void jButton2_actionPerformed(ActionEvent e) {
Color backcolor = JColorChooser.showDialog
(this,"选择颜色",contentPane.getBackground());
if(backcolor !=null){
contentPane.setBackground(backcolor);
}
}
为什么还要报:
"Frame1.java": cannot resolve symbol: variable contentPane in class example.Frame1 at line 97, column 24 这样的错误呢?
开头也写了:
import java.awt.*;
import java.awt.event.*;
Color backcolor = JColorChooser.showDialog
(this,"选择颜色",contentPane.getBackground());
if(backcolor !=null){
contentPane.setBackground(backcolor);
}
}
为什么还要报:
"Frame1.java": cannot resolve symbol: variable contentPane in class example.Frame1 at line 97, column 24 这样的错误呢?
开头也写了:
import java.awt.*;
import java.awt.event.*;
你仔细察看一下