沃梦达 / 编程问答 / Java问题 / 正文

重写为 MVC 后 GUI 无法正常工作

Java问题
2022-01-01

GUI not working after rewriting to MVC(重写为 MVC 后 GUI 无法正常工作)

本文介绍了重写为 MVC 后 GUI 无法正常工作的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我正在练习 MVC 风格的编程.我在一个文件中有一个 Mastermind 游戏，运行良好(可能除了检查"按钮在开始时不可见).

I'm practicing MVC style programming. I have a Mastermind game in a single file, working fine (maybe apart of the fact that "Check" button is invisible at start).

http://paste.pocoo.org/show/226726/

但是，当我将其重写为模型、视图、控制器文件时 - 当我点击空 Pin(应该更新，并用新颜色重新绘制)时 - 会发生注意事项.任何人都可以在这里看到任何问题吗?我试过将 repaint() 放在不同的地方，但它根本不起作用:/

But when I've rewritten it to model, view, controller files - and when I click on empty Pin (that should be updated, and repainted with new color) - noting happens. Can anybody see any problems here ? I've tried placing repaint() in different places, but it simply does not work at all :/

主要:

public class Main { 
    public static void main(String[] args){
        Model model = new Model();
        View view = new View("Mastermind", 400, 590, model);
        Controller controller = new Controller(model, view); 
        view.setVisible(true);
    }
}

型号:

import java.util.Random;

public class Model{
    static final int
    LINE = 5,
    SCORE = 10, OPTIONS = 20;
    Pin pins[][] = new Pin[21][LINE];
    int combination[] = new int[LINE];
    int curPin = 0;
    int turn = 1;
    Random generator = new Random();
    int repaintPin;
    boolean pinsRepaint=false;
    int pinsToRepaint;
    boolean isUpdate = true, isPlaying = true, isRowFull = false;
    static final int HIT_X[] = {270,290,310,290,310}, HIT_Y[] = {506,496,496,516,516};

    public Model(){

        for ( int i=0; i < SCORE; i++ ){
            for ( int j = 0; j < LINE; j++ ){
                pins[i][j] = new Pin(20,0);
                pins[i][j].setPosition(j*50+30,510-i*50);
                pins[i+SCORE][j] = new Pin(8,0);
                pins[i+SCORE][j].setPosition(HIT_X[j],HIT_Y[j]-i*50);
            }
        }
        for ( int i=0; i < LINE; i++ ){
            pins[OPTIONS][i] = new Pin( 20, i+2 );
            pins[OPTIONS][i].setPosition( 370,i * 50 + 56);
        }

    }

    void fillHole(int color) {
        pins[turn-1][curPin].setColor(color+1);
        pinsRepaint = true;
        pinsToRepaint = turn;
        curPin = (curPin+1) % LINE;
        if (curPin == 0){
            isRowFull = true;
        }
        pinsRepaint = false;
        pinsToRepaint = 0;
    }

    void check() {
        int junkPins[] = new int[LINE], junkCode[] = new int[LINE];
        int pinCount = 0, pico = 0;

        for ( int i = 0; i < LINE; i++ ) {
            junkPins[i] = pins[turn-1][i].getColor();
            junkCode[i] = combination[i];
        }
        for ( int i = 0; i < LINE; i++ ){
            if (junkPins[i]==junkCode[i]) {
                pins[turn+SCORE][pinCount].setColor(1);
                pinCount++;
                pico++;
                junkPins[i] = 98;
                junkCode[i] = 99;
            }
        }
        for ( int i = 0; i < LINE; i++ ){
            for ( int j = 0; j < LINE; j++ )
                if (junkPins[i]==junkCode[j]) {
                    pins[turn+SCORE][pinCount].setColor(2);
                    pinCount++;
                    junkPins[i] = 98;
                    junkCode[j] = 99;
                    j = LINE;
            }
        }
        pinsRepaint = true;
        pinsToRepaint = turn + SCORE;
        pinsRepaint = false;
        pinsToRepaint=0;

