Question

我必须多次画两个圆圈，每次都用不同的颜色。所以我想将颜色作为参数传递给paintComponent方法。但是如果我这样做，超类JPanel的方法将不会被覆盖。我该怎么办？这是我的代码：

public class Test extends JPanel{

    Ellipse2D oval;

    public void paintComponent(Graphics g){
        super.paintComponent(g);

        Graphics2D g2 = (Graphics2D) g;

        oval = new Ellipse2D.Double(137, 0, 40, 40);
        g2.setPaint(Color.black);    //color I want to pass as argument
        g2.fill(oval);

        oval = new Ellipse2D.Double(420, 0, 40, 40);
        g2.setPaint(Color.red);    //color I want to pass as argument
        g2.fill(oval);
    }
}

我想在调用构造函数时传递颜色：

public class MyFrame extends JFrame {
    Test t1, t2;

    public MyFrame(){
        //setSize, setTitle...

        t1 = new Test();  // would pass the colors in here
        t2 = new Test();  // would pass the colors in here

        add(t1);
        add(t2);
        setVisible(true);
    }
}

Answer 1

传递构造函数中的颜色并将它们保存在类成员变量中。然后重写paint组件以使用这些颜色绘制圆圈

所以在Test类中添加此代码

private java.awt.Color insideColor;
private java.awt. Color outsideColor;

public class Test (java.awt.Color inside, java.awt.Color outside){
    this.insideColor = inside;
    this.outsideColor = outside; 
}

使用paintComponent绘制图形，颜色为参数

1 个答案: