java - 当我的程序运行时，无法更改timer.scheduleAtFixedRate(TimerTask任务，长延迟，长周期)的长周期

Question

我正在制作约翰·康威的生命游戏，但我无法弄清楚如何更改代码中的时间段或在本例中的时间长度 time.scheduleAtFixedRate(task, 0, timelength)程序正在运行。我试图在代码中使用 jslider 更改时间长度，但它根本没有改变。在代码中，一些代码创建了可以忽略的图形，而其他许多代码则用于 jtextfields 和 jbutton 等内容。

//Game of Life
package ics_sad_majorproject.gameoflifejava_1;
import java.util.Timer;
import java.util.TimerTask;
import java.awt.Image;
import java.awt.Graphics;
import java.awt.Color;
import javax.swing.SwingUtilities;

public class GameOfLife extends javax.swing.JFrame {
    int intperiod = 100;
    int wid = 50, hei = 50;
    boolean[][] currentMove = new boolean[hei][wid], nextMove = new boolean[hei][wid];
    boolean play;
    public static int intpopulation = 0;
   Image offScrImg;
   Graphics offScrGraph;
  public static int intGeneration = 0;
  Timer time = new Timer();

   public GameOfLife() {
        initComponents();
        offScrImg = createImage(jPanel2.getWidth(), jPanel2.getHeight());
        offScrGraph = offScrImg.getGraphics();
        TimerTask task = new TimerTask(){
          public void run() {
              if(play == true){
                  intGeneration++;
               jLabel6.setText( "Generation: " + intGeneration );
              for(int i = 0; i < hei; i++){
                  for(int j = 0; j < wid; j++){
                      nextMove[i][j] = decide(i,j);
                  }   
                  }
               for(int i = 0; i < hei; i++){
                  for (int j = 0; j < wid; j++){
                  currentMove[i][j] = nextMove[i][j];
                  }   
                  }
               repain();
                  }
          }
            };
        time.scheduleAtFixedRate(task, 0, intperiod);
        repain();
    }

private boolean decide(int i, int j){
    int neighbors = 0; 
    if(j > 0){
        if(currentMove[i][j-1]) neighbors++;
        if(i>0) if(currentMove[i-1][j-1]) neighbors++;
        if(i<hei-1) if(currentMove[i+1][j-1]) neighbors++;
    }
    if(j < wid - 1){
        if(currentMove[i][j+1]) neighbors++;
        if(i>0) if(currentMove[i-1][j+1]) neighbors++;
        if(i<hei-1) if(currentMove[i+1][j+1]) neighbors++;
    }
     if(i>0) if(currentMove[i-1][j]) neighbors++;
     if(i<hei-1) if(currentMove[i+1][j]) neighbors++;
     if(currentMove[i][j]&& neighbors < 2)intpopulation--;
     if(currentMove[i][j]&& neighbors > 3)intpopulation--;
     if(currentMove[i][j] && neighbors == 3)intpopulation--;
     if(neighbors == 3) intpopulation++;
  jLabel5.setText("Population: " + Integer.toString(intpopulation));
     if(neighbors == 3) return true;
     if(currentMove[i][j] && neighbors == 2)return true;
     return false;
     }

    private void repain(){
        offScrGraph.setColor(Color.BLACK);
        offScrGraph.fillRect(0, 0, jPanel2.getWidth(), jPanel2.getHeight());
        for (int i = 0; i < hei; i++){
            for (int j = 0; j < wid; j++){
                if(currentMove[i][j])
                {
                    offScrGraph.setColor(Color.getHSBColor((float) Math.random(), .8f, .8f));
                int x  = j * jPanel2.getWidth()/wid;
                int y = i * jPanel2.getHeight()/hei;
             offScrGraph.fillRect(x, y, jPanel2.getWidth()/wid, jPanel2.getHeight()/hei);
                 }
        }
        }
        offScrGraph.setColor(Color.BLACK);
        for (int i = 1; i < hei; i++){
            int y = i * jPanel2.getHeight()/hei;
            offScrGraph.drawLine(0, y, jPanel2.getWidth(), y);
        }
        for (int j = 1; j < wid; j++){
            int x  = j * jPanel2.getWidth()/wid;
            offScrGraph.drawLine(x, 0, x, jPanel2.getHeight());
        }
         jPanel2.getGraphics().drawImage(offScrImg, 0, 0, jPanel2);
    }
 private void jSlider1StateChanged(javax.swing.event.ChangeEvent evt) {                                      
         jLabel4.setText(Integer.toString(jSlider1.getValue()) + " milisecounds");
         intperiod = jSlider1.getValue(); 
    }      


