我正在尝试创建一个类，当由 JPanel 调用时，它会创建一个多维数据集。不过，我所看到的是一种称为 ColorCube 的东西，它需要某种“Universe”和一个 Canvas，虽然我没有发现这个方法与 JPanel 兼容。
澄清一下，我不是问如何创建自定义 JComponent(确切地说)，也不是问如何添加颜色或旋转它，只是如何创建一个由JPanel 在屏幕上呈现一个立方体。
最佳答案
您真正需要的只是将x、y 和大小 传递给Cube 类，然后
采用这些参数并为第一个正方形构建角点数组，并为第二个移位的正方形构建角点数组。请参阅
Cube类中的getCubeOnePoints和getCubeTwoPoints方法。绘制第一个正方形。绘制第二个正方形，并连接点数组中的点。请参阅
Cube类中的drawCube方法。创建 Cube 类的实例并传递必要的参数，并绘制立方体。请参阅
CubePanel构造函数和paintComponent方法
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Point;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class CubePanel extends JPanel{
private static final int D_W = 400;
private static final int D_H = 400;
Cube cube;
public CubePanel() {
cube = new Cube(75, 75, 200, 50);
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
cube.drawCube(g);
}
@Override
public Dimension getPreferredSize() {
return new Dimension(D_W, D_H);
}
public class Cube {
int x, y, size, shift;
Point[] cubeOnePoints;
Point[] cubeTwoPoints;
public Cube(int x, int y, int size, int shift) {
this.x = x;
this.y = y;
this.size = size;
this.shift = shift;
cubeOnePoints = getCubeOnePoints();
cubeTwoPoints = getCubeTwoPoints();
}
private Point[] getCubeOnePoints() {
Point[] points = new Point[4];
points[0] = new Point(x, y);
points[1] = new Point(x + size, y);
points[2] = new Point(x + size, y + size);
points[3] = new Point(x, y + size);
return points;
}
private Point[] getCubeTwoPoints() {
int newX = x + shift;
int newY = y + shift;
Point[] points = new Point[4];
points[0] = new Point(newX, newY);
points[1] = new Point(newX + size, newY);
points[2] = new Point(newX + size, newY + size);
points[3] = new Point(newX, newY + size);
return points;
}
public void drawCube(Graphics g) {
g.drawRect(x, y, size, size);
g.drawRect(x + shift, y + shift, size, size);
// draw connecting lines
for (int i = 0; i < 4; i++) {
g.drawLine(cubeOnePoints[i].x, cubeOnePoints[i].y,
cubeTwoPoints[i].x, cubeTwoPoints[i].y);
}
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
JFrame frame = new JFrame();
frame.add(new CubePanel());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
}
更新
"what if i wanted this in a 3d where the cube could be walked around "
只需创建方法来移动所有的x或y并调用它，然后重新绘制。该方法可能类似于
public void shiftLeft() {
x -= SHIFT_INC;
for (Point p : cubeOnePoints) {
p.x -= SHIFT_INC;
}
for (Point p : cubeTwoPoints) {
p.x -= SHIFT_INC;
}
}
在下面的示例中，我只是在使用 ← 键的键绑定(bind)中调用它。
im.put(KeyStroke.getKeyStroke("LEFT"), "shiftLeft");
getActionMap().put("shiftLeft", new AbstractAction(){
public void actionPerformed(ActionEvent e) {
cube.shiftLeft();
repaint();
}
});
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Point;
import java.awt.event.ActionEvent;
import javax.swing.AbstractAction;
import javax.swing.InputMap;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.KeyStroke;
import javax.swing.SwingUtilities;
public class CubePanel extends JPanel{
private static final int D_W = 400;
private static final int D_H = 300;
Cube cube;
public CubePanel() {
cube = new Cube(75, 75, 50, 15);
InputMap im = getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW);
im.put(KeyStroke.getKeyStroke("RIGHT"), "shiftRight");
getActionMap().put("shiftRight", new AbstractAction(){
public void actionPerformed(ActionEvent e) {
cube.shiftRight();
repaint();
}
});
im.put(KeyStroke.getKeyStroke("LEFT"), "shiftLeft");
getActionMap().put("shiftLeft", new AbstractAction(){
public void actionPerformed(ActionEvent e) {
cube.shiftLeft();
repaint();
}
});
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
cube.drawCube(g);
}
@Override
public Dimension getPreferredSize() {
return new Dimension(D_W, D_H);
}
public class Cube {
private static final int SHIFT_INC = 5;
int x, y, size, shift;
Point[] cubeOnePoints;
Point[] cubeTwoPoints;
public Cube(int x, int y, int size, int shift) {
this.x = x;
this.y = y;
this.size = size;
this.shift = shift;
cubeOnePoints = getCubeOnePoints();
cubeTwoPoints = getCubeTwoPoints();
}
private Point[] getCubeOnePoints() {
Point[] points = new Point[4];
points[0] = new Point(x, y);
points[1] = new Point(x + size, y);
points[2] = new Point(x + size, y + size);
points[3] = new Point(x, y + size);
return points;
}
private Point[] getCubeTwoPoints() {
int newX = x + shift;
int newY = y + shift;
Point[] points = new Point[4];
points[0] = new Point(newX, newY);
points[1] = new Point(newX + size, newY);
points[2] = new Point(newX + size, newY + size);
points[3] = new Point(newX, newY + size);
return points;
}
public void shiftLeft() {
x -= SHIFT_INC;
for (Point p : cubeOnePoints) {
p.x -= SHIFT_INC;
}
for (Point p : cubeTwoPoints) {
p.x -= SHIFT_INC;
}
}
public void shiftRight() {
x += SHIFT_INC;
for (Point p : cubeOnePoints) {
p.x += SHIFT_INC;
}
for (Point p : cubeTwoPoints) {
p.x += SHIFT_INC;
}
}
public void drawCube(Graphics g) {
g.drawRect(x, y, size, size);
g.drawRect(x + shift, y + shift, size, size);
// draw connecting lines
for (int i = 0; i < 4; i++) {
g.drawLine(cubeOnePoints[i].x, cubeOnePoints[i].y,
cubeTwoPoints[i].x, cubeTwoPoints[i].y);
}
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
JFrame frame = new JFrame();
frame.add(new CubePanel());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
}
关于java - 如何在 Swing 中创建立方体？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/22549690/