Question

java 不兼容的类型

import java.awt.Graphics;
import java.applet.*;
import java.awt.*;
import java.awt.event.*;
public class liwuqi extends Applet implements ItemListener
{
CheckboxGroup cg;
Checkbox red, yellow, green, blue;
Color co;
List lc;
String colorname[] = {"红色","黄色","绿色","蓝色","橙色","黑色","粉色"};
String colors[] = {Color.red,Color.yellow,Color.green,Color.blue,Color.orange,Color.black,Color.pink};
int a;
public void init()
{
cg = new CheckboxGroup();
co = Color.red;

red = new Checkbox("红色", cg, true);
red.addItemListener(this);
add(red);

yellow = new Checkbox("黄色", cg, false);
yellow.addItemListener(this);
add(yellow);

green = new Checkbox("绿色", cg, false);
green.addItemListener(this);
add(green);

blue = new Checkbox("蓝色", cg, false);
blue.addItemListener(this);
add(blue);

lc = new List(5,false);
lc.addItemListener(this);
for(int i = 0; i<colorname.length; i++)
{
lc.add(colorname[i]);
}
add(lc);
}

public void itemStateChanged(ItemEvent e)
{
if(e.getSource() == red) co = Color.red;
if(e.getSource() == yellow) co = Color.yellow;
if(e.getSource() == green) co = Color.green;
if(e.getSource() == blue) co = Color.blue;

showStatus(lc.getSelectedItem() + ":顺序号" + lc.getSelectedIndex());
a = lc.getSelectedIndex();
repaint();
}

public void paint(Graphics g)
{
g.setColor(co);
g.fillRect(50, 80, 50, 50);
g.setColor(colors[a]);
g.fillOval(270, 100, 50, 50);
}
}
在教材上抄了一个程序，有错误，请各位大侠帮忙调一下。我都弄了好久了。

Answer 1

说明当前类型无法强制转换为另外一个类型。
如:
if（1=2），这个就会出现不兼容的类型，因为if需要的类型是波尔类型，而1=2是一个赋值语句，所以就不兼容，必须改为”1==2“，这个才是一个波尔类型，结果为false。
备注：每个类型都有基本的要求，如果不满足转换要求都会报不兼容的类型错误。

Answer 2

import java.awt.Graphics;
import java.applet.*;
import java.awt.*;
import java.awt.event.*;
public class liwuqi extends Applet implements ItemListener
{
CheckboxGroup cg;
Checkbox red, yellow, green, blue;
Color co;
List lc;
String colorname[] = {"红色","黄色","绿色","蓝色","橙色","黑色","粉色"};
Color colors[] = {Color.red,Color.yellow,Color.green,Color.blue,Color.orange,Color.black,Color.pink};
int a;
public void init()
{
cg = new CheckboxGroup();
co = Color.red;

red = new Checkbox("红色", cg, true);
red.addItemListener(this);
add(red);

yellow = new Checkbox("黄色", cg, false);
yellow.addItemListener(this);
add(yellow);

green = new Checkbox("绿色", cg, false);
green.addItemListener(this);
add(green);

blue = new Checkbox("蓝色", cg, false);
blue.addItemListener(this);
add(blue);

lc = new List(5,false);
lc.addItemListener(this);
for(int i = 0; i<colorname.length; i++)
{
lc.add(colorname[i]);
}
add(lc);
}

public void itemStateChanged(ItemEvent e)
{
if(e.getSource() == red) co = Color.red;
if(e.getSource() == yellow) co = Color.yellow;
if(e.getSource() == green) co = Color.green;
if(e.getSource() == blue) co = Color.blue;

showStatus(lc.getSelectedItem() + ":顺序号" + lc.getSelectedIndex());
a = lc.getSelectedIndex();
repaint();
}

public void paint(Graphics g)
{
g.setColor(co);
g.fillRect(50, 80, 50, 50);
g.setColor(colors[]);
g.fillOval(270, 100, 50, 50);
}
}
颜色的地方错了一个小地方

Answer 3

java.awt.Color

Color.red,Color.yellow,Color.green,Color.blue,Color.orange,Color.black,Color.pink

这些返回的全部都是Color型的对象 你吧Color型的对象放到String的数组里...所以 当然不兼容了

Answer 4

String colors[]
改成
Color colors[]