calendarcanvas.java

一个手机日历程序的源代码,包括显示重要日期,节假日等

import java.util.*;
import javax.microedition.lcdui.*;

public class CalendarCanvas extends Canvas implements CommandListener
{
	public static Command nextMonthCmd = new Command("NextMonth",Command.SCREEN,1);
    public static Command prevMonthCmd = new Command("PrevMonth",Command.SCREEN,1);
    public static Command nextYearCmd = new Command("nextYear",Command.SCREEN,1);
    public static Command prevYearCmd = new Command("prevYear",Command.SCREEN,1);
    public static Command selectCmd = new Command("select",Command.EXIT,2);
    //周日到周六的文字
    private static String weekDays = new String("SunMonTueWenThuFriSat");

    private static Font[] fontShow={Font.getFont(Font.FACE_SYSTEM,Font.STYLE_PLAIN,Font.SIZE_SMALL),
        Font.getFont(Font.FACE_SYSTEM,Font.STYLE_PLAIN,Font.SIZE_SMALL),
	    Font.getFont(Font.FACE_SYSTEM,Font.STYLE_UNDERLINED,Font.SIZE_SMALL),
	    Font.getFont(Font.FACE_SYSTEM,Font.STYLE_UNDERLINED|Font.STYLE_BOLD,Font.SIZE_SMALL)};

    private static int[] clrBK=  {0x00ffffff,0x00999999,0x00ffffff,0x00999999};
    private static int[] clrFont={0x00000000,0x00000000,0x00000000,0x00000000};

    private static Font fontSelected=Font.getFont(Font.FACE_SYSTEM,Font.STYLE_BOLD,Font.SIZE_SMALL);
    private static int clrSelectedBK=0x00cccccc,clrSelectedFont = 0x00000000;
    //记录每月天数
    private static int[] daysOfMonth = {31,28,31,30,31,30,31,31,30,31,30,31};
    //日期选择事件处理对象
    protected DateSelectListener dateListener = null;
    //重要日期判断对象
    protected ImportDateFilter dateFilter = null;
    //月份变动事件处理对象
    protected MonthChangeListener monthListener =null;

    private int width,height;
    private int startX;//保存绘图开始的X坐标位置，便于日历居中显示
    private int iCellWidth,iCellHeight;//日历显示参数，每个日期所占空间
    private Calendar calTemp;//日期对象

    //当前焦点所在日期
    private int curYear,curMonth,curDay;

    public CalendarCanvas(Date date)
    {
		super();
	    addCommand(selectCmd);
	    addCommand(nextMonthCmd);
	    addCommand(prevMonthCmd);
	    addCommand(nextYearCmd);
	    addCommand(prevYearCmd);
	    setCommandListener(this);

	    calTemp = Calendar.getInstance();
	    if(date !=null)
		    calTemp.setTime(date);
	    curYear = calTemp.get(Calendar.YEAR);
	    curMonth = calTemp.get(Calendar.MONTH);
	    curDay = calTemp.get(Calendar.DAY_OF_MONTH);

	    iCellWidth = fontSelected.substringWidth(weekDays,0,3)+2;
	    iCellHeight=fontSelected.getHeight()+2;
    }


    public void setImportDateFilter(ImportDateFilter filter)
    {
		dateFilter = filter;
    }

    public void setDateSelectListener(DateSelectListener listener)
    {
		dateListener = listener;
    }

    public void setMonthChangeListener(MonthChangeListener listener)
    {
		monthListener = listener;
    }

    public Calendar getFocusDate()
    {
		calTemp.set(Calendar.YEAR,curYear);
	    calTemp.set(Calendar.MONTH,curMonth);
	    calTemp.set(Calendar.DAY_OF_MONTH,1);
	    return calTemp;
    }


    //在画布显示前保存屏幕尺寸
    protected void showNotify()
    {
		height = getHeight();
	    width = getWidth();
	    startX = (width- 7*iCellWidth)/2;
    }

    protected void paint(Graphics g)
    {
		//填充屏幕
	    g.setColor(0x00ffffff);
	    g.fillRect(0,0,width,height);
	    paintMonth(g);
    }

    protected void keyPressed(int keyCode)
    {
		int newDay = curDay;
	    switch(getGameAction(keyCode))
		{
			   case UP:
			   if(curDay>7)
			      newDay-=7;
		       break;
		       case DOWN:
			   if(curDay<=getDaysOfMonth(curYear,curMonth)-7)
			      newDay+=7;
		       break;
		       case LEFT:
		 	   if(curDay>1)
			      newDay --;
		       break;
		       case RIGHT:
			   if(curDay<getDaysOfMonth(curYear,curMonth))
			      newDay ++;
		       break;
		       case FIRE://确定选择某个日期
			      selectDate();
		       break;
	   }
	   if(newDay !=curDay)
	   {
		   curDay = newDay;
		   repaint();
	   }
    }


