Java实现Map集合二级联动示例.docx
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Java实现Map集合二级联动示例.docx
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Java实现Map集合二级联动示例
Java实现Map集合二级联动示例
Java实现Map集合二级联动示例,需要的朋友可以参考下
Map集合可以保存键值映射关系,这非常适合本实例所需要的数据结构,所有省份信息可以保存为Map集合的键,而每个键可以保存对应的城市信息,本实例就是利用Map集合实现了省市级联选择框,当选择省份信息时,将改变城市下拉选择框对应的内容。
思路分析:
1.创建全国(省,直辖市,自治区)映射集合,即LinkedHashMap对象,使用Map接口的put()方法向集合中添加指定的省与城市的映射关系,其中值为String型一维数组。
代码如下:
CityMap.java
复制代码代码如下:
importjava.util.LinkedHashMap;
importjava.util.Map;
publicclassCityMap{
/**
*全国(省,直辖市,自治区)映射集合
*/
publicstaticMap
static{
model.put("北京",newString[]{"北京"});
model.put("上海",newString[]{"上海"});
model.put("天津",newString[]{"天津"});
model.put("重庆",newString[]{"重庆"});
model.put("黑龙江",newString[]{"哈尔滨","齐齐哈尔","牡丹江","大庆","伊春","双鸭山","鹤岗","鸡西","佳木斯","七台河","黑河","绥化","大兴安岭"});
model.put("吉林",newString[]{"长春","延边","吉林","白山","白城","四平","松原","辽源","大安","通化"});
model.put("辽宁",newString[]{"沈阳","大连","葫芦岛","旅顺","本溪","抚顺","铁岭","辽阳","营口","阜新","朝阳","锦州","丹东","鞍山"});
model.put("内蒙古",newString[]{"呼和浩特","呼伦贝尔","锡林浩特","包头","赤峰","海拉尔","乌海","鄂尔多斯","通辽"});
model.put("河北",newString[]{"石家庄","唐山","张家口","廊坊","邢台","邯郸","沧州","衡水","承德","保定","秦皇岛"});
model.put("河南",newString[]{"郑州","开封","洛阳","平顶山","焦作","鹤壁","新乡","安阳","濮阳","许昌","漯河","三门峡","南阳","商丘","信阳","周口","驻马店"});
model.put("山东",newString[]{"济南","青岛","淄博","威海","曲阜","临沂","烟台","枣庄","聊城","济宁","菏泽","泰安","日照","东营","德州","滨州","莱芜","潍坊"});
model.put("山西",newString[]{"太原","阳泉","晋城","晋中","临汾","运城","长治","朔州","忻州","大同","吕梁"});
model.put("江苏",newString[]{"南京","苏州","昆山","南通","太仓","吴县","徐州","宜兴","镇江","淮安","常熟","盐城","泰州","无锡","连云港","扬州","常州","宿迁"});
model.put("安徽",newString[]{"合肥","巢湖","蚌埠","安庆","六安","滁州","马鞍山","阜阳","宣城","铜陵","淮北","芜湖","毫州","宿州","淮南","池州"});
model.put("陕西",newString[]{"西安","韩城","安康","汉中","宝鸡","咸阳","榆林","渭南","商洛","铜川","延安"});
model.put("宁夏",newString[]{"银川","固原","中卫","石嘴山","吴忠"});
model.put("甘肃",newString[]{"兰州","白银","庆阳","酒泉","天水","武威","张掖","甘南","临夏","平凉","定西","金昌"});
model.put("青海",newString[]{"西宁","海北","海西","黄南","果洛","玉树","海东","海南"});
model.put("湖北",newString[]{"武汉","宜昌","黄冈","恩施","荆州","神农架","十堰","咸宁","襄樊","孝感","随州","黄石","荆门","鄂州"});
model.put("湖南",newString[]{"长沙","邵阳","常德","郴州","吉首","株洲","娄底","湘潭","益阳","永州","岳阳","衡阳","怀化","韶山","张家界"});
model.put("浙江",newString[]{"杭州","湖州","金华","宁波","丽水","绍兴","雁荡山","衢州","嘉兴","台州","舟山","温州"});
model.put("江西",newString[]{"南昌","萍乡","九江","上饶","抚州","吉安","鹰潭","宜春","新余","景德镇","赣州"});
