计数器：计数在1到300之间

Question

我有一个计数器，我希望计算在1到300之间。我使用一个最终变量，我从另一个类的计数器中获取，然后打破该数字并在屏幕上显示正确的数字（以三张图片 - 一张，几张，几百张）。但是，我很难让它正确计算。每次用户点击某个区域时，我都希望计数器相应地更新。以下是我正在使用的两个类：

    public class Counter {

int count = 0;

public int IncreaseOnes() {

    if (count >= 0 && count < 300){
        count = count++;
        }   
    else {
        count = 0;
    }
        return count;
}

public int DecreaseOnes() {

    if (count >= 0 && count < 300){
        count = count--;
        }   
    else {
        count = 0;
    }
        return count;
}

public int IncreaseTens() {

if (count >= 0 && count < 300){
    count = count + 10;
    }   
else {
    count = 0;
}
    return count;
 }
 public int DecreaseTens() {

    if (count >= 0 && count < 300){
        count = count - 10;
        }   
    else {
        count = 0;
    }
        return count;
}

public int IncreaseHundreds() {

    if (count >= 0 && count < 300){
        count = count + 100;
        }   
    else {
        count = 0;
    }
        return count;
}

public int DecreaseHundreds() {

    if (count >= 0 && count < 300){
        count = count - 100;
        }   
    else {
        count = 0;
    }
        return count;
}

public int getFinalCount() {
    System.out.println(count);
    return count;       
}

}  

然后

public class TempoScreen extends Screen {
public TempoScreen(Game game) {
    super(game);
}

Counter counter = new Counter();
private final int number_y = 240;
private final int number_hundreds_x = 75;
private final int number_tens_x = 195;
private final int number_ones_x = 308;

@Override
public void update(float deltaTime) {

    List<TouchEvent> touchEvents = game.getInput().getTouchEvents();

    int len = touchEvents.size();
    for (int i = 0; i < len; i++) {
        TouchEvent event = touchEvents.get(i);
        if (event.type == TouchEvent.TOUCH_UP) {

            if (inBounds(event, 75,138,145,205)) {
                //Increase Tempo
                //Upper Button Left
                counter.IncreaseHundreds();

                } 
            } if (inBounds (event, 201,141,269,205)) {
                //Increase Tempo
                //Upper Button Middle
                counter.IncreaseTens();

            } if (inBounds (event, 318,143,385,203)) {
                //Increase Tempo
                //Upper Button Right
                counter.IncreaseOnes();

            } if (inBounds (event, 75,435,142,498)) {
                //Decrease Tempo
                //Lower Button Left
                counter.DecreaseHundreds();

            } if (inBounds (event, 199,437,268,499)) {
                //Decrease Tempo
                //Lower Button Middle
                counter.DecreaseTens();

            } if (inBounds (event, 319,435,382,497)) {
                //Decrease Tempo
                //Lower Button Right
                counter.DecreaseOnes();

            } if (inBounds(event, 4,662,143,794)) {
                //GO BACK TO MAINMENU
                game.setScreen(new MainMenuScreen (game));
                // TO SAVE WHICH ONE IT USE USE FILE IO CLASSES
            } if (inBounds (event, 341,665,477,794)) {
                //GO TO GAME
                game.setScreen(new GameScreen (game));

            }


        } 
    }


private boolean inBounds(TouchEvent event, int x, int y, int width,
                         int height) {
    if (event.x > x && event.x < x + width - 1 && event.y > y
            && event.y < y + height - 1)
        return true;
    else
        return false;
}


@Override
public void paint(float deltaTime) {
    Graphics g = game.getGraphics();
    int finalCount = counter.getFinalCount();

    g.drawImage(Assets.tempo, 0, 0);
    g.drawImage(Assets.zero, number_hundreds_x, number_y); //draw 0 hundreds
    g.drawImage(Assets.zero, number_tens_x, number_y); //draw 0 tens
    g.drawImage(Assets.zero, number_ones_x, number_y); //draw 0 ones

    int ones = finalCount % 10;
    int tens = finalCount / 10 % 10;
    int hundreds = finalCount / 100 % 10;

    if (ones == 2) {
        g.drawImage(Assets.two, number_ones_x, number_y);
    } 

    if (ones == 3) {
        g.drawImage(Assets.three, number_ones_x, number_y);
    } 

    if (ones == 4) {
        g.drawImage(Assets.four, number_ones_x, number_y);
    } 

    if (ones == 5) {
        g.drawImage(Assets.five, number_ones_x, number_y);
    }

