ActionListener和JButton

Question

因此，我有以下代码，每当我按下方形工具按钮时，它都应该在左上角绘制一个正方形，但是我什至无法获得控制台来打印其消息。 这使我认为actionListener甚至都不会响应我的点击。 有人可以帮忙吗？

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;

import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JMenuBar;
import javax.swing.JPanel;
import javax.swing.JTextField;

public class Game extends JPanel implements ActionListener {

private static final long serialVersionUID = 1L;

private GridPane gridPane;

private DragPanel drag;

    public boolean isMouseClicked = false;

    public static JMenuBar bar = new JMenuBar();

    public int gridY = 1;
    public int gridX = 1;

    public int x = 0,y = 0;


    public Game() {
        setLayout(new BorderLayout());

        OptionPanel options = new OptionPanel();
        options.addActionListener(this);
        add(options, BorderLayout.NORTH);


        gridPane = new GridPane();
        gridPane.setBorder(BorderFactory.createLineBorder(Color.white));
        add(gridPane);

        drag = new DragPanel();
        drag.setBorder(BorderFactory.createLineBorder(Color.white));
        drag.setBackground(new Color(100,100,125));
        add(drag,BorderLayout.WEST);

}

public static void main(String args[]) {
    Game game = new Game();

    JFrame frame = new JFrame();
    frame.setVisible(true);
    frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
    frame.setTitle("Game");
    frame.setAlwaysOnTop(true);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);


    frame.setLayout(new BorderLayout());
    frame.add(game);


}

@Override
public void actionPerformed(ActionEvent e) {
    if (e.getActionCommand().equalsIgnoreCase("grid")) {
        gridPane.setGridOn(!gridPane.isGridOn());
    }

    if (e.getActionCommand().equalsIgnoreCase("square")){
        gridPane.setSqaureOn(!gridPane.isSquareOn());
    }
    if (e.getActionCommand().equalsIgnoreCase("vgrid")){
        gridPane.setVertOn(!gridPane.isVertOn());
    }
    }

public class GridPane extends JPanel {


    private static final long serialVersionUID = 1L;
    private boolean gridOn = false;
    private boolean squareOn = false;
    private boolean vertOn = false;

    public GridPane() {
        setBackground(Color.BLACK);
    }

    public boolean isGridOn() {
        return gridOn;
    }

    public boolean isSquareOn(){

        return squareOn;
    }

    public boolean isVertOn(){

        return vertOn;
    }

    public void setGridOn(boolean value) {
        if (value != gridOn) {
            this.gridOn = value;
            repaint();
        }
    }

    public void setVertOn(boolean value){

        if (value != vertOn){
            this.vertOn = value;
            repaint();
        }
    }

    public void setSqaureOn(boolean value){
        if (value != squareOn){
            this.squareOn = value;
            repaint();
        }
    }

    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);

        Toolkit tk = Toolkit.getDefaultToolkit();

        if (gridOn) {
            System.out.println("Grid works");
            g.setColor(Color.white);
            for (int i = 0; i < tk.getScreenSize().height; i += 64){
                gridY++;
                g.drawLine(0, (64 * gridY), tk.getScreenSize().width,(64 * gridY));
            }
        }

        gridY = -1;

       gridX = -1;



       if (vertOn){
           System.out.println("vert grid works");
           g.setColor(Color.white);
           for (int ig = 0; ig < tk.getScreenSize().width; ig += 64){
              gridX++;
              g.drawLine((64 * gridX), 0,(64 * gridX),tk.getScreenSize().height);
          }
       }

       if (squareOn)
       {
           System.out.println("Square works");
           g.setColor(Color.red);
           g.fillRect(0,0,64,64);
       }
 }



}

public class DragPanel extends JPanel{

    OptionPanel op = new OptionPanel();


    public DragPanel(){
        add(op.squareButton);
        op.squareButton.setActionCommand("square");
    }

    public void addActionListener(ActionListener listener){
        op.squareButton.addActionListener(listener);
    }

}

public class OptionPanel extends JPanel {

    public JButton grid;

    public JButton vgrid;

    public JButton squareButton;

    public JTextField squareX;

    public JTextField squareY;

    public JTextField squareW;

    public JTextField squareH;

    public Square square = new Square();


    public OptionPanel() {

        //Sets the stuff for the panel
        setBackground(new Color(155,0,255));
        setLayout(new GridBagLayout());
        //end

        //The Show Grid Button Stuff
        grid = new JButton("Show Horizontal Grid");
        grid.setActionCommand("grid");
        //end

        //The vertical grid
        vgrid = new JButton("Show Vertical Grid");
        vgrid.setActionCommand("vgrid");
        //end

        //The Square tool button stuff
        squareButton = new JButton("Sqaure Tool");

        //end

        squareX = new JTextField(3);
        squareY = new JTextField(3);
        squareW = new JTextField(3);
        squareH = new JTextField(3);

        //The gridbagConstraints things
        GridBagConstraints gbc = new GridBagConstraints();
        gbc.anchor = GridBagConstraints.NORTH;


        //kind of like padding
        gbc.weighty = 1;

        //sets the positions
        gbc.gridx = 0;
        gbc.gridy = 0;

        //add it
        add(grid, gbc);

        //changes position for the second button
        gbc.gridx = -1;
        gbc.gridy = 0;

        // adds it
        add(vgrid,gbc);

        //end

        add(squareX,gbc);
        add(squareY,gbc);
        add(squareW,gbc);
        add(squareH,gbc);


    }

    public void addActionListener(ActionListener listener) {
        //adds action listeners
        grid.addActionListener(listener);
        vgrid.addActionListener(listener);

    }
}

Answer 1

DragPanel具有与Game 不同的 OptionPanel 。 我添加了一个实数作为参数，并用this来限定参考，更多是为了说明问题，而不是建议正确的用法。 正如HFOE所建议的那样，请使用Action将您的侦听器重构为尽可能本地的。

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JMenuBar;
import javax.swing.JPanel;
import javax.swing.JTextField;

public class Game extends JPanel implements ActionListener {

    private static final long serialVersionUID = 1L;
    private GridPane gridPane;
    private DragPanel drag;
    public boolean isMouseClicked = false;
    public static JMenuBar bar = new JMenuBar();
    public int gridY = 1;
    public int gridX = 1;
    public int x = 0, y = 0;

    public Game() {
        setLayout(new BorderLayout());

        OptionPanel options = new OptionPanel();
        options.addActionListener(this);
        add(options, BorderLayout.NORTH);

        gridPane = new GridPane();
        gridPane.setBorder(BorderFactory.createLineBorder(Color.white));
        add(gridPane);

        drag = new DragPanel(options);
        drag.setBorder(BorderFactory.createLineBorder(Color.white));
        drag.setBackground(new Color(100, 100, 125));
        add(drag, BorderLayout.WEST);
    }

    public static void main(String args[]) {
        Game game = new Game();
        JFrame frame = new JFrame();
        frame.setTitle("Game");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add(game);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        System.out.println(e);
        if (e.getActionCommand().equalsIgnoreCase("grid")) {
            gridPane.setGridOn(!gridPane.isGridOn());
        }

        if (e.getActionCommand().equalsIgnoreCase("square")) {
            gridPane.setSqaureOn(!gridPane.isSquareOn());
        }
        if (e.getActionCommand().equalsIgnoreCase("vgrid")) {
            gridPane.setVertOn(!gridPane.isVertOn());
        }
    }

    public class GridPane extends JPanel {

        private static final long serialVersionUID = 1L;
        private boolean gridOn = false;
        private boolean squareOn = false;
        private boolean vertOn = false;

        public GridPane() {
            setBackground(Color.BLACK);
        }

        public boolean isGridOn() {
            return gridOn;
        }

        public boolean isSquareOn() {
            return squareOn;
        }

        public boolean isVertOn() {
            return vertOn;
        }

        public void setGridOn(boolean value) {
            if (value != gridOn) {
                this.gridOn = value;
                repaint();
            }
        }

        public void setVertOn(boolean value) {
            if (value != vertOn) {
                this.vertOn = value;
                repaint();
            }
        }

        public void setSqaureOn(boolean value) {
            if (value != squareOn) {
                this.squareOn = value;
                repaint();
            }
        }

        @Override
        public Dimension getPreferredSize() {
            return new Dimension(320, 240);
        }

        @Override
        protected void paintComponent(Graphics g) {
            super.paintComponent(g);
            Toolkit tk = Toolkit.getDefaultToolkit();
            if (gridOn) {
                System.out.println("Grid works");
                g.setColor(Color.white);
                for (int i = 0; i < tk.getScreenSize().height; i += 64) {
                    gridY++;
                    g.drawLine(0, (64 * gridY), tk.getScreenSize().width, (64 * gridY));
                }
            }
            gridY = -1;
            gridX = -1;
            if (vertOn) {
                System.out.println("vert grid works");
                g.setColor(Color.white);
                for (int ig = 0; ig < tk.getScreenSize().width; ig += 64) {
                    gridX++;
                    g.drawLine((64 * gridX), 0, (64 * gridX), tk.getScreenSize().height);
                }
            }
            if (squareOn) {
                System.out.println("Square works");
                g.setColor(Color.red);
                g.fillRect(0, 0, 64, 64);
            }
        }
    }

    public class DragPanel extends JPanel {

        OptionPanel op;

        public DragPanel(OptionPanel op) {
            this.op = op;
            this.add(this.op.squareButton);
            this.op.squareButton.setActionCommand("square");
        }

        public void addActionListener(ActionListener listener) {
            System.out.println(listener);
            this.op.squareButton.addActionListener(listener);
        }
    }

    private static class Square {
    }

    private class OptionPanel extends JPanel {

        public JButton grid;
        public JButton vgrid;
        public JButton squareButton;
        public JTextField squareX;
        public JTextField squareY;
        public JTextField squareW;
        public JTextField squareH;
        public Square square = new Square();

        public OptionPanel() {

            //Sets the stuff for the panel
            setBackground(new Color(155, 0, 255));
            setLayout(new GridBagLayout());
            //end

            //The Show Grid Button Stuff
            grid = new JButton("Show Horizontal Grid");
            grid.setActionCommand("grid");
            //end

            //The vertical grid
            vgrid = new JButton("Show Vertical Grid");
            vgrid.setActionCommand("vgrid");
            //end

            //The Square tool button stuff
            squareButton = new JButton("Sqaure Tool");

            //end

            squareX = new JTextField(3);
            squareY = new JTextField(3);
            squareW = new JTextField(3);
            squareH = new JTextField(3);

            //The gridbagConstraints things
            GridBagConstraints gbc = new GridBagConstraints();
            gbc.anchor = GridBagConstraints.NORTH;


            //kind of like padding
            gbc.weighty = 1;

            //sets the positions
            gbc.gridx = 0;
            gbc.gridy = 0;

            //add it
            add(grid, gbc);

            //changes position for the second button
            gbc.gridx = -1;
            gbc.gridy = 0;

            // adds it
            add(vgrid, gbc);

            //end

            add(squareX, gbc);
            add(squareY, gbc);
            add(squareW, gbc);
            add(squareH, gbc);
        }

        public void addActionListener(ActionListener listener) {
            //adds action listeners
            grid.addActionListener(listener);
            vgrid.addActionListener(listener);
            squareButton.addActionListener(listener);
            System.out.println(listener);
        }
    }
}