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J2ME屏幕不刷新？还有谁有J2ME,MIDP的下载地址？

楼主nik_Amis（...）2004-09-01 11:58:01 在 Java / J2ME 提问

我安装了
j2me_wireless_toolkit-2_0-windows.exe
j2sdk-1_4_1_03-windows-i586.exe
在公司的机器上运行正常，在家里面的机器出现画面不能刷新的问题
请问这是怎么回事儿？

另外，安装了以后我的程序找不到midp

MIDP需要另外安装么？

忘高手不惜赐教，谢了！问题点数：100、回复次数：14Top

1 楼zhushizu（从来就没有救世祖）回复于 2004-09-01 13:31:33 得分 11

是呀，我也是想了好久。。关注中。。。Top

2 楼prok（换换口味）回复于 2004-09-01 13:48:35 得分 11

MIDP不用另外安装啊。是不是模拟器死了？不刷新Top

3 楼zhang21cnboy（事了抚衣去，不留身与名）回复于 2004-09-01 14:07:09 得分 11

光这样,很难看出问题Top

4 楼shiyonggang（最熟悉的陌生人）回复于 2004-09-01 14:56:04 得分 11

9494Top

5 楼huangtaoxiao（huangtaoxiao）回复于 2004-09-01 15:36:51 得分 11

呵呵，肯定不是软件问题拉，屏幕刷新是要靠自己做的，不能指望别人的，是不是你的路径
配的不是很对阿
Top

6 楼nik_Amis（...）回复于 2004-09-01 19:28:05 得分 0

是两个问题，偶没有说清楚

1。不刷新
安装J2ME以后，打开Run MIDP Application ...这些程序，反映很慢
画面又不刷新的现象，比如关掉这个窗体，屏幕上还有它的部分图像

2.配置有问题
按照书上说的要配置CLASSPATH,PATH,SCREEN_DEPTH但是有些MIDP的路径我在安装J2ME的目录里面找不到
我强行按照书上说的配了环境变量
能打开javac但是编译的时候碰到midp的引用就抱错，说什么找不到，还要配什么HOME?

Top

7 楼nik_Amis（...）回复于 2004-09-01 19:29:50 得分 0

第1个问题用的是版本2，没有办法，我把J2ME完全卸载了重新找了另外一个版本1。4的好想，安装就不会又不刷新的问题

Top

8 楼dfrank（dfrank）回复于 2004-09-02 01:26:58 得分 11

很怪的问题 :)Top

9 楼huangtaoxiao（huangtaoxiao）回复于 2004-09-02 08:45:35 得分 20

呵呵，要是在标准的J2ME下做这个，就不用配路径了巴，新建一个工程，然后到J2ME的安装目录下面，把你要编译运行的文件放到相应的文件夹下面，然后有KTOOLBAR图形工具，build就可以了阿，真想配路径的话，你只是需要把，需要运行的模拟器和验证程序，配在Path下面，把官方提供的类，配到classpath下面就行了，用不着多想，就和配普通的Java是一样的阿^-^Top

10 楼nik_Amis（...）回复于 2004-09-02 10:14:11 得分 0

E:\j2me\wtk\apps\TimerDemo\src\TimerDemo.java:1: package javax.microedtition.midlet does not exist

import javax.microedtition.midlet.*;

^

E:\j2me\wtk\apps\TimerDemo\src\TimerDemo.java:2: package javax.microedtition.lcdui does not exist

import javax.microedtition.lcdui.*;

^

E:\j2me\wtk\apps\TimerDemo\src\TimerDemo.java:5: cannot resolve symbol

symbol : class MIDlet

location: class TimerDemo

public class TimerDemo extends MIDlet

^

E:\j2me\wtk\apps\TimerDemo\src\TimerDemo.java:7: cannot resolve symbol

symbol : class Display

location: class TimerDemo

Display display;

^

E:\j2me\wtk\apps\TimerDemo\src\TimerDemo.java:36: cannot resolve symbol

symbol : class Canvas

location: class TimerDemo.StarField

class StarField extends Canvas

^

E:\j2me\wtk\apps\TimerDemo\src\TimerDemo.java:67: cannot resolve symbol

symbol : class Graphics

location: class TimerDemo.StarField

protected void paint(Graphics g)