    if (ones == 6) {
        g.drawImage(Assets.six, number_ones_x, number_y);
    } 

    if (ones == 7) {
        g.drawImage(Assets.seven, number_ones_x, number_y);
    } 

    if (ones == 8) {
        g.drawImage(Assets.eight, number_ones_x, number_y);
    } 

    if (ones == 9) {
        g.drawImage(Assets.nine, number_ones_x, number_y); 
    }

    if (tens == 1 && ones == 0) {
        g.drawImage(Assets.one, number_tens_x, number_y);
        g.drawImage(Assets.zero, number_ones_x, number_y);
    }

    if (tens == 2 && ones == 0) {
        g.drawImage(Assets.two, number_tens_x, number_y);
        g.drawImage(Assets.zero, number_ones_x, number_y);
    }

    if (tens == 3 && ones == 0) {
        g.drawImage(Assets.three, number_tens_x, number_y);
        g.drawImage(Assets.zero, number_ones_x, number_y);
    }

    if (tens == 4 && ones == 0) {
        g.drawImage(Assets.four, number_tens_x, number_y);
        g.drawImage(Assets.zero, number_ones_x, number_y);
    }

    if (tens == 5 && ones == 0) {
        g.drawImage(Assets.five, number_tens_x, number_y);
        g.drawImage(Assets.zero, number_ones_x, number_y);
    }

    if (tens == 6 && ones == 0) {
        g.drawImage(Assets.six, number_tens_x, number_y);
        g.drawImage(Assets.zero, number_ones_x, number_y);
    }

    if (tens == 7 && ones == 0) {
        g.drawImage(Assets.seven, number_tens_x, number_y);
        g.drawImage(Assets.zero, number_ones_x, number_y);
    }

    if (tens == 8 && ones == 0) {
        g.drawImage(Assets.eight, number_tens_x, number_y);
        g.drawImage(Assets.zero, number_ones_x, number_y);
    }

    if (tens == 9 && ones == 0) {
        g.drawImage(Assets.nine, number_tens_x, number_y);
        g.drawImage(Assets.zero, number_ones_x, number_y);
    }

    if (tens == 1) {
        g.drawImage(Assets.one, number_tens_x, number_y);
    }

    if (tens == 2) {
        g.drawImage(Assets.two, number_tens_x, number_y);
    } 

    if (tens == 3) {
        g.drawImage(Assets.three, number_tens_x, number_y);
    } 

    if (tens == 4) {
        g.drawImage(Assets.four, number_tens_x, number_y);
    } 

    if (tens == 5) {
        g.drawImage(Assets.five, number_tens_x, number_y);
    } 

    if (tens == 6) {
        g.drawImage(Assets.six, number_tens_x, number_y);
    } 

    if (tens == 7) {
        g.drawImage(Assets.seven, number_tens_x, number_y);
    } 

    if (tens == 8) {
        g.drawImage(Assets.eight, number_tens_x, number_y);
    } 

    if (tens == 9) {
        g.drawImage(Assets.nine, number_tens_x, number_y);
    } 

    if (hundreds == 1) {
        g.drawImage(Assets.one, number_hundreds_x, number_y);
    }

    if (hundreds == 2) {
        g.drawImage(Assets.two, number_hundreds_x, number_y);
    } 

    if (hundreds == 3) {
        g.drawImage(Assets.three, number_hundreds_x, number_y);
    } 

}

那么如何让我的计数器正确计数？而且，有没有更好的方法来格式化我的代码，所以我不会使用尽可能多的if语句？谢谢！

以下是屏幕的样子：

Answer 1

更改

public int IncreaseOnes() {
    ...
    count = count++;
    ...
}

public int DecreaseOnes() {
    ...
    count = count--;
    ...
}

到

public int IncreaseOnes() {
    ...
    count++;
    ...
}

public int DecreaseOnes() {
    ...
    count--;
    ...
}

检查this，了解 post-pre 增量＆amp; amp;减少运营商。

Answer 2

尝试以下代码。我试图减少那里的代码量。

您还需要线程安全的Counter类。

专柜课：

import java.util.Scanner;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.locks.ReentrantLock;

public class Counter {

    private static final int MAX_COUNT = 299;
    /*Just to be safe*/
    private AtomicInteger counter = new AtomicInteger();
    private ReentrantLock stepLock = new ReentrantLock();

    public void step(int stepValue) {
        stepLock.lock();
        try {
            int steppedValue = counter.get() + stepValue;
            if(steppedValue < 0 || steppedValue > MAX_COUNT) {
                /*reset counter*/
                counter.set(0);
            } else {
                counter.set(steppedValue);
            }
        } finally {
            stepLock.unlock();
        }
    }

    public int getFinalCount() {
        System.out.println(counter.get());
        return counter.get();
    }

}

TempoScreen类：

public class TempoScreen extends Screen {
    Dimension[][] updownDims = new Dimension[2][3];
    Dimension mainMenuDim;
    Dimension gameMenuDim;

    //I wasn't sure what the asset types were, replace Object[] wity assetType[]
    Object[] assets = [Assets.zero, Azzets.one,Azzets.two,Azzets.three,Azzets.four,Azzets.five,Azzets.six,Azzets.seven,Azzets.eight,Azzets.nine];

    Counter counter = new Counter();
    private final int number_y = 240;
    private final int number_hundreds_x = 75;
    private final int number_tens_x = 195;
    private final int number_ones_x = 308;

    private final int[] number_xs = {number_ones_x, number_tens_x, number_hundreds_x};

    public TempoScreen(Game game) {
        super(game);
        //up buttons
        updownDims[0][0] = new Dimension(318,143,385,203);//+1
        updownDims[0][1] = new Dimension(201,141,269,205);//+10
        updownDims[0][2] = new Dimension(75,138,145,205);//+100

        //down buttons
        updownDims[1][0] = new Dimension(319,435,382,497);//-1
        updownDims[1][1] = new Dimension(199,437,268,499);//-10
        updownDims[1][2] = new Dimension(75,435,142,498);//-100

        mainMenuDim = new Dimension(4,662,143,794);
        gameMenuDim = new Dimension(341,665,477,794);

    }

    public class Dimension {
        private int x;
        private int y;
        private int width;
        private int height;

        public Dimension(int x, int y, int width, int height) {
            super();
            this.x = x;
            this.y = y;
            this.width = width;
            this.height = height;
        }

        public boolean contains (int x, int y) {
            boolean isInside = false;
            if (x > this.x && x < (this.x + width - 1) && y > this.y
                    && y < (this.y + height - 1)) {
                isInside = true;
            }

            return isInside;
        }
    }

    @Override
    public void update(float deltaTime) {

        List<TouchEvent> touchEvents = game.getInput().getTouchEvents();

        int len = touchEvents.size();
        for (TouchEvent event : touchEvents) {
            if (event.type != TouchEvent.TOUCH_UP) {
                continue;
            }

            int x = event.x;
            int y = event.y;

            boolean inUpdowndims = false;
            for(int row = 0; row < updownDims.length; row++) {
                for(int col = 0; col < updownDims[0].length; col++) {
                    if(inUpdowndims = updownDims[row][col].contains(x, y)) {
                        int stepValue = (int)Math.pow(10, col);
                        counter.step(row == 0 ? stepValue : -stepValue);
                    }
                }
            }

            if(!inUpdowndims) {
                if(mainMenuDim.contains(x, y) {
                    game.setScreen(new MainMenuScreen(game))
                } else if(gameMenuDim.contains(x, y)) {
                    game.setScreen(new GameScreen(game));
                }
            }
        }
    }

    @Override
    public void paint(float deltaTime) {
        Graphics g = game.getGraphics();
        int finalCount = counter.getFinalCount();

        g.drawImage(Assets.tempo, 0, 0);

        //one loop is enough for all the images
        for(int xi = 0; xi < number_xs.length; xi++) {
            int num = finalCount % 10;
            finalCount /= 10;

            g.drawImage(assets[num], number_xs[xi], number_y);
        }
    }
}

Answer 3

使类计数器的每个方法同步如

public syncronized int IncreaseOnes(){
}

Answer 4

public class Counter {

    private int count = 0;

    public int increaseOnes(){
        return increase(1);
    }

    public int decreaseOnes(){
        return increase(-1);
    }

    public int increaseTens(){
        return increase(10);
    }

    public int decreaseTens(){
        return increase(-10);
    }    

    public int increaseHundreds(){
        return increase(100);
    }

    public int decreaseHundreds(){
        increase(-10);
    }    

    private int increase(int delta){
        count+=delta;
        if (count < 0 || count > 300){
            count = 0;
        }
        return count;
    }
}

对于paint方法，请考虑使用开关结构。

switch (ones){
    case 1:
        g.drawImage(Assets.one, number_ones_x, number_y);
        break;
    case 2:
        g.drawImage(Assets.two, number_ones_x, number_y);
        break;
    ...
    default: //Is 0
        g.drawImage(Assets.two, number_ones_x, number_y);
        //Invoke an internal Method doing the same but for tens
}