我一直在使用箭头键移动,当我终于找到一个简单的教程时,图形将不会绘制圆圈,请任何帮助都将非常感谢!
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.geom.Ellipse2D;
import javax.swing.JPanel;
import javax.swing.Timer;
public class Plant extends JPanel implements ActionListener, KeyListener{
double x = 0, y = 0, velx = 0, vely = 0;
Timer t = new Timer(5, this);//calls action listener every 5 seconds
public Plant(){
t.start();
addKeyListener(this);
setFocusable(true);
setFocusTraversalKeysEnabled(false);//sets odd keys to act normal
}
public void drawGraphics(Graphics g){
super.paintComponent(g);
Graphics2D g2= (Graphics2D) g;
g2.fill(new Ellipse2D.Double(x, y, 70, 70));
}
public void actionPerformed(ActionEvent e){
repaint();//adds to x and y coordinates, then redraws them to the new coordinates
x += velx;
y += vely;
}
public void up(){
vely = -1.5;//casll when up key is pressed
velx = 0;
}
public void down(){
vely = 1.5;
velx = 0;
}
public void left(){
velx = -1.5;
vely = 0;
}
public void right(){
velx = 1.5;
vely = 0;
}
public void keyPressed(KeyEvent e){
int code = e.getKeyCode();
if(code == KeyEvent.VK_UP){
up();
}
if(code == KeyEvent.VK_DOWN){
down();
}
if(code == KeyEvent.VK_LEFT){
left();
}
if(code == KeyEvent.VK_RIGHT){
right();
}
}
public void keyReleased(KeyEvent e){}
public void keyTyped(KeyEvent e){}
}
这是我的第二个类的代码,用于绘制框架。
import javax.swing.JFrame;
public class BasicCharacterMovement{
public static void main(String args[]){
JFrame j = new JFrame();
Plant s = new Plant();
j.add(s);
j.setVisible(true);
j.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
j.setSize(800, 600);
}
}
答案 0 :(得分:1)
对于java中的自定义绘图,您需要使用paintComponent(Graphics g)
JComponent
。在Plant
中,您在drawGraphics
中绘制椭圆是错误的。将drawGraphics
替换为:
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.fill(new Ellipse2D.Double(x, y, 70, 70));
}
这有助于你。