JavaSwing学习笔记（二） JavaSwing学习笔记（二）

一：JLabel 新建MyIcon类实现Icon接口，再用此类实例化对象绘画一个圆，添加到JLabel中

package n1; import java.awt.Color; import java.awt.Component; import java.awt.Container; import java.awt.Graphics; import javax.swing.Icon; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.SwingConstants; import javax.swing.WindowConstants; public class MyICon implements Icon{private int width; private int height; public MyICon(int width,int height){this.width=width; this.height=height; } public void paintIcon(Component c, Graphics g, int x, int y) {g.fillOval(x, y, width, height); //用Graphics对象来填充椭圆 }@Override public int getIconWidth() {return this.width; }@Override public int getIconHeight() {return this.height; }public static void main(String[] args) {MyICon icon=new MyICon(15, 15); JLabel label=new JLabel("你好",icon,SwingConstants.CENTER); JFrame jf=new JFrame("窗口"); Container container=jf.getContentPane(); container.setBackground(Color.white); container.add(label); jf.setVisible(true); jf.setSize(300, 200); jf.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE); } }

运行结果：