        if ( pico == LINE ){
            isPlaying = false;
        }
        else if ( turn >= 10 ){
                isPlaying = false;
        }
        else{
            curPin = 0;
            isRowFull = false;
            turn++;
        }
    }

    void combination() {
        for ( int i = 0; i < LINE; i++ ){
          combination[i] = generator.nextInt(6) + 1;
        }
    }
}

class Pin{
    private int color, X, Y, radius;

    public Pin(){
        X = 0; Y = 0; radius = 0; color = 0;
    }

    public Pin( int r,int c ){
        X = 0; Y = 0; radius = r; color = c;
    }

    public int getX(){
        return X;
    }

    public int getY(){
        return Y;
    }

    public int getRadius(){
        return radius;
    }

    public void setRadius(int r){
        radius = r;
    }

    public void setPosition( int x,int y ){
        this.X = x ;
        this.Y = y ;
    }
    public void setColor( int c ){
        color = c;
    }
    public int getColor() {
        return color;
    }
}

查看:

import java.awt.*;
import javax.swing.*;

public class View extends Frame{  
    Model model;
    JButton checkAnswer;
    private JPanel button;
    private static final Color COLORS[] = {Color.black, Color.white, Color.red, Color.yellow, Color.green, Color.blue, new Color(7, 254, 250)};

    public View(String name, int w, int h, Model m){
        model = m;
        setTitle( name );
        setSize( w,h );
        setResizable( false );
        this.setLayout(new BorderLayout());

        button = new JPanel();
        button.setSize( new Dimension(400, 100));
        button.setVisible(true);
        checkAnswer = new JButton("Check");
        checkAnswer.setSize( new Dimension(200, 30));
        button.add( checkAnswer );
        this.add( button, BorderLayout.SOUTH);
        button.setVisible(true);
    }

    @Override
    public void paint( Graphics g ) {
        g.setColor( new Color(238, 238, 238));
        g.fillRect( 0,0,400,590);

        for ( int i=0; i < model.pins.length; i++ ) {
            paintPins(model.pins[i][0],g);
            paintPins(model.pins[i][1],g);
            paintPins(model.pins[i][2],g);
            paintPins(model.pins[i][3],g);
            paintPins(model.pins[i][4],g);
        }
    }

    @Override
    public void update( Graphics g ) {
        if ( model.isUpdate ) {
            paint(g);
        }
        else {
            model.isUpdate = true;
            paintPins(model.pins[model.repaintPin-1][0],g);
            paintPins(model.pins[model.repaintPin-1][1],g);
            paintPins(model.pins[model.repaintPin-1][2],g);
            paintPins(model.pins[model.repaintPin-1][3],g);
            paintPins(model.pins[model.repaintPin-1][4],g);
        }
    }

    void repaintPins( int pin ) {
        model.repaintPin = pin;
        model.isUpdate = false;
        repaint();
    }

    public void paintPins(Pin p, Graphics g ){
        int X = p.getX();
        int Y = p.getY();
        int color = p.getColor();
        int radius = p.getRadius();
        int x = X-radius;
        int y = Y-radius;

        if (color > 0){
            g.setColor( COLORS[color]);
            g.fillOval( x,y,2*radius,2*radius );
        }
        else{
            g.setColor( new Color(238, 238, 238) );
            g.drawOval( x,y,2*radius-1,2*radius-1 );
        }
        g.setColor( Color.black );
        g.drawOval( x,y,2*radius,2*radius );
    }
}

控制器:

import java.awt.*;
import java.awt.event.*;

public class Controller implements MouseListener, ActionListener { 
    private Model model;
    private View view;

    public Controller(Model m, View v){ 
        model = m;
        view = v;

        view.addWindowListener( new WindowAdapter(){
            public void windowClosing(WindowEvent e){
            System.exit(0);
        } });
        view.addMouseListener(this);
        view.checkAnswer.addActionListener(this);
        model.combination();
    }

    public void actionPerformed( ActionEvent e ) {
        if(e.getSource() == view.checkAnswer){
            if(model.isRowFull){
                model.check();
            }
        }
    }

    public void mousePressed(MouseEvent e) {
        Point mouse = new Point();

        mouse = e.getPoint();
        if (model.isPlaying){
            if (mouse.x > 350) {
                int button = 1 + (int)((mouse.y - 32) / 50);
                if ((button >= 1) && (button <= 5)){
                    model.fillHole(button);
                    if(model.pinsRepaint){
                        view.repaintPins( model.pinsToRepaint );
                    }
                }
            }
        }
    }

    public void mouseClicked(MouseEvent e) {}
    public void mouseReleased(MouseEvent e){}
    public void mouseEntered(MouseEvent e) {}
    public void mouseExited(MouseEvent e)  {}
}

