我正在进行环形模拟。到目前为止，图像都在doDrawing()中绘制，但程序与服务器连接，因此我想根据服务器发送的内容从另一个类中绘制（生成）图像。出于测试目的，我在byte类的mousePressed()上标识了Roundabout数组。这有效我可以看到println中的spawnPedestrian()，但行人没有在JPanel上绘制。
我需要在spawnPedestrian()更改哪些内容才能使其正常工作？
Roundabout.java - 主要类
public class Roundabout extends JFrame{
Track track=new Track();
TrafficLight trafficLight1=new TrafficLight(1);
TrafficLight trafficLight3=new TrafficLight(3);
TrafficLight trafficLight2=new TrafficLight(2);
TrafficLight trafficLight4=new TrafficLight(4);
TrafficLight trafficLight5=new TrafficLight(5);
Car car=new Car(412, 750); // south to west
Car car2=new Car(50,400); // west to south
Car car3=new Car(700,290); //east to south
Car car4=new Car(470,750);
Bus bus=new Bus();
Bicycle bicycle=new Bicycle();
Pedestrian pedestrian = new Pedestrian(571,750);
ArrayList<Car> cars = new ArrayList<>();
//public ArrayList<TrafficLight> trafficLights = new ArrayList<>{trafficLight3}();
public static Map<Integer,TrafficLight> trafficLights = new HashMap<>();
byte[] array=new byte[]{0,2,1,1}; //test byte array
private Long startTime;
private long playTime = 4000;
private double i;
static TCPClient client;
Surface surface=new Surface();
class Surface extends JPanel {
private void doDrawing(Graphics g) {
Dimension size = getSize();
Insets insets = getInsets();
int w = size.width - insets.left - insets.right;
int h = size.height - insets.top - insets.bottom;
/* Draw the track first */
track.paint(g);
/* Draw a car */
//car.START_POS = new Point(412, 750);
car.setCarLane(Lane.topLane);
car.paint(g);
cars.add(car); //add to list
//car2.START_POS=new Point(50,400);
car2.carRotation=180;
car2.setCarLane(Lane.wsLane);
car2.paint(g);
cars.add(car2);
car3.carRotation=360;
car3.setCarLane(Lane.esLane);
car3.paint(g);
cars.add(car3);
car4.setCarLane(Lane.seLane);
car4.paint(g);
cars.add(car4);
/*Draw a bus*/
bus.paint(g);
/*Draw a bicycle */
bicycle.setBicyclePath(Lane.bicyclePath);
bicycle.paint(g);
/*Draw a pedestrian */
pedestrian.setPedestrianPath(Lane.pedesSePath);
pedestrian.paint(g);
/* Draw traffic light*/
trafficLight1.setPosition(520, 333);
trafficLight1.paint(g);
trafficLight3.setPosition(100, 275);
trafficLight3.paint(g);
trafficLight2.setPosition(100, 400);
trafficLight2.paint(g);
trafficLight4.setPosition(355, 535);
trafficLight4.paint(g);
trafficLight5.setPosition(404, 535);
trafficLight5.paint(g);
}
@Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
doDrawing(g);
}
}
public Roundabout(){
initUI();
trafficLights.put(trafficLight1.id, trafficLight1);
trafficLights.put(trafficLight2.id,trafficLight2);
trafficLights.put(trafficLight3.id,trafficLight3);
trafficLights.put(trafficLight4.id,trafficLight4);
trafficLights.put(trafficLight5.id,trafficLight5);
}
private void initUI() {
setTitle("Roundabout");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
add(surface);
//add start
this.addMouseListener(new MouseAdapter() {// empty implementation of all
// MouseListener`s methods
@Override
public void mousePressed(MouseEvent e) {
System.out.println(e.getX() + "," + e.getY());
ByteProtocol proto=new ByteProtocol();
proto.identifyByteArray(new byte []{0x01,0x02,0x01,0x00});
}
});
//end add
//setSize(580, 550);
setSize(1618,850);
setLocationRelativeTo(null);
}
public static void main(String[] args) {
//Swing thread
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
Roundabout roundabout=new Roundabout();
roundabout.setVisible(true);
roundabout.moveCar();
}
});
}
}
调用spawnPedestrian()的ByteProtocol.java方法。
public void identifyByteArray(byte [] inputArray) {
byte identifier=inputArray[0];
switch(identifier){
case vehicle:
System.out.println("Identifier: Vehicle");
decodeVehicleArray(inputArray);
break;
case trafficLight:
System.out.println("Traffic light");
decodeTrafficLightArray(inputArray);
break;
case vehicleRegistration:
System.out.println("Vehicle registration");
decodeVehicleRegistrationArray(inputArray);
break;
default: System.out.println("Unable to identify the byte array.");
break;
}
}
public void decodeVehicleArray(byte [] vehicleArray){
byte startPosition=vehicleArray[1];
String startPositionString = directions.get(startPosition);
System.out.println("Start position: "+startPositionString);
byte endPosition=vehicleArray[2];
String endPositionString = directions.get(endPosition);
System.out.println("End position: "+endPositionString);
byte vehicleType=vehicleArray[3];
String vehicleTypeString=vehicles.get(vehicleType);
System.out.println("Vehicle: "+vehicleTypeString);
Spawn spawn=new Spawn();
spawn.spawnPedestrian();
}
Spawn.java
public class Spawn {
Roundabout roundabout = new Roundabout();
public void spawnPedestrian(){
Pedestrian p = new Pedestrian(30,50);
System.out.println("Spawn me ");
p.setVisible(true);
roundabout.surface.add(p);
roundabout.surface.revalidate();
roundabout.surface.repaint();
roundabout.revalidate();
roundabout.repaint();
}
}
答案 0 :(得分：0)
当你在Spawn类中编写Roundabout roundabout = new Roundabout();时，你正在创建一个Roundabout类型的新对象（最后是一个新的JFrame），你不想要一个这种类型的新对象，你想要一个已经创建的对象。
您需要做的是通过getter引用Spawn类中的JPanel曲面。所以将此方法添加到Roundabout类并从Spawn调用它以获取其上下文并能够在其上绘制：
public static JPanel getSurface()
{
return surface;
}
然后在您的Spawn类中删除Roundabout roundabout = new Roundabout();，获取Surface JPanel对象并在其上绘图：
public class Spawn {
public void spawnPedestrian(){
Pedestrian p = new Pedestrian(30,50);
System.out.println("Spawn me ");
p.setVisible(true);
Roundabout.getSurface.add(p);
Roundabout.getSurface.revalidate();
Roundabout.getSurface.repaint();
Roundabout.getSurface.revalidate();
Roundabout.getSurface.repaint();
}
}
请注意，您需要将JPanel Surface对象设为静态。