java - 使对象在单击时出现

Question

我对 Java 编程非常陌生。我目前正在尝试制作一个游戏，其中白球不断出现在屏幕上，用户必须单击球并将其拖到 Canvas 的右侧以使其消失。我还没有写完代码，但我编写的代码不断使我的 Java 程序崩溃。谁能告诉我我的代码有什么问题以及为什么我的程序不断崩溃？谢谢!

public class BubbleGame extends GraphicsProgram
{

//~ Instance/static variables


private GRect field;
private GRect goal;
private GObject gobj;           /* The object being dragged */
private GPoint last;            /* The last mouse position  */

private RandomGenerator rgen = new RandomGenerator();

//~ Constructor ...........................................................

// ----------------------------------------------------------
/**
 * Creates a new BubbleGame object.
 */
public void init()
{
    //call method to create regions
    CreateRegions();

    //add mouse listeners
    addMouseListeners();

    //loop to add bubbles
    while (true)
    {
        //create a filled bubble
        GOval oval = new GOval (100, 100, 50, 50);
        oval.setFilled(true);
        oval.setColor(Color.WHITE);
        add(oval);

        //randomly generate coordinates within the field


        //add the bubble and pause 



    }
}


//~ Methods ...............................................................
public void CreateRegions(){

     //create and add the field with the size and color of your choice
     field = new GRect(0, 0, getWidth() * .75, getHeight());
     field.setFilled(true);
     field.setColor(Color.GREEN);
     add(field);

     //create and add the adjacent goal with the size and color of your choice
     goal = new GRect(493, 0, getWidth() * .25, getHeight());
     goal.setFilled(true);
     goal.setColor(Color.BLACK);
     add(goal);
    }



/* Called on mouse press to record the coordinates of the click */
public void mousePressed(MouseEvent e) {
    last = new GPoint(e.getPoint());
    gobj = getElementAt(last);
    //later add check that not dragging field or goal

}

/* Called on mouse drag to reposition the object */
public void mouseDragged(MouseEvent e) {
    if (gobj != null) {
        gobj.move(e.getX() - last.getX(), e.getY() - last.getY());
        last = new GPoint(e.getPoint());
    }    

}

/* Called on mouse drag to reposition the object */
public void mouseReleased(MouseEvent e) {
    //if gobj has a value and its coordinates are contained by goal, make it invisible  




}


}

Answer 1

您的 while 循环可能是其崩溃的原因。你可以考虑在这里设置一个 sleep ，这样你的应用程序就不会不断地使用CPU:

    while (true)
    {
        //create a filled bubble
        GOval oval = new GOval (100, 100, 50, 50);
        oval.setFilled(true);
        oval.setColor(Color.WHITE);
        add(oval);

        //randomly generate coordinates within the field


        //add the bubble and pause 


        Thread.sleep(100);
    }

您还不断添加 GOval 对象。我不知道 GraphicsProgram 类，但它也可能会导致您的内存在某些时候被填满。