Question

这是交易，基本上我必须有一个代码，有一个桶可以捕捉落下的水果，每次它捕获它你得到一个新的水果落点。

所以我知道如何让水桶移动，以及如果水果到达水底后如何让它再次移动。但是，我不知道如何让它真正下降。到目前为止，我有一个开关，但不知道如何处理它。我在随机的地方突然出现了水果，这是一个开始。无论如何，这是我的代码。所有帮助赞赏。再次，当其中一个到达底部时，我需要随机掉落水果。

import java.awt.Color;
import java.awt.event.KeyEvent;

import acm.graphics.GOval;
import acm.graphics.GPolygon;
import acm.graphics.GRect;
import acm.program.GraphicsProgram;
import acm.util.RandomGenerator;

import java.awt.event.*;

public class FruitCatcher extends GraphicsProgram {
	private static final int APPLET_WIDTH = 500;
	private static final int APPLET_HEIGHT = 500;
	private static final int BUCKET_X = 250;
	private static final int BUCKET_Y = 500;
	private static final int BUCKET_SPEED = 10;
	private static final int BUCKET_SPEED2 = -10;

	private GPolygon Bucket;

	public void init() {
		setSize(APPLET_WIDTH, APPLET_HEIGHT);
		addKeyListeners();
	}

	public void run() {
		RandomGenerator random = new RandomGenerator();

		makeBucket();
		for (int i = 1; i <= 3; i++) {

			int randomX = random.nextInt(0, 300 - 20);

			addFruit(i, randomX, 0);
		}
		while (true)
			;

	}

	public void makeBucket() {
		Bucket = new GPolygon(BUCKET_X, BUCKET_Y);
		Bucket.addVertex(-60, 0);
		Bucket.addVertex(-70, -85);
		Bucket.addVertex(10, -85);
		Bucket.addVertex(0, 0);

		add(Bucket);
		Bucket.setFilled(true);
		Bucket.setFillColor(Color.GRAY);
	}

	public void addFruit(int a, int x, int y) {

		switch (a) {
		case 1:
			GRect Banana = new GRect(x, y, 10, 60);
			Banana.setColor(Color.YELLOW);
			Banana.setFilled(true);
			add(Banana);
			break;
		case 2:
			GOval lime = new GOval(x, y, 20, 20);
			lime.setColor(Color.GREEN);
			lime.setFilled(true);
			add(lime);
			break;
		case 3:
			GOval Orange = new GOval(x, y, 30, 30);
			Orange.setColor(Color.ORANGE);
			Orange.setFilled(true);
			add(Orange);
		}

	}

	public void keyPressed(KeyEvent event) {
		int keyCode = event.getKeyCode();
		switch (keyCode) {
		case KeyEvent.VK_LEFT:
			if (Bucket.getX() > 0) {
				Bucket.move(-BUCKET_SPEED, 0);
			}
			break;
		case KeyEvent.VK_RIGHT:
			if (Bucket.getX() < APPLET_WIDTH) {
				Bucket.move(BUCKET_SPEED, 0);
			}
			break;
		}
	}
}

在我的代码中你可以看到一段时间（真实）我只是假设这是我写的地方。但是，我实际上会在那里失去一点点。

Answer 1

你需要保留一份对所有成果的引用列表，以便以后可以操作它们
游戏循环的每次迭代，将每个果实移动

你可能想要实现一些计时机制，以便结果速度不依赖于CPU速度。

package jsyn;

import java.awt.Color;
import java.awt.Component;
import java.awt.event.KeyEvent;
import java.util.ArrayList;
import java.util.List;

import acm.graphics.GOval;
import acm.graphics.GPolygon;
import acm.graphics.GRect;
import acm.program.GraphicsProgram;
import acm.util.RandomGenerator;

import java.awt.event.*;

public class FruitCatcher extends GraphicsProgram {
private static final int APPLET_WIDTH = 500;
private static final int APPLET_HEIGHT = 500;
private static final int BUCKET_X = 250;
private static final int BUCKET_Y = 500;
private static final int BUCKET_SPEED = 10;
private static final int BUCKET_SPEED2 = -10;

//Speed of fruit falling
private static final int FRUIT_PX_PER_MS = 10;

private GPolygon Bucket;

public void init() {
    setSize(APPLET_WIDTH, APPLET_HEIGHT);
    addKeyListeners();
    fruits = new ArrayList<Component>();
}

// Keep list of fruits
List<GObject> fruits;

public void run() {
    RandomGenerator random = new RandomGenerator();

    makeBucket();
    for (int i = 1; i <= 3; i++) {

        int randomX = random.nextInt(0, 300 - 20);

        addFruit(i, randomX, 0);
    }

    long last = System.currentTimeMillis();
    while (true) {
        long current = System.currentTimeMillis();
        update(current - last);
        last = current;
    }
}

void update(long delta) {
    for (GObject fruit : fruits) {
        //this code may not work, replace with code that moves fruit down
        fruit.setLocation(fruit.getX(), fruit.getY() + delta * FRUIT_PX_PER_MS);
    }
}

public void makeBucket() {
    Bucket = new GPolygon(BUCKET_X, BUCKET_Y);
    Bucket.addVertex(-60, 0);
    Bucket.addVertex(-70, -85);
    Bucket.addVertex(10, -85);
    Bucket.addVertex(0, 0);

    add(Bucket);
    Bucket.setFilled(true);
    Bucket.setFillColor(Color.GRAY);
}

public void addFruit(int a, int x, int y) {

    switch (a) {
    case 1:
        GRect Banana = new GRect(x, y, 10, 60);
        Banana.setColor(Color.YELLOW);
        Banana.setFilled(true);
        add(Banana);
        fruits.add(Banana);
        break;
    case 2:
        GOval lime = new GOval(x, y, 20, 20);
        lime.setColor(Color.GREEN);
        lime.setFilled(true);
        add(lime);
        fruits.add(lime);
        break;
    case 3:
        GOval Orange = new GOval(x, y, 30, 30);
        Orange.setColor(Color.ORANGE);
        Orange.setFilled(true);
        add(Orange);
        fruits.add(Orange);
    }

}

public void keyPressed(KeyEvent event) {
    int keyCode = event.getKeyCode();
    switch (keyCode) {
    case KeyEvent.VK_LEFT:
        if (Bucket.getX() > 0) {
            Bucket.move(-BUCKET_SPEED, 0);
        }
        break;
    case KeyEvent.VK_RIGHT:
        if (Bucket.getX() < APPLET_WIDTH) {
            Bucket.move(BUCKET_SPEED, 0);
        }
        break;
    }
}
}

如何在此代码中移动随机对象？

1 个答案: