java - 使用 Swing 制作交通动画

Question

我一直在用 Java 编写交通模拟代码，现在想使用 swing 为模拟制作动画。我在主函数中调用 RoadNetwork 类，如下所示:

RoadNetwork roadnetwork = new RoadNetwork();

getcoords() 函数获取每个车辆的 xy 坐标位置，用于在 JPanel 上绘制车辆。我的主类的名字是AMEC。 spawned 变量显示车辆是否在模拟中生成，finished 变量指示车辆是否已退出模拟，vehiclecounter 变量显示整个模拟过程中的车辆总数，iconNumber 变量保存卡车图标表示车辆所在车辆的索引。分配给。

但是，当我运行主程序时，我没有收到任何视觉输出。我究竟做错了什么？另外，插入计时器并使用此程序更新我的 View 的最佳方法是什么？

    public class RoadNetwork extends JPanel {
// create array size of the amount of trucks generated
BufferedImage truckicons[] = new BufferedImage[100];
int populated[] = new int[100]; // array that indicates the identifier of the truck occupying the corresponding position in truckicons[]

public RoadNetwork() throws IOException{
for (int i = 0; i < 100; i++) {
    populated[i] = -1;  // initialization value
    truckicons[i] = ImageIO.read(getClass().getResource("Truck.png"));  // assign icon to each truck
}
}


protected void paintComponent (Graphics g) {
super.paintComponent(g);
int coords[] = new int[2];
for (int i = 0; i < 100; i++) {
    if (populated[i] != -1) {
    coords = AMEC.getcoord(populated[i]);
    g.drawImage(truckicons[i], coords[0], coords[1], this);
    }
}
for (int k = 0; k < AMEC.vehiclecounter; k++) {
    if (AMEC.vehicle[k].spawned == true && AMEC.vehicle[k].finished == false) { // if the truck is somewhere on the plant
    if (AMEC.vehicle[k].iconNumber == -1) { // if the vehicle hasn't been assigned an icon yet
        for (int l = 0; l < 100; l++) {
        if (populated[l] == -1) {
            populated[l] = k;
            AMEC.vehicle[k].iconNumber = l;
            break;
        }
        }
    }
    }
    else if (AMEC.vehicle[k].spawned == true && AMEC.vehicle[k].finished == true && AMEC.vehicle[k].iconNumber != -1) { // if the vehicle is done but hasn't been cleared from the icon list yet
    populated[AMEC.vehicle[k].iconNumber] = -1;
    AMEC.vehicle[k].iconNumber = -1;
    }
}
this.repaint();
}
}

Answer 1

"Also, what is the best way to insert a timer and updating my view with this program?"

使用javax.swing.Timer。基本结构很简单。这就像使用带有 ActionListener 的按钮，但 Timer 根据 持续时间每隔几毫秒触发 ActionEvent 你通过了。构造函数看起来像这样

Timer(int duration, ActionListener)

因此，示例用法如下所示，其中 50 是每个要触发的事件的持续时间

public RoadNetwork() {

    Timer timer = new Timer(50, new ActionListener(){
        public void actionPerformed(ActionEvent e) {
            // do something with image positions like loop through an array to move coordinates
            repaint();
        }
    });
    timer.start();
}

<小时/>

此外，无需在 paintComponent() 方法内调用 repaint()