Java中的图形和图形2D

Question

我在使用java中的方法时，更改我创建的钻石的颜色时遇到问题。我不知道如何通过使用方法来继承或更正它。我只是希望它成为面向对象的，我不知道如何正确地做到这一点。请帮助我。

package Trial;

import javax.swing.*;
import java.awt.*;

public class ColorRed extends JApplet {
    public GradientPaint gradientPaint;
    public void paint(Graphics g){
        super.paint(g);
        Graphics2D g2 = (Graphics2D)g;
        GradientPaint black = new GradientPaint(50,20,Color.BLACK,50,50,Color.BLACK);
        blackDiamond(g2,black);
        GradientPaint yellowOrange = new GradientPaint(50,20,Color.YELLOW,50,50,Color.RED);
        redDiamond(g2,yellowOrange);

    }

    public void blackDiamond(Graphics2D g2,GradientPaint gradientPaint){
        int a [] = {100,50,100,150,100};
        int b [] = {10,60,110,60,10};
        setGradientPaint(gradientPaint);
        g2.setPaint(getGradientPaint());
        fillPolygon(a,b,5,g2);
    }
    public void redDiamond(Graphics2D g2,GradientPaint gradientPaint){
        int a2 [] = {100,60,100,140,100};
        int b2 [] = {20,60,100,60,20};
        setGradientPaint(gradientPaint);
        g2.setPaint(getGradientPaint());
        fillPolygon(a2,b2,5,g2);
    }

    public void fillPolygon(int a [], int b [] ,int c,Graphics2D g2){

        getGraphics().fillPolygon(a,b,c);
    }

    public GradientPaint getGradientPaint() {
        return gradientPaint;
    }

    public void setGradientPaint(GradientPaint gradientPaint) {
        this.gradientPaint = gradientPaint;
    }
}

这是我尝试创建的面向对象的代码，但它不继承渐变颜料的颜色。

enter image description here

这是我的代码的结果

此代码尚未创建多个方法

import javax.swing.*;
import java.awt.*;

public class ColorRed extends JApplet {
    public GradientPaint gradientPaint;
    public void paint(Graphics g){
        super.paint(g);
        Graphics2D g2 = (Graphics2D)g;
        int a [] = {100,50,100,150,100};
        int b [] = {10,60,110,60,10};
        g.fillPolygon(a,b,5);
        GradientPaint red = new GradientPaint(50,10,Color.RED,10,70,Color.ORANGE);
        g2.setPaint(red);
        int a2 [] = {100,60,100,140,100};
        int b2 [] = {20,60,100,60,20};
        g.fillPolygon(a2,b2,5);

    }
}

这是我想要的结果：enter image description here

我只想更正它以便组织起来，这样就不会在paint方法中声明所有局部变量，而只想用不同的方法将其分开，问题是颜色不会改变。请帮助我，非常感谢。 :)

Answer 1

也许像这样组织它，以便于更改颜色：

package Trial;

import javax.swing.*;
import java.awt.*;

public class ColorRed extends JApplet {
    private GradientPaint black;    
    private GradientPaint yellowOrange; 

    public void init() {
        setBlack(new GradientPaint(50,20,Color.BLACK,50,50,Color.BLACK));
        setYellowOrange(GradientPaint(50,20,Color.YELLOW,50,50,Color.RED));
    }

    public setBlack(GradientPaint black) {
        this.black = black;
    }

    public setYellowOrange(GradientPaint yellowOrange) {
        this.yellowOrange = yellowOrange;
    }

    public void paint(Graphics g){
        super.paint(g);
        Graphics2D g2 = (Graphics2D)g;
        blackDiamond(g2,black);
        redDiamond(g2,yellowOrange);
    }

    public void blackDiamond(Graphics2D g2,GradientPaint gradientPaint){
        int a [] = {100,50,100,150,100};
        int b [] = {10,60,110,60,10};
        g2.setPaint(gradientPaint);
        fillPolygon(a,b,5,g2);
    }
    public void redDiamond(Graphics2D g2,GradientPaint gradientPaint){
        int a2 [] = {100,60,100,140,100};
        int b2 [] = {20,60,100,60,20};
        g2.setPaint(gradientPaint);
        fillPolygon(a2,b2,5,g2);
    }

    public void fillPolygon(int a [], int b [] ,int c,Graphics2D g2){

        g2.fillPolygon(a,b,c);
    }
}

很遗憾，我没有找到在线挥杆赛跑者进行测试。

Answer 2

我修改了Adder's答案（按公告方式工作），因此它无需使用JApplet（也被标记为已弃用）就可以使用。我在其他地方添加了一些评论。

    import java.awt.Color;
    import java.awt.Dimension;
    import java.awt.GradientPaint;
    import java.awt.Graphics;
    import java.awt.Graphics2D;

    import javax.swing.JFrame;
    import javax.swing.JPanel;
    import javax.swing.SwingUtilities;

    public class ColorRed extends JPanel {
       private GradientPaint black;
       private GradientPaint yellowOrange;

       JFrame                frame = new JFrame();

       public static void main(String[] args) {
          SwingUtilities.invokeLater(() -> new ColorRed().init());
       }

       public void init() {

          frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

          // set the panel size
          setPreferredSize(new Dimension(500, 500));
          // add panel to frame.
          frame.add(this);
          // adjust frame and subcomponents
          frame.pack();
          // center on screen
          frame.setLocationRelativeTo(null);
          frame.setVisible(true);
          setBlack(new GradientPaint(50, 20, Color.BLACK, 50, 50, Color.BLACK));
          setYellowOrange(new GradientPaint(50, 20, Color.YELLOW, 50, 50, Color.RED));
       }

       public void setBlack(GradientPaint black) {
          this.black = black;
       }

       public void setYellowOrange(GradientPaint yellowOrange) {
          this.yellowOrange = yellowOrange;
       }
       // use paintComponent(g) and not  paint(g)
       public void paintComponent(Graphics g) {
          super.paintComponent(g);
          Graphics2D g2 = (Graphics2D) g;
          blackDiamond(g2, black);
          redDiamond(g2, yellowOrange);
       }

       public void blackDiamond(Graphics2D g2, GradientPaint gradientPaint) {
          int a[] = { 100, 50, 100, 150, 100
          };
          int b[] = { 10, 60, 110, 60, 10
          };
          g2.setPaint(gradientPaint);
          fillPolygon(a, b, 5, g2);
       }
       public void redDiamond(Graphics2D g2, GradientPaint gradientPaint) {
          int a2[] = { 100, 60, 100, 140, 100
          };
          int b2[] = { 20, 60, 100, 60, 20
          };
          g2.setPaint(gradientPaint);
          fillPolygon(a2, b2, 5, g2);
       }

       public void fillPolygon(int a[], int b[], int c, Graphics2D g2) {

          g2.fillPolygon(a, b, c);
       }
    }