model.put("福建",newString[]{"福州","厦门","龙岩","南平","宁德","莆田","泉州","三明","漳州"});
model.put("贵州",newString[]{"贵阳","安顺","赤水","遵义","铜仁","六盘水","毕节","凯里","都匀"});
model.put("四川",newString[]{"成都","泸州","内江","凉山","阿坝","巴中","广元","乐山","绵阳","德阳","攀枝花","雅安","宜宾","自贡","甘孜州","达州","资阳","广安","遂宁","眉山","南充"});
model.put("广东",newString[]{"广州","深圳","潮州","韶关","湛江","惠州","清远","东莞","江门","茂名","肇庆","汕尾","河源","揭阳","梅州","中山","德庆","阳江","云浮","珠海","汕头","佛山"});
model.put("广西",newString[]{"南宁","桂林","阳朔","柳州","梧州","玉林","桂平","贺州","钦州","贵港","防城港","百色","北海","河池","来宾","崇左"});
model.put("云南",newString[]{"昆明","保山","楚雄","德宏","红河","临沧","怒江","曲靖","思茅","文山","玉溪","昭通","丽江","大理"});
model.put("海南",newString[]{"海口","三亚","儋州","琼山","通什","文昌"});
model.put("新疆",newString[]{"乌鲁木齐","阿勒泰","阿克苏","昌吉","哈密","和田","喀什","克拉玛依","石河子","塔城","库尔勒","吐鲁番","伊宁"});
}
}
2.定义获取省份的方法,创建一个Map集合,将上一步得到的映射集合赋值给它,使用Map集合的keySet()方法获取该集合中的所有键对象组成的Set集合,即为省分集合,创建一个Object型一维数组,使用Set接口的toArray()方法将Set集合转换为数组,返回此数组作为省份选择下拉列表的参数。
3.使用JComboBox类的setModel()方法为省份下拉列表添加省份信息,参数即为上一步中的获取省份方法。
4.定义根据省份获取市/县的方法,创建一个Map集合,将步骤1中得到的映射集合赋值给它,使用Map集合的get()方法获取指定键的值,即为市/县集合,创建一个String[]型一维数组,将市/县集合赋值给该数组。
5.定义省份下拉列表的选项状态更改事件,在该事件中通过JComboBox类的getSelectedItem()方法获取选中的省份,默认为省份集合中的第一个值,然后使用JComboBox类的removeAllItems()方法清空市/县列表,根据选中的省份获取市/县数组,最后使用JComboBox的setModel()方法重新添加市/县列表的值。
代码如下:
BackgroundPanel.java
复制代码代码如下:
importjava.awt.Graphics;
importjava.awt.Image;
importjavax.swing.JPanel;
/**
*带背景的面板组件
*
*@authorZhongWeiLee
*/
publicclassBackgroundPanelextendsJPanel{
/**
*
*/
privatestaticfinallongserialVersionUID=7758689434195492602L;
/**
*背景图片
*/
privateImageimage;
/**
*构造方法
*/
publicBackgroundPanel(){
super();
setOpaque(false);
setLayout(null);
}
/**
*设置图片的方法
*/
publicvoidsetImage(Imageimage){
this.image=image;
}
@Override
protectedvoidpaintComponent(Graphicsg){//重写绘制组件外观
if(image!
=null){
intwidth=getWidth();//获取组件大小
intheight=getHeight();
g.drawImage(image,0,0,width,height,this);//绘制图片与组件大小相同
}
super.paintComponent(g);//执行超类方法
}
}
SwingResourceManager.java
复制代码代码如下:
importjava.awt.Image;
importjava.awt.Toolkit;
importjava.io.BufferedInputStream;
importjava.io.ByteArrayOutputStream;
importjava.io.FileInputStream;
importjava.io.IOException;
importjava.io.InputStream;
importjava.util.HashMap;
importjava.util.Iterator;
importjavax.swing.ImageIcon;
/**
*Utilityclassformanagingresourcessuchascolors,fonts,images,etc.
*
*Thisclassmaybefreelydistributedaspartofanyapplicationorplugin.
*
*Copyright(c)2003-2004,Instantiations,Inc.
