我正在一个项目中工作，我必须绘制包含箭头和节点的图形！我做了一个扩展JPanel箭头和节点的类，我做了一个JSplitPane 让菜单在左边，图表在右边！当我添加两个面板时，其中一个是可见的。
箭头面板类：
public class ArrowPanel extends JPanel{
int barb;
double phi;
double x1;
double y1;
double x2;
double y2;
double xcentre;
double ycentre;
double x3;
double y3;
double x4;
double y4;
public ArrowPanel(double x1,double y1,double x2, double y2 ,double x3,double y3 ,double x4 ,double y4){
barb = 30; // barb length
phi = Math.PI/6; // 30 degrees barb angle
this.x1=x1;
this.y1=y1;
this.x2=x2;
this.y2=y2;
this.x3=x3;
this.y3=y3;
this.x4=x4;
this.y4=y4;
this.setVisible(true);
this.setOpaque(false) ;
this.setLayout(new GridBagLayout());
System.out.println(" c est marché");} protected void paintComponent(Graphics g){
super.paintComponent(g);
Graphics2D g2 = (Graphics2D)g;
Graphics2D g3 = (Graphics2D)g;
g2.setStroke(new BasicStroke(7));
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g3.setStroke(new BasicStroke(7));
g3.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
int w = getWidth();
int h = getHeight();
double theta, x, y;
double a = 0;
double b = 0;
xcentre=(x1 + x2)/2 ;
ycentre=(y1 + y2)/2 ;
double z3 = x1;
double k3 = y1;
k3=a*z3+b;
a=(y2-y1)/(x2-x1);
b=y1-a*x1;
System.out.println( "a="+ a);
System.out.println( "b="+ b);
double a1 = -1/a;
double b1 = ycentre-a1*xcentre;
g2.setPaint(Color.RED);
g3.setPaint(Color.RED);
g3.draw(new Line2D.Double(x3, y3, x4, y4));
g2.draw(new Line2D.Double(x1, y1, x2, y2));
theta = Math.atan2(y2 - y1, x2 - x1);
double theta2=Math.atan2(y4 - y3, x4 - x3);
drawArrow(g2, theta, x2, y2);
drawArrow(g3, theta2, x4, y4);
g2.setPaint(Color.GREEN);
g2.draw(new Line2D.Double(xcentre - 5, a*(xcentre - 5)+ b, xcentre+5, a*(xcentre+5)+b));
g2.drawString("rad1", getX(), getY());
g2.draw(new Line2D.Double(xcentre - 7, a1*(xcentre - 7)+ b1, xcentre+7, a1*(xcentre+7)+b1));
xcentre=(x3 + x4)/2 ;
ycentre=(y3 + y4)/2 ;
z3 = x3;
k3 = y3;
k3=a*z3+b;
a=(y4-y3)/(x4-x3);
b=y3-a*x3;
System.out.println( "a="+ a);
System.out.println( "b="+ b);
a1 = -1/a;
b1 = ycentre-a1*xcentre;
g3.draw(new Line2D.Double(xcentre - 5, a*(xcentre - 5)+ b, xcentre+5, a*(xcentre+5)+b));
g3.draw(new Line2D.Double(xcentre - 7, a1*(xcentre - 7)+ b1, xcentre+7, a1*(xcentre+7)+b1));
System.out.println("bahamas");
}
private void drawArrow(Graphics2D g2, double theta, double x0, double y0)
{
double x = x0 - barb * Math.cos(theta + phi);
double y = y0 - barb * Math.sin(theta + phi);
g2.draw(new Line2D.Double(x0, y0, x, y));
x = x0 - barb * Math.cos(theta - phi);
y = y0 - barb * Math.sin(theta - phi);
g2.draw(new Line2D.Double(x0, y0, x, y));
}}`
这是元素类：
public class ElementMenu extends JPanel {private static final long serialVersionUID = 1L;private int largeur;
private Color couleur;
private Color couleurActif;
private Color couleurNormal;
private String texte;
private String Ident;
public ElementMenu(String texte,String Ident, Color couleurNormal, Color couleurActif, int taille) {
this.couleur=couleurNormal;
this.couleurNormal=couleurNormal;
this.couleurActif=couleurActif;
this.texte=texte;
this.Ident=Ident ;
largeur=taille;
this.setSize(new Dimension(largeur, largeur ));
this.setOpaque(false);
this.setLayout(new BorderLayout());
ajouterListener();
}
private void ajouterListener(){
addMouseListener(new MouseListener() {public void mouseClicked(MouseEvent e) {}
public void mouseReleased(MouseEvent e) {}
public void mousePressed(MouseEvent e) {}
public void mouseExited(MouseEvent e) {
couleur=couleurNormal;
repaint();
}
public void mouseEntered(MouseEvent e) {
couleur=couleurActif;
setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
repaint();
}
});}public void paint(Graphics arg0) {
super.paint(arg0);
Graphics2D g2d = (Graphics2D) arg0;
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2d.setColor(couleur);
g2d.setStroke(new BasicStroke(3));
GradientPaint gradient = new GradientPaint(largeur / 2, 4, couleur, (largeur) / 2, 4 + largeur, new Color(255,255,255,200));
g2d.setPaint(gradient);
g2d.fillOval(4, 4, largeur, largeur);
gradient = new GradientPaint(largeur / 2, 4, Color.RED, largeur / 2, 4 + largeur / 2, new Color(couleur.getRed(), couleur.getGreen(), couleur.getBlue(), 0));
g2d.setPaint(gradient);
g2d.fillOval(4+largeur/5, 4, 5*largeur/8, largeur/3);
g2d.setColor(Color.WHITE);
g2d.setFont(new Font("Calibri", Font.BOLD, 14));
FontMetrics fm = g2d.getFontMetrics();
int x = 10;
int y = (fm.getAscent() + (this.getHeight() -
(fm.getAscent() + fm.getDescent())) / 2 );
int x0 = (this.getWidth() - fm.stringWidth(Ident)) / 4 +25;
int y0 = (fm.getAscent() + (this.getHeight() -
(fm.getAscent() + fm.getDescent())) / 2 -55);
g2d.drawString(texte, x+15, y);
g2d.drawString(Ident, x0, y0);}}`
这是主要的：
public static void main(String[] args) {
Fenetre splitPaneTest1 = new Fenetre();
splitPaneTest1.setSize(1000,600);
splitPaneTest1.show();
List<ElementMenu> items = new ArrayList<ElementMenu>();
items.add(new ElementMenu("rad1","ACTION", new Color(19, 73, 140), new Color(162, 198, 232), 150));
items.add(new ElementMenu("rad2","GOAL",new Color(19, 73, 140), new Color(162, 198, 232), 150));
items.add(new ElementMenu("rad3","KNOWLEDGE", new Color(19, 73, 140), new Color(162, 198, 232), 150));
splitPaneTest1.getContentPane().add(jSplitPane1, BorderLayout.CENTER);
jSplitPane1.setOpaque(false);
jSplitPane1.add(new MenuCirculaire(Color.blue, 800, 600, 200, 150,items),JSplitPane.RIGHT);
jSplitPane1.add(new ArrowPanel(363.5,335,460.5,168,540,171,635.5,335),JSplitPane.RIGHT);
jSplitPane1.add(new MenuGauche(),JSplitPane.LEFT);
}