推荐答案

如您所见，Model–View–Controller 模式不是万能的，但它提供了一些优势.植根于 MVC，Swing 可分离模型架构在 Swing 架构概述.基于本大纲，以下示例显示了一个MVC 实现了一个更简单的游戏，说明了类似的原则.请注意，Model 管理随机选择的单个 Piece.为了响应用户的选择，View 调用 check() 方法，同时通过 update 监听来自 Model 的响应().View 然后使用从 Model 获得的信息进行自我更新.类似地，Controller 可以reset() Model.特别是 Model 中没有绘图，View 中没有游戏逻辑.这个有点复杂的游戏旨在说明相同的概念.

As you've discovered, the Model–View–Controller pattern is no panacea, but it offers some advantages. Rooted in MVC, the Swing separable model architecture is discussed in A Swing Architecture Overview. Based on this outline, the following example shows an MVC implementation of a much simpler game that illustrates similar principles. Note that the Model manages a single Piece, chosen at random. In response to a user's selection, the View invokes the check() method, while listening for a response from the Model via update(). The View then updates itself using information obtained from the Model. Similarly, the Controller may reset() the Model. In particular, there is no drawing in the Model and no game logic in the View. This somewhat more complex game was designed to illustrate the same concepts.

附录:我已经修改了原始示例以显示 MVC 允许一种在不改变 Model 的性质的情况下增强 View 的方法.

Addendum: I've modified the original example to show how MVC allows one to enhance the View without changing the nature of the Model.

附录:正如@a​​kf 所观察到的，MVC 取决于 观察者模式.您的 Model 需要一种方法来通知 View 更改.有几种方法被广泛使用:

Addendum: As @akf observes, MVC hinges on the observer pattern. Your Model needs a way to notify the View of changes. Several approaches are widely used:

  • 在下面的示例中，Model 扩展了 Observable 为简单起见.

  • In the example below, Model extends Observable for simplicity.

更常见的方法是使用 EventListenerList，如Converter 应用和大量EventListener 子接口和实现类.

A more common approach uses an EventListenerList, as shown in the Converter application and suggested by the large number of EventListener subinterfaces and implementing classes.

第三种选择是使用 PropertyChangeListener，如图这里和这里.

A third option is to use a PropertyChangeListener, as shown here and here.

附录:关于 Swing 控制器的一些常见问题已在此处和这里.

Addendum: Some common questions about Swing controllers are addressed here and here.

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Observable;
import java.util.Observer;
import java.util.Random;
import javax.swing.Icon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

/**
 * @see https://stackoverflow.com/q/3066590/230513
 * 15-Mar-2011 r8 https://stackoverflow.com/questions/5274962
 * 26-Mar-2013 r17 per comment
 */
public class MVCGame implements Runnable {

    public static void main(String[] args) {
        EventQueue.invokeLater(new MVCGame());
    }

    @Override
    public void run() {
        JFrame f = new JFrame();
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.add(new MainPanel());
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }
}

class MainPanel extends JPanel {

    public MainPanel() {
        super(new BorderLayout());
        Model model = new Model();
        View view = new View(model);
        Control control = new Control(model, view);
        JLabel label = new JLabel("Guess what color!", JLabel.CENTER);
        this.add(label, BorderLayout.NORTH);
        this.add(view, BorderLayout.CENTER);
        this.add(control, BorderLayout.SOUTH);
    }
}

