list实例

1.下面两个java文件是一个实例，直接放在工程下就可以直接看到效果。 
  效果图见下面的上传文件 
Cls_CellList. java主要使用了ListCellRenderer这个东西，源代码如下: 
package com.sun.lwuit.uidemo;   
import com.sun.lwuit.Component;   
import com.sun.lwuit.Container;   
import com.sun.lwuit.Label;   
import com.sun.lwuit.List;   
import com.sun.lwuit.events.ActionListener;   
import com.sun.lwuit.layouts.BorderLayout;   
import com.sun.lwuit.layouts.BoxLayout;   
import com.sun.lwuit.list.ListCellRenderer;   
import com.sun.lwuit.plaf.Border;   
public class Cls_CellList {   
    static public List createList(CellList[] celllist,int stringWidth,ActionListener lAListner) {   
        List list = new List(celllist);   
        list.getStyle().setBgTransparency(0);   
        //开始显示List   
        list.setListCellRenderer(new CellRenderer(celllist[0].getColumm().length,stringWidth));   
        //添加消息处理   
        list.addActionListener(lAListner);   
        return list;   
    }   
static public class CellRenderer extends Container implements ListCellRenderer {   
        //初始化显示Columm每个字段的Label   
        private Label[] lbColumm ;   
        private Label focus = new Label("");   
        public CellRenderer(int size,final int stringWidth) {   
            lbColumm = new Label[size];   
            setLayout(new BorderLayout());   
            Container cnt = new Container(new BoxLayout(BoxLayout.X_AXIS));   
            for(int i=0;i<lbColumm.length;i++)//定义显示Columm每个字段的Label   
            {   
                lbColumm[i]=new Label(){   
                    //很多人都问怎么setWidth平时没什么用，这是因为setWidth必须在重载的时候使用，LWUIT奇怪的地方之一！   
                    public void setWidth(int arg0) {   
                        super.setWidth(stringWidth);   
                    }   
                };   
                lbColumm[i].getStyle().setFgColor(getStyle().getFgSelectionColor());//设置为最亮的颜色   
                lbColumm[i].getStyle().setBgTransparency(0);//设置背景为透明，不然会遮挡focus影响外观   
                cnt.addComponent(lbColumm[i]);   
            }   
               
            addComponent(BorderLayout.CENTER, cnt);   
            focus.getStyle().setBgTransparency(255);   
            focus.getStyle().setBorder(Border.createRoundBorder(10, 10));   
        }   
        public Component getListCellRendererComponent(List list, Object value, int index, boolean isSelected) {   
            CellList cellList = (CellList) value;   
            for(int i=0;i<lbColumm.length;i++)   
            {   
                lbColumm[i].setText(cellList.getColumm()[i]);   
            }   
            return this;   
        }   
        public Component getListFocusComponent(List list) {   
            //Columm栏不具备选中事件   
            if(list.getSelectedIndex()>0)   
                return focus;   
            return null;   
        }   
    }   
    static public class CellList {   
        //保存该列的所有字段   
        private String[] lstColumm;   
        public CellList(String[] columm) {   
           //复制数组   
           lstColumm=new String[columm.length];   
           System.arraycopy(columm, 0, lstColumm, 0, lstColumm.length);   
        }   
        //返回该列   
        public String[] getColumm(){   
           return lstColumm;   
        }   
    }   
}  

ListDemo.java源代码如下： 





/*  
* Copyright ?2008 Sun Microsystems, Inc. All rights reserved.  
* Use is subject to license terms.  
*  
*/  
package com.sun.lwuit.uidemo;   
import com.sun.lwuit.Command;   
import com.sun.lwuit.Font;   
import com.sun.lwuit.Form;   
import com.sun.lwuit.List;   
import com.sun.lwuit.events.ActionEvent;   
import com.sun.lwuit.events.ActionListener;   
import com.sun.lwuit.layouts.BorderLayout;   
public class ListDemo implements ActionListener  {   
    public Form form = new Form("ListDemo");   
    private  Command backCommand = new Command("Back", 1);   
    private String[][] myList = {   
        {"  标题1  ","  标题2  ","  标题3  "," 标题4 "},//表格每个字段的显示长度由标题栏的最长一项决定   
        {"aaaaa","bbbbb","ccccc","ddddd"},   
        {"11111","222222","33333","444444"},   
        {"aaaaa","bbbbb","ccccc","ddddd"},   
        {"11111","222222","33333","444444"},   
        {"aaaaa","bbbbb","ccccc","ddddd"},   
        {"11111","222222","33333","444444"},   
        {"aaaaa","bbbbb","ccccc","ddddd"},   
        {"11111","222222","33333","444444"}   
    };   
    ListDemo(){   
        form.setLayout(new BorderLayout());   
        form.addCommand(backCommand);   
        form.setScrollable(true);   
        //定义列表的列数   
        Cls_CellList.CellList[] cellArray = new Cls_CellList.CellList[myList.length];   
        for (int i = 0; i < cellArray.length; i++) {   
            cellArray[i] = new Cls_CellList.CellList(myList[i]);   
        }   
           
        //取得Columm的标题栏中长度最大的一项   
        int stringWidth=0;   
        for(int i=0;i<myList[0].length;i++)   
        {   
            int size=Font.getDefaultFont().stringWidth(myList[0][i])+8;//给最长的字段留点空余   
            if(stringWidth<size)   
                stringWidth=size;   
        }   
        //构造list并且显示   
        form.addComponent(BorderLayout.CENTER,Cls_CellList.createList(cellArray,stringWidth,new ListActionListener()));   
        form.setCommandListener(this);   
    }   
    public void actionPerformed(ActionEvent arg0) {     
        Command command=arg0.getCommand();   
        if(command==backCommand)   
            UIDemoMIDlet.backToMainMenu();   
    }   
    //按下列表触发的事件   
    private class ListActionListener implements ActionListener {   
        public void actionPerformed(ActionEvent evt) {   
            int selectIndex=((List)evt.getSource()).getSelectedIndex();   
            String str="";   
            for(int i=0;i<myList[selectIndex].length;i++)   
                str=str+myList[selectIndex][i]+"_";   
            form.setTitle(str);   
        }   
    }   
}