Question

我试图从使用getter和setter的方法中获取值，但是无法让它返回除0之外的任何内容。这是我当前的代码：

int goodRow;

    int boardStatus[][] = { 
            {0, 0, 0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0, 0, 0},
    };

    public void placePiece(int column) {
        boolean goodInput = false;
        while(!goodInput) {
            for(int x = 5; x >= 0; x--) {
                if(boardStatus[x][column] == 0) {

                    setRow(x);

                    boardStatus[x][column] = 1;
                    goodInput = true;
                    break;

                }else if(boardStatus[0][x] == 1) {
                    goodInput = true;
                    break;
                }
            }
        }
    }

    public int getRow() {
        return goodRow;
    }

    public void setRow(int row) {
        goodRow = row;
    }

我的目标是能够调用getRow（）并检索方法中接受的x值。在我的placePiece()方法中，我使用setRow()方法获取x值，但到目前为止我的策略还没有完成。如何从我的方法中获取x值，以便我可以在程序的其他地方使用它？

- - - - - - - - 编辑

这是我的完整代码：

import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;

import javax.swing.JFrame;
import javax.swing.JPanel;

public class GUI extends JPanel implements MouseListener {

    moveMaker mover = new moveMaker();
    clickDetector click = new clickDetector();

    public void paintComponent(Graphics g) {
        super.paintComponent(g);

        g.setColor(Color.red);

        for(int y = 0; y < 6; y++) {
            for(int x = 0; x < 7; x++) {
                g.fillOval(x*70 + 10, y*70 + 10, 50, 50);
            }
        }       
        g.setColor(Color.BLACK);
        g.fillRect(0, 430, 500, 50);
        g.setColor(Color.white);
        g.drawString("CONNECT FOUR", 250, 450);
        g.setColor(Color.LIGHT_GRAY);
        click.paintPiece(g);
    }

    public void setUpGUI() {
        JFrame mainFrame = new JFrame();
        clickDetector click = new clickDetector();

        mainFrame.addMouseListener(click);
        mainFrame.addMouseListener(this);
        mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        mainFrame.setSize(500, 500);
        mainFrame.getContentPane().add(this);
        mainFrame.setVisible(true);
    }

    @Override
    public void mouseClicked(MouseEvent e) {
        repaint();
    }

    @Override
    public void mousePressed(MouseEvent e) {
    }
    @Override
    public void mouseReleased(MouseEvent e) {   
    }
    @Override
    public void mouseEntered(MouseEvent e) {
    }
    @Override
    public void mouseExited(MouseEvent e) {     
    }

    public static void main(String args[]) {
        GUI gui = new GUI();
        gui.setUpGUI();

    }

}

-

public class moveMaker {

    int goodRow;

    int boardStatus[][] = { 
            {0, 0, 0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0, 0, 0},
            {0, 0, 0, 0, 0, 0, 0},
    };

    public void placePiece(int column) {
        boolean goodInput = false;
        while(!goodInput) {
            for(int x = 5; x >= 0; x--) {
                if(boardStatus[x][column] == 0) {

                    setRow(x);

                    boardStatus[x][column] = 1;
                    goodInput = true;
                    break;

                }else if(boardStatus[0][x] == 1) {  
                    setRow(x);
                    goodInput = true;
                    break;
                }else{
                    System.out.println(x + " is taken.");
                }
            }
        }
    }

    public int getRow() {
        return goodRow;
    }

    public void setRow(int row) {
        goodRow = row;
    }

}

-

import java.awt.Graphics;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;


public class clickDetector implements MouseListener {

    moveMaker mover = new moveMaker();

    int mouseX = 0;

    @Override
    public void mouseClicked(MouseEvent e) {
        int xLocation = (e.getX() + 10)/70;
        mover.placePiece(xLocation);
        setMouseX(xLocation);
        System.out.println("Place piece at " + mouseX + ", " + mover.getRow() + ".");

    }

    public void paintPiece(Graphics g) {
        int x = (getMouseX()+10)/70;
        int y = (mover.getRow()+10)/70;
        g.fillOval(x, y, 50, 50);
        System.out.println(x + ", " + y);
    }

    public int getMouseX() {
        return mouseX;
    }

    public void setMouseX(int x) {
        mouseX = x;
    }

    @Override
    public void mousePressed(MouseEvent e) {
    }
    @Override
    public void mouseReleased(MouseEvent e) {
    }
    @Override
    public void mouseEntered(MouseEvent e) {    
    }
    @Override
    public void mouseExited(MouseEvent e) { 
    }
}

Answer 1

您尚未在此块中调用setRow(x)：

else if(boardStatus[0][x] == 1) {
    goodInput = true;
    break;
} else { //missing 
   ...
}

您还缺少else阻止。

编辑：

尝试调试方法setRow()并观察参数值。

Answer 2

我将您的代码放在一个名为Trial的类中，并添加了这个main（）：

public static void main(String[] args){
    Trial t = new Trial();
    for (int k = 0; k < 5; k++){
        t.placePiece(k);
        System.out.println(k + ", " + t.getRow());
    }
}

输出结果为：

0, 5
1, 5
2, 5
3, 5
4, 5

这是预期的输出：如果placePiece(n)的值为0（它总是如此），方法setRow(n)仅调用boardStatus[5][n]并结束循环; 当你调用getRow()时，该值将为5，即当你调用setter时循环所在的行！看看你的while循环的逻辑，它归结为

while(true){
     setRow(5);
     break;
}

或更简单

public void placePiece(int column){
     setRow(5);
}

Answer 3

从clickDetector类中删除mouseListener，并创建一个新方法;

public void setUpVariables(int x) {
    int xLocation = (x + 10)/70;
    mover.placePiece(xLocation);
    setMouseX(xLocation);
    System.out.println("Place piece at " + mouseX + ", " + mover.getRow() + ".");
}

现在，在您的GUI类中，在mouseClicked方法中，您可以添加

    click.setUpVariables(e.getX());

为了正确绘画，需要稍微调整paintPiece方法

public void paintPiece(Graphics g) {
    int x = (getMouseX())*70 + 10;
    int y = mover.getRow()*70 + 10;
    g.fillOval(x, y, 50, 50);
}

从方法中检索值

3 个答案: