如何知道我触摸了网格 (10x10) 的哪个单元格？

Question

我正在使用 Canvas 和我使用 canvas.drawRect 绘制的 10x10 网格创建一个扫雷器。问题是，我不知道如何获取任何单元格的坐标（例如：在我的网格上的位置 (2,3) 中，物理坐标是什么？）。也许我没有正确地做网格？（我是初学者..）但是我必须使用Canvas，没有图形。我在这里看到了一些答案，但没有真正帮助我..

代码如下：

package com.example.meinsweeper_ja;

import java.util.Random;
import android.annotation.SuppressLint;
import android.content.*;
import android.graphics.*;
import android.util.*;
import android.view.*;

public class CustomView extends View {

private Paint black, grey, white, blue, green, yellow, red;
private Rect square, edge;
private boolean grid[][]; // true = uncovered false = covered
private boolean mines[][]; // true = mine false = no mine
private int arround[][]; // Nb of mine around
private float touchx[];
private float touchy[];
private int nb_mines, nb_ard;

public CustomView(Context c) {
    super(c);
    init();
}

public CustomView(Context c, AttributeSet as) {
    super(c, as);
    init();
}

public CustomView(Context c, AttributeSet as, int default_style) {
    super(c, as, default_style);
    init();
}

private void init() {
    black = new Paint(Paint.ANTI_ALIAS_FLAG);
    grey = new Paint(Paint.ANTI_ALIAS_FLAG);
    white = new Paint(Paint.ANTI_ALIAS_FLAG);
    yellow = new Paint(Paint.ANTI_ALIAS_FLAG);
    red = new Paint(Paint.ANTI_ALIAS_FLAG);
    green = new Paint(Paint.ANTI_ALIAS_FLAG);
    blue = new Paint(Paint.ANTI_ALIAS_FLAG);

    black.setColor(0xFF000000);
    grey.setColor(0xFF808080);
    white.setColor(0xFFFFFFFF);
    yellow.setColor(0xFFFFFF00);
    red.setColor(0xFFFF0000);
    green.setColor(0xFF00FF00);
    blue.setColor(0xFF0000FF);

    touchx = new float[10];
    touchy = new float[10];
    grid = new boolean[10][10];
    mines = new boolean[10][10];

    arround = new int[10][10];

    nb_mines = 20;

    square = new Rect(-24, -24, 24, 24);
    edge = new Rect(100, 100, 100, 100);

    reset();
}

private void reset() {
    for (int i = 0; i < 10; i++) {
        for (int j = 0; j < 10; j++) {
            grid[i][j] = false; // CLEAR THE BOARD
            if (nb_mines > 0) { // PLACE 20 MINES
                Random ping = new Random();
                if ((ping.nextInt(4) == 1)) {
                    mines[i][j] = true;
                    nb_mines--;
                }
            }
        }
    }

    for (int i = 0; i < 10; i++) { // CALCULATES NB OF MINES AROUND
        for (int j = 0; j < 10; j++) {
            if (!mines[i][j]) {
                nb_ard = 0;
                if (i == 0 && j == 0) { // TOP LEFT
                    if (mines[0][1])
                        nb_ard++;
                    if (mines[1][0])
                        nb_ard++;
                    if (mines[1][1])
                        nb_ard++;
                    arround[i][j] = nb_ard;
                } else if (i == 0 && j > 0 && j < 9) { // 1st Column
                    if (mines[0][j - 1])
                        nb_ard++;
                    if (mines[0][j + 1])
                        nb_ard++;
                    if (mines[1][j])
                        nb_ard++;
                    if (mines[1][j - 1])
                        nb_ard++;
                    if (mines[1][j + 1])
                        nb_ard++;
                    arround[i][j] = nb_ard;
                } else if (j == 0 && i < 9) { // 1st Row
                    if (mines[i - 1][0])
                        nb_ard++;
                    if (mines[i + 1][0])
                        nb_ard++;
                    if (mines[i][1])
                        nb_ard++;
                    if (mines[i - 1][1])
                        nb_ard++;
                    if (mines[i + 1][1])
                        nb_ard++;
                    arround[i][j] = nb_ard;
                } else if (i == 9 && j == 9) { // BOTTOM RIGHT
                    if (mines[8][8])
                        nb_ard++;
                    if (mines[8][9])
                        nb_ard++;
                    if (mines[9][8])
                        nb_ard++;
                    arround[i][j] = nb_ard;
                } else if (i == 9 && j < 9 && j > 0) { // Last Column
                    if (mines[9][j - 1])
                        nb_ard++;
                    if (mines[9][j + 1])
                        nb_ard++;
                    if (mines[8][j])
                        nb_ard++;
                    if (mines[8][j - 1])
                        nb_ard++;
                    if (mines[8][j + 1])
                        nb_ard++;
                    arround[i][j] = nb_ard;
                } else if (j == 9 && i < 9 && i > 0) { // Last Row
                    if (mines[i - 1][0])
                        nb_ard++;
                    if (mines[i + 1][0])
                        nb_ard++;
                    if (mines[i][8])
                        nb_ard++;
                    if (mines[i - 1][8])
                        nb_ard++;
                    if (mines[i + 1][8])
                        nb_ard++;
                    arround[i][j] = nb_ard;
                } else if (i == 0 && j == 9) { // BOTTOM LEFT