//处理菜单命令事件 
    public void commandAction(Command c,Displayable d)
    {
		if(c== nextYearCmd)//切换到下一年
		{
			curYear ++;
		    curMonth = 0;
		    notifyMonthChange();
	    }
	    else if(c==prevYearCmd)
	    {
			curYear --;
		    curMonth =11;
		    notifyMonthChange();
	    }
	    else if(c== nextMonthCmd)
		    nextMonth();
	    else if(c== prevMonthCmd)
		    prevMonth();
	    else if(c== selectCmd)
	    {
			selectDate();
	    }
        repaint();
    }

    //绘制当月的日历
    protected void paintMonth(Graphics g)
    {
		//显示当前年月日
	    int offsetY = 0; //保存绘图的Y轴坐标
	    g.setColor(clrSelectedFont);
	    g.setFont(fontSelected);
	    g.drawString(curYear+"/"+(curMonth+1),startX+iCellWidth*7/2,offsetY+2,Graphics.HCENTER|Graphics.TOP);
        //显示一周中每天的时间
	    g.setColor(clrSelectedFont);
	    g.setFont(fontSelected);
	    offsetY+=iCellHeight;
	    for(int i=0;i<7;i++)
		   g.drawSubstring(weekDays,i*3,3,startX+i*iCellWidth+1,offsetY,Graphics.LEFT|Graphics.TOP);
	    //显示当月所有日期
	    calTemp.set(Calendar.YEAR,curYear);
	    calTemp.set(Calendar.MONTH,curMonth);
	    int dayOW = 0;//保存星期
	    int clr1,clr2;//保存颜色值
	    Font ft;//保存字体
	    int type = ImportDateFilter.NORMALDAY;//日期的类型
	    int daysNum = getDaysOfMonth(curYear,curMonth);//得到当月的天数
	    offsetY+=iCellHeight;
        for(int i=1;i<=daysNum;i++)
	    {
			//分别对每天进行绘制
		    calTemp.set(Calendar.DAY_OF_MONTH,i);
	        dayOW = calTemp.get(Calendar.DAY_OF_WEEK);//得到当天是星期几
	        if(i==curDay)
		    {
				//当天是被选中的日期,用固定的字体和颜色进行显示
	            ft = fontSelected;
			    clr1 = clrSelectedBK;
			    clr2 = clrSelectedFont;
		    }

		    else
		    {
				//对于未选中的日期类型决定显示方式
		        if(dateFilter !=null)
			    {     
					//判断当天是否重要日期
			        type = dateFilter.isImportantDate(calTemp);
			    }

			    //type = i%4;
			    ft = fontShow[type];
			    clr1 = clrBK[type];
			    clr2 = clrFont[type];
		    }
	     	g.setFont(ft);
		    g.setColor(clr1);
    		g.fillRect(startX+(dayOW-1)*iCellWidth,offsetY,iCellWidth-1,iCellHeight-1);
	    	g.setColor(clr2);
		    g.drawString(String.valueOf(i),startX+(dayOW-1)*iCellWidth+iCellWidth/2,offsetY+1,Graphics.HCENTER|Graphics.TOP);
		    if(dayOW == Calendar.SATURDAY)
				offsetY+=iCellHeight;//转入下一周前增加Y轴坐标
	    }
    }

    //将月份改为下个月 
    protected void nextMonth()
    {
		if(curMonth<11)
		  curMonth ++;
	    else
	    {
			curMonth = 0;
		    curYear ++;
	    }
	    curDay = 1;
	    notifyMonthChange();
    }

    protected void prevMonth()
    {
		if(curMonth>0)
		   curMonth--;
	    else
	    {
			curMonth = 11;
		    curYear --;
	    }
	    curDay = 1;
	    notifyMonthChange();
    }

    //确定选择某个日期并引发事件
    protected void selectDate()
    {
		if(dateListener!=null)
	    {
			//引发事件
		    calTemp.set(Calendar.YEAR,curYear);
		    calTemp.set(Calendar.MONTH,curMonth);
		    calTemp.set(Calendar.DAY_OF_MONTH,curDay);
		    dateListener.dateSelected(this,calTemp);
	    }
    }
    //月份变化通知
    protected void notifyMonthChange()
    {
		if(monthListener !=null)
	    {
			calTemp.set(Calendar.YEAR,curYear);
		    calTemp.set(Calendar.MONTH,curMonth);
		    calTemp.set(Calendar.DAY_OF_MONTH,curDay);
		    monthListener.monthChanged(this,calTemp);
		}
    }

    //得到某年某月的天数
    protected int getDaysOfMonth(int year,int month)
    {
		if(month!=1)//如果不是2月，直接返回保存的当月天数
	        return daysOfMonth[month];
    	if(year%400==0||(year%100!=0 && year%4 ==0))
	    	return 29;
	    return daysOfMonth[month];
    }
}