bookmarklist.java

本程序用JavaME语言描述了一个运行在手机上的电子书系统

import javax.microedition.lcdui.Alert;
import javax.microedition.lcdui.AlertType;
import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.CommandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Image;
import javax.microedition.lcdui.List;
import javax.microedition.lcdui.TextBox;
import javax.microedition.lcdui.TextField;
import javax.microedition.rms.RecordEnumeration;
import javax.microedition.rms.RecordStore;


public class BookMarkList extends List implements CommandListener {					//书签列表类
	
	public final static int MAX_BM = 10;												//列表最大书签数
	private static TxtReader bookReader = null;										//主程序reference
	
	//命令集合
	private static Command CMD_back = new Command("返回",Command.BACK,1);
	private static Command CMD_enter = new Command("进入书签",Command.SCREEN,0);
	private static Command CMD_delete = new Command("删除",Command.SCREEN,2);
	private static Command CMD_edit = new Command("编辑", Command.SCREEN, 2);
	private static Command CMD_ok = new Command("确定", Command.OK, 1);
	private static Command CMD_delAll = new Command("删除所有", Command.SCREEN, 3);
	
	private static TextBox editBox = null;
	private static RecordStore rs = null;
	private boolean isEditMode = false;
	private int[] idList = new int[MAX_BM];											//列表选项对应书签的ID号
	
	private RecordStore default_rs = null;
	private String txtName = null;
	private Image ErrorIcon = null;
	private Image BookMarkIcon = null;
	
	public BookMarkList(String fileName, TxtReader tr){	
		super(fileName+" - 书签列表", List.IMPLICIT);
		this.txtName = fileName;
		bookReader = tr;
		addCommand(CMD_back);
		addCommand(CMD_enter);
		addCommand(CMD_delete);
		addCommand(CMD_edit);
		addCommand(CMD_delAll);
		setCommandListener(this);
		try{
			rs = RecordStore.openRecordStore(fileName, true);	
			ErrorIcon = Image.createImage("/icon/Error.png");
			BookMarkIcon = Image.createImage("/icon/BookMark.png");
		}catch (Exception e){															//不应如此简单处理
			e.printStackTrace();
		}
		update();
	}
	
	public void update(){																//刷新书签列表
		this.deleteAll();
		try{
			RecordEnumeration re = rs.enumerateRecords(null, null, false);
			BookMark bm;
			for (int i=0; i<re.numRecords(); ++i){
				bm = BookMark.deserialization(re.nextRecord());
				this.append(bm.getCento(), BookMarkIcon);
				idList[i] = bm.getID();
			}
			for (int i=re.numRecords(); i<MAX_BM; ++i){
				idList[i] = -1;
			}
			re.destroy();
		}catch (Exception e){
			e.printStackTrace();
		}
	}
	
	public int whenEnter(){
		BookMark bm = null;
		try{
			default_rs = RecordStore.openRecordStore(txtName.concat("fgfdg"),
					true);
			RecordEnumeration re = default_rs.enumerateRecords(null, null, false);
			bm = BookMark.deserialization(re.nextRecord());
			re.destroy();
			default_rs.deleteRecord(bm.getID());
			default_rs.closeRecordStore();
		}catch (Exception e){
			return 0;
		}
		return bm.getLine();
	}
	public void whenQuit(int line){
		try{
			default_rs = RecordStore.openRecordStore(txtName.concat("fgfdg"),
					true);
			RecordEnumeration re = default_rs.enumerateRecords(null, null, false);
			for (int i=0; i<re.numRecords(); ++i){
				default_rs.deleteRecord(re.nextRecordId());
			}
			re.destroy();
			BookMark bm = new BookMark();
			bm.setCento("");
			bm.setID(default_rs.getNextRecordID());
			bm.setLine(line);
			byte[] data = bm.serialization();
			default_rs.addRecord(data, 0, data.length);
			default_rs.closeRecordStore();
			//RecordStore.deleteRecordStore(txtName.concat("fgfdg"));
		}catch (Exception e){
			e.printStackTrace();
		}
	}
	