/**
 * Control panel
 */
class Control extends JPanel {

    private Model model;
    private View view;
    private JButton reset = new JButton("Reset");

    public Control(Model model, View view) {
        this.model = model;
        this.view = view;
        this.add(reset);
        reset.addActionListener(new ButtonHandler());
    }

    private class ButtonHandler implements ActionListener {

        @Override
        public void actionPerformed(ActionEvent e) {
            String cmd = e.getActionCommand();
            if ("Reset".equals(cmd)) {
                model.reset();
            }
        }
    }
}

/**
 * View
 */
class View extends JPanel {

    private static final String s = "Click a button.";
    private Model model;
    private ColorIcon icon = new ColorIcon(80, Color.gray);
    private JLabel label = new JLabel(s, icon, JLabel.CENTER);

    public View(Model model) {
        super(new BorderLayout());
        this.model = model;
        label.setVerticalTextPosition(JLabel.BOTTOM);
        label.setHorizontalTextPosition(JLabel.CENTER);
        this.add(label, BorderLayout.CENTER);
        this.add(genButtonPanel(), BorderLayout.SOUTH);
        model.addObserver(new ModelObserver());
    }

    private JPanel genButtonPanel() {
        JPanel panel = new JPanel();
        for (Piece p : Piece.values()) {
            PieceButton pb = new PieceButton(p);
            pb.addActionListener(new ButtonHandler());
            panel.add(pb);
        }
        return panel;
    }

    private class ModelObserver implements Observer {

        @Override
        public void update(Observable o, Object arg) {
            if (arg == null) {
                label.setText(s);
                icon.color = Color.gray;
            } else {
                if ((Boolean) arg) {
                    label.setText("Win!");
                } else {
                    label.setText("Keep trying.");
                }
            }
        }
    }

    private class ButtonHandler implements ActionListener {

        @Override
        public void actionPerformed(ActionEvent e) {
            PieceButton pb = (PieceButton) e.getSource();
            icon.color = pb.piece.color;
            label.repaint();
            model.check(pb.piece);
        }
    }

    private static class PieceButton extends JButton {

        Piece piece;

        public PieceButton(Piece piece) {
            this.piece = piece;
            this.setIcon(new ColorIcon(16, piece.color));
        }
    }

    private static class ColorIcon implements Icon {

        private int size;
        private Color color;

        public ColorIcon(int size, Color color) {
            this.size = size;
            this.color = color;
        }

        @Override
        public void paintIcon(Component c, Graphics g, int x, int y) {
            Graphics2D g2d = (Graphics2D) g;
            g2d.setRenderingHint(
                RenderingHints.KEY_ANTIALIASING,
                RenderingHints.VALUE_ANTIALIAS_ON);
            g2d.setColor(color);
            g2d.fillOval(x, y, size, size);
        }

        @Override
        public int getIconWidth() {
            return size;
        }

        @Override
        public int getIconHeight() {
            return size;
        }
    }
}

/**
 * Model
 */
class Model extends Observable {

    private static final Random rnd = new Random();
    private static final Piece[] pieces = Piece.values();
    private Piece hidden = init();

    private Piece init() {
        return pieces[rnd.nextInt(pieces.length)];
    }

    public void reset() {
        hidden = init();
        setChanged();
        notifyObservers();
    }

    public void check(Piece guess) {
        setChanged();
        notifyObservers(guess.equals(hidden));
    }
}

enum Piece {

    Red(Color.red), Green(Color.green), Blue(Color.blue);
    public Color color;

    private Piece(Color color) {
        this.color = color;
    }
}

这篇关于重写为 MVC 后 GUI 无法正常工作的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持编程学习网！

本文标题为：重写为 MVC 后 GUI 无法正常工作

上一篇： 为什么 Spring MVC 以 404 响应并报告“No mapping found for HTTP request with URI [...] in DispatcherServlet"?
下一篇： Java 'for each' 循环是如何工作的?

基础教程推荐

学习HTML
学习jQuery
学习Laravel
学习CSS3
学习Vue.js
学习Bootstrap5
学习ThinkPHP
学习AJAX
猜你喜欢
最新文章
热门文章
编程基础
热门标签
网站首页 HTML/CSS 菜单 Layui Yii2