以下程序创建一个窗口,窗口内放置一个面板,在面板中绘制直线和矩形
import javax.swing.*; import java.awt. *;
public class Test28{
public static void main(String[] args) {
MyFraine frame = new MyFrame();
}
}
class MyFrame extends JPanel {
public MyFrame(){
setTitle("Test28");
setSize(300, 200);
getContentPane().add( _____①____ ):
setVisible(ture);
}
}
class MyPanel extends JPanel {
Image myImg;
public void paintComponent(___② ){
g.setColor(Color.green);
g.drawLine(100, 50, 30, 50);
g.setColor(Color.red);
_____③____ (100. 50, 100, 46);
}
}