutilities.invokelater(new runnable() {
public void run() {
createandshowgui();
}
});
}
class sharedlistselectionhandler implements listselectionlistener {
public void valuechanged(listselectionevent e) {
listselectionmodel lsm = (listselectionmodel)e.getsource();
//system.out.printf("leadselectionindex is %s%n",lsm.getleadselectionindex());
output.append("leadselectionindex is " + lsm.getleadselectionindex() + "\n");
int firstindex = e.getfirstindex();
int lastindex = e.getlastindex();
boolean isadjusting = e.getvalueisadjusting();
output.append("event for indexes "
+ firstindex + " - " + lastindex
+ "; isadjusting is " + isadjusting
+ "; selected indexes:");
if (lsm.isselectionempty()) {
output.append(" <none>");
} else {
// find out which indexes are selected.
int minindex = lsm.getminselectionindex();
int maxindex = lsm.getmaxselectionindex();
for (int i = minindex; i <= maxindex; i++) {
if (lsm.isselectedindex(i)) {
output.append(" " + i);
}
}
}
output.append(newline);
output.setcaretposition(output.getdocument().getlength());
}
}
}
运行效果：
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