private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {                                         
            currentMove = new boolean[hei][wid];
            intGeneration = 0;
            intpopulation = 0;
             jLabel6.setText( "Generation: " + intGeneration );
             jLabel5.setText( "population: " + intpopulation );
            repain();
        }                                        
         private void jPanel2MouseClicked(java.awt.event.MouseEvent evt) {                                     
            int j = wid * evt.getX() / jPanel2.getWidth();
            int i = hei * evt.getY() / jPanel2.getHeight();
            currentMove[i][j] = true;
            intpopulation++;
            jLabel5.setText("Population: " + Integer.toString(intpopulation));
            repain();
        }                                    

        private void jPanel2ComponentResized(java.awt.event.ComponentEvent evt) {                                         
            offScrImg = createImage(jPanel2.getWidth(), jPanel2.getHeight());
            offScrGraph = offScrImg.getGraphics();
            repain();
        }                                        

        private void jPanel2MouseDragged(java.awt.event.MouseEvent evt) {                                     
            int j = wid * evt.getX() / jPanel2.getWidth();
            int i = hei * evt.getY() / jPanel2.getHeight();
            if(SwingUtilities.isLeftMouseButton(evt)){
            currentMove[i][j] = true;
            intpopulation++;
            }else currentMove[i][j] = false;
        }                                    

        private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {                                         
            play = !play;
            if(play) jButton3.setText("Pause");
            else jButton3.setText("play");
            repain();
        }                                        

        private void jTextField4ActionPerformed(java.awt.event.ActionEvent evt) {                                            
           String text = jTextField4.getText();
                hei = Integer.valueOf(text);
               jTextField4.setText("Height: "+ Integer.toString(hei));
                currentMove = new boolean[hei][wid];
                nextMove = new boolean[hei][wid];
                repain();
        }                                           

        private void jTextField1ActionPerformed(java.awt.event.ActionEvent evt) {                                            
                String text = jTextField1.getText();
                wid = Integer.valueOf(text);
                jTextField1.setText( "Width: "+ Integer.toString(wid));
                currentMove = new boolean[hei][wid];
                nextMove = new boolean[hei][wid];
                repain();
        }             
    }

Answer 1

问题是，计时器一旦实例化并启动，就不会在运行时检查参数是否已更改。这是一种封闭。

每次更改其中一个参数时，都必须使用新参数创建一个新的计时器实例。

EDIT

import java.awt.*;
import javax.swing.SwingUtilities;
import java.util.Timer;
import java.util.TimerTask;

public class GameOfLife extends javax.swing.JFrame {

    // Put this parameters global in order to be able to change it from different points in your code
    Timer timer;
    TimerTask timerTask;
    int delay = 0;
    int period = 100;


    int wid = 200, hei = 100;
    boolean[][] currentMove = new boolean[hei][wid], nextMove = new boolean[hei]
            [wid];
    boolean play;
    public static int intpopulation = 0;
    Image offScrImg;
    Graphics offScrGraph;
    public static int intGeneration = 0;

    public GameOfLife() {
        initComponents();
        offScrImg = createImage(jPanel2.getWidth(), jPanel2.getHeight());
        offScrGraph = offScrImg.getGraphics();

        // start the very first timer instance
        restartTimer();

        repain();
    }

    /**
     * This method first checks, whether the timer is already instatiated.
     * If so, the current timer gets cancelled.
     * Then the timerTask gets recreated.
     *
     * Finally a new timer is instantiated and gets scheduled.
     */
    private void restartTimer() {
        if(timer != null) {
            timer.cancel();
        }

        resetTimerTask();

        System.out.println("TimerTask: " + (timerTask != null));
        System.out.println("period: " + period);
        System.out.println("delay: " + delay);

        timer = new Timer();
        timer.scheduleAtFixedRate(timerTask, delay, period);
    }

    private void resetTimerTask() {
        timerTask = new TimerTask(){
            public void run() {
                if(play == true){
                    intGeneration++;
                    for(int i = 0; i < hei; i++){
                        for(int j = 0; j < wid; j++){
                            nextMove[i][j] = decide(i,j);
                        }
                    }

                    for(int i = 0; i < hei; i++){
                        for (int j = 0; j < wid; j++){
                            currentMove[i][j] = nextMove[i][j];
                        }
                    }
                    repain();
                }
            }
        };
    }

    private void jSlider1StateChanged(javax.swing.event.ChangeEvent evt)      {
        jLabel4.setText(Integer.toString(jSlider1.getValue()));
        period = jSlider1.getValue();