^

E:\j2me\wtk\apps\TimerDemo\src\TimerDemo.java:21: cannot resolve symbol

symbol : class viod

location: class TimerDemo

protected viod pauseApp() {}

^

E:\j2me\wtk\apps\TimerDemo\src\TimerDemo.java:13: cannot resolve symbol

symbol : variable Display

location: class TimerDemo

display=Display.getDisplay(this);

^

E:\j2me\wtk\apps\TimerDemo\src\TimerDemo.java:26: cannot resolve symbol

symbol : method notifyDestroyed ()

location: class TimerDemo

notifyDestroyed();

^

E:\j2me\wtk\apps\TimerDemo\src\TimerDemo.java:45: cannot resolve symbol

symbol : method getHeight ()

location: class TimerDemo.StarField

height=getHeight();

^

E:\j2me\wtk\apps\TimerDemo\src\TimerDemo.java:46: cannot resolve symbol

symbol : method getWidth ()

location: class TimerDemo.StarField

width=getWidth();

^

E:\j2me\wtk\apps\TimerDemo\src\TimerDemo.java:47: cannot resolve symbol

symbol : variable heigh

location: class TimerDemo.StarField

stars=new int[heigh];

^

E:\j2me\wtk\apps\TimerDemo\src\TimerDemo.java:60: cannot resolve symbol

symbol : method newxtInt ()

location: class java.util.Random

stars[0]=(generator.newxtInt()%(3*width))/2;

^

E:\j2me\wtk\apps\TimerDemo\src\TimerDemo.java:65: cannot resolve symbol

symbol : method repaint ()

location: class TimerDemo.StarField

repaint();

^

14 errors

com.sun.kvem.ktools.ExecutionException

Build failed
Top

11 楼nik_Amis（...）回复于 2004-09-02 10:14:55 得分 0

源程序，那位大虾帮俺看看谢谢了！

import javax.microedtition.midlet.*;
import javax.microedtition.lcdui.*;
import java.util.*;

public class TimerDemo extends MIDlet
{
Display display;
StarField field=new StarField();
FieldMover mover=new FieldMover();
Timer timer=new Timer();
public TimerDemo()
{
display=Display.getDisplay(this);
}
protected void destroyApp(boolean unconditional) {}
protected void startApp()
{
display.setCurrent(field);
timer.schedule(mover,100,100);
}
protected viod pauseApp() {}
public void exit()
{
timer.cancel();
destroyApp(true);
notifyDestroyed();
}
class FieldMover extends TimerTask
{
public void run()
{
field.scroll();
}
}

class StarField extends Canvas
{
int height,width;
int[] stars;
Random generator=new Random();
boolean painting=false;

public StarField()
{
height=getHeight();
width=getWidth();
stars=new int[heigh];
for (int i=0;i<height;i++)
{
stars[i]=-1;
}
}
public void scroll()
{
if (painting) return;
for (int i=height-1;i>0;--i)
{
stars[i]=stars[i-1];
}
stars[0]=(generator.newxtInt()%(3*width))/2;
if (stars[0]>=width)
{
stars[0]=-1;
}
repaint();
}
protected void paint(Graphics g)
{
painting=true;
g.setColor(0,0,0);
g.fillRect(0,0,width,height);
g.setColor(255,255,255);
for (int y=0;y<height;++y)
{
int x=stars[y];
if (x==-1) continue;
g.drawLine(x,y,x,y);
}
painting=false;
}
protected void keyPressed(int keyCode)
{
exit();
}
}
}Top

12 楼nik_Amis（...）回复于 2004-09-02 10:20:32 得分 0

晕！低级拼写错误-_-#

stars[0]=(generator.newxtInt()%(3*width))/2;
这句那里错了？

Top

13 楼minajo21（大眼睛）回复于 2004-09-02 10:31:17 得分 14

@_@Top

14 楼nik_Amis（...）回复于 2004-09-02 11:29:17 得分 0

解决了

多谢楼上各位了

Top