AllRightsReserved
*
*@authorscheglov_ke
*/
publicclassSwingResourceManager{
/**
*Mapsimagenamestoimages
*/
privatestaticHashMap
/**
*Returnsanimageencodedbythespecifiedinputstream
*@paramisInputStreamTheinputstreamencodingtheimagedata
*@returnImageTheimageencodedbythespecifiedinputstream
*/
privatestaticImagegetImage(InputStreamis){
try{
ByteArrayOutputStreambaos=newByteArrayOutputStream();
bytebuf[]=newbyte[1024*4];
while(true){
intn=is.read(buf);
if(n==-1)
break;
baos.write(buf,0,n);
}
baos.close();
returnToolkit.getDefaultToolkit().createImage(baos.toByteArray());
}catch(Throwablee){
returnnull;
}
}
/**
*Returnsanimagestoredinthefileatthespecifiedpathrelativetothespecifiedclass
*@paramclazzClassTheclassrelativetowhichtofindtheimage
*@parampathStringThepathtotheimagefile
*@returnImageTheimagestoredinthefileatthespecifiedpath
*/
publicstaticImagegetImage(Class
>clazz,Stringpath){
Stringkey=clazz.getName()+'|'+path;
Imageimage=m_ClassImageMap.get(key);
if(image==null){
if((path.length()>0)&&(path.charAt(0)=='/')){
StringnewPath=path.substring(1,path.length());
image=getImage(newBufferedInputStream(clazz.getClassLoader().getResourceAsStream(newPath)));
}else{
image=getImage(clazz.getResourceAsStream(path));
}
m_ClassImageMap.put(key,image);
}
returnimage;
}
/**
*Returnsanimagestoredinthefileatthespecifiedpath
*@parampathStringThepathtotheimagefile
*@returnImageTheimagestoredinthefileatthespecifiedpath
*/
publicstaticImagegetImage(Stringpath){
returngetImage("default",path);//$NON-NLS-1$
}
/**
*Returnsanimagestoredinthefileatthespecifiedpath
*@paramsectionStringThestoragesectioninthecache
*@parampathStringThepathtotheimagefile
*@returnImageTheimagestoredinthefileatthespecifiedpath
*/
publicstaticImagegetImage(Stringsection,Stringpath){
Stringkey=section+'|'+SwingResourceManager.class.getName()+'|'+path;
Imageimage=m_ClassImageMap.get(key);
if(image==null){
try{
FileInputStreamfis=newFileInputStream(path);
image=getImage(fis);
m_ClassImageMap.put(key,image);
fis.close();
}catch(IOExceptione){
returnnull;
}
}
returnimage;
}
/**
*Clearcachedimagesinspecifiedsection
*@paramsectionthesectiondoclear
*/
publicstaticvoidclearImages(Stringsection){
for(Iterator
Stringkey=I.next();
if(!
key.startsWith(section+'|'))
continue;
Imageimage=m_ClassImageMap.get(key);
image.flush();
I.remove();
}
}
/**
*Returnsaniconstoredinthefileatthespecifiedpathrelativetothespecifiedclass
*@paramclazzClassTheclassrelativetowhichtofindtheicon
*@parampathStringThepathtotheiconfile
*@returnIconTheiconstoredinthefileatthespecifiedpath
*/
publicstaticImageIcongetIcon(Class
>clazz,Stringpath){
returngetIcon(getImage(clazz,path));
}
/**
*Returnsaniconstoredinthefileatthespecifiedpath
*@parampathStringThepathtotheiconfile
*@returnIconTheiconstoredinthefileatthespecifiedpath
*/
publicstaticImageIcongetIcon(Stringpath){
returngetIcon("default",path);//$NON-NLS-1$
}
/**
*Returnsaniconstoredinthefileatthespecifiedpath
*@paramsectionStringThestoragesectioninthecache
*@parampathStringThepathtotheiconfile
*@returnIconTheiconstoredinthefileatthespecifiedpath
*/
publicstaticImageIcongetIcon(Stringsection,Stringpath){
returngetIcon(getImage(section,path));
}
/**
*Returnsaniconbasedonthespecifiedimage
*@paramimageImageTheoriginalimage
*@returnIconTheiconbasedontheimage
*/
publicstaticImageIcongetIcon(Imageimage){
if(image==null)
returnnull;
returnnewImageIcon(image);
}
}
MainFrame.java
复制代码代码如下:
importjava.awt.EventQueue;
importjava.awt.event.ItemEvent;
importjava.awt.event.ItemListener;
importjava.util.Map;
importjava.util.Set;
importjavax.swing.DefaultComboBoxModel;
importjavax.swing.JButton;
importjavax.swing.JComboBox;
importjavax.swing.JFrame;
importjavax.swing.JLabel;
importjavax.swing.JPanel;
importjavax.swing.JTextField;
importjavax.swing.SwingConstants;
importjavax.swing.UIManager;
importjavax.swing.border.TitledBorder;
public
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