	private void back(){																//返回上级界面
		if (isEditMode){
			isEditMode = false;
			Display.getDisplay(bookReader).setCurrent(this);
			editBox = null;
		}else{
			Display.getDisplay(bookReader).setCurrent(bookReader.getDisplayable(TxtReader.READINGBORD));
		}
	}
	
	private void enter(){																//跳转到文本
		int select = this.getSelectedIndex();
		if (-1!=select){
			try{
				BookMark bm = BookMark.deserialization(rs.getRecord(idList[select]));
				ReadingBoard rb = (ReadingBoard)bookReader.getDisplayable(TxtReader.READINGBORD);
				Display.getDisplay(bookReader).setCurrent(rb);
				rb.goByMark(bm.getLine());
			}catch (Exception e){
				e.printStackTrace();
			}
		}
	}
	
	private void delete(){																//删除一条书签
		int select = this.getSelectedIndex();
		if (-1!=select){
			try{
				int id = idList[select];
				rs.deleteRecord(id);
			}catch (Exception e){
				e.printStackTrace();
			}
			update();
		}
		else{
			Display.getDisplay(bookReader).setCurrent(new Alert("错误", "请选择文件!", ErrorIcon, AlertType.ERROR));
		}
	}
	
	private void delAll(){
		int i=0;
		this.deleteAll();
		while (i!=BookMarkList.MAX_BM && idList[i]!=-1){
			try{
				rs.deleteRecord(idList[i]);
			}catch (Exception e){
				e.printStackTrace();
			}
			idList[i] = -1;
			++i;
		}
	}
	
	public void add(int line, String fs){												//添加一条书签
		boolean isFull = true;
		for (int i=0; i<MAX_BM; ++i)
			if (idList[i]==-1){
				isFull = false;
				break;
			}
		if (!isFull){
			try{
				BookMark bm = new BookMark(fs, line, rs.getNextRecordID());
				byte[] data = bm.serialization();
				rs.addRecord(data, 0, data.length);
			}catch (Exception e){
				e.printStackTrace();
			}
		}
		else{
			Display.getDisplay(bookReader).setCurrent(new Alert("错误", "书签列表已满!", ErrorIcon, AlertType.ERROR));
		}
		update();
	}
	
	private void edit(){																//编辑书签标题
		int pos = this.getSelectedIndex();
		if (-1!=pos){
			try{
				isEditMode = true;
				editBox = new TextBox("editBox", this.getString(pos), 40, TextField.ANY);
				editBox.addCommand(CMD_back);
				editBox.addCommand(CMD_ok);
				editBox.setCommandListener(this);
				Display.getDisplay(bookReader).setCurrent(editBox);
			}catch (Exception e){
				e.printStackTrace();
			}
		}else{
			Display.getDisplay(bookReader).setCurrent(new Alert("错误", "请选择文件!", ErrorIcon, AlertType.ERROR));
		}

	}
	
	private void ok(){																//编辑成功
		try{
			String s = editBox.getString();
			if (s==null || s.equals("")){
				Display.getDisplay(bookReader).setCurrent(new Alert("错误", "内容不能为空", ErrorIcon, AlertType.ERROR));
			}else{
				int select = this.getSelectedIndex();
				int id = idList[select];
				BookMark bm = BookMark.deserialization(rs.getRecord(id));
				rs.deleteRecord(id);
				bm.setCento(s);
				bm.setID(rs.getNextRecordID());
				byte[] data = bm.serialization();
				rs.addRecord(data, 0, data.length);
				update();
				Display.getDisplay(bookReader).setCurrent(this);
			}
		}catch (Exception e){
			e.printStackTrace();
		}
	}

	public void commandAction(Command c, Displayable d) {							//命令响应
		if (c==CMD_back){
			back();
		}else if (c==CMD_enter || c==List.SELECT_COMMAND){
			enter();
		}else if (c==CMD_delete){
			delete();
		}else if (c==CMD_edit){
			edit();
		}else if (c==CMD_ok){
			ok();
		}else if (c==CMD_delAll){
			delAll();
		}
	}
}