        // whenever you change the period, start a new timer instance
        restartTimer();
    }

    private boolean decide(int i, int j){
        int neighbors = 0;
        if(j > 0){
            if(currentMove[i][j-1]) neighbors++;
            if(i>0) if(currentMove[i-1][j-1]) neighbors++;
            if(i<hei-1) if(currentMove[i+1][j-1]) neighbors++;
        }
        if(j < wid - 1){
            if(currentMove[i][j+1]) neighbors++;
            if(i>0) if(currentMove[i-1][j+1]) neighbors++;
            if(i<hei-1) if(currentMove[i+1][j+1]) neighbors++;
        }
        if(i>0) if(currentMove[i-1][j]) neighbors++;
        if(i<hei-1) if(currentMove[i+1][j]) neighbors++;
        if(currentMove[i][j]&& neighbors < 2)intpopulation--;
        if(currentMove[i][j]&& neighbors > 3)intpopulation--;
        if(currentMove[i][j] && neighbors == 3)intpopulation--;
        if(neighbors == 3) intpopulation++;
        jLabel5.setText("Population: " + Integer.toString(intpopulation));
        if(neighbors == 3) return true;
        if(currentMove[i][j] && neighbors == 2)return true;
        return false;
    }

    private void repain(){
        offScrGraph.setColor(Color.BLACK);
        offScrGraph.fillRect(0, 0, jPanel2.getWidth(), jPanel2.getHeight());
        for (int i = 0; i < hei; i++){
            for (int j = 0; j < wid; j++){
                if(currentMove[i][j])
                {
                    offScrGraph.setColor(Color.getHSBColor((float) Math.random(), .8f, .8f));
                    int x  = j * jPanel2.getWidth()/wid;
                    int y = i * jPanel2.getHeight()/hei;
                    offScrGraph.fillRect(x, y, jPanel2.getWidth()/wid, jPanel2.getHeight()/hei);
                }
            }
        }
        offScrGraph.setColor(Color.BLACK);
        for (int i = 1; i < hei; i++){
            int y = i * jPanel2.getHeight()/hei;
            offScrGraph.drawLine(0, y, jPanel2.getWidth(), y);
        }
        for (int j = 1; j < wid; j++){
            int x  = j * jPanel2.getWidth()/wid;
            offScrGraph.drawLine(x, 0, x, jPanel2.getHeight());
        }
        jPanel2.getGraphics().drawImage(offScrImg, 0, 0, jPanel2);
    }

    private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {
        currentMove = new boolean[hei][wid];
        intGeneration = 0;
        intpopulation = 0;
        jLabel6.setText( "Generation: " + intGeneration );
        jLabel5.setText( "population: " + intpopulation );
        repain();
    }
    private void jPanel2MouseClicked(java.awt.event.MouseEvent evt) {
        int j = wid * evt.getX() / jPanel2.getWidth();
        int i = hei * evt.getY() / jPanel2.getHeight();
        currentMove[i][j] = true;
        intpopulation++;
        jLabel5.setText("Population: " + Integer.toString(intpopulation));
        repain();
    }

    private void jPanel2ComponentResized(java.awt.event.ComponentEvent evt) {
        offScrImg = createImage(jPanel2.getWidth(), jPanel2.getHeight());
        offScrGraph = offScrImg.getGraphics();
        repain();
    }

    private void jPanel2MouseDragged(java.awt.event.MouseEvent evt) {
        int j = wid * evt.getX() / jPanel2.getWidth();
        int i = hei * evt.getY() / jPanel2.getHeight();
        if(SwingUtilities.isLeftMouseButton(evt)){
            currentMove[i][j] = true;
            intpopulation++;
        }else currentMove[i][j] = false;
    }

    private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {
        play = !play;
        if(play) jButton3.setText("Pause");
        else jButton3.setText("play");
        repain();
    }

    private void jTextField4ActionPerformed(java.awt.event.ActionEvent evt) {
        String text = jTextField4.getText();
        hei = Integer.valueOf(text);
        jTextField4.setText("Height: "+ Integer.toString(hei));
        currentMove = new boolean[hei][wid];
        nextMove = new boolean[hei][wid];
        repain();
    }

    private void jTextField1ActionPerformed(java.awt.event.ActionEvent evt) {
        String text = jTextField1.getText();
        wid = Integer.valueOf(text);
        jTextField1.setText( "Width: "+ Integer.toString(wid));
        currentMove = new boolean[hei][wid];
        nextMove = new boolean[hei][wid];
        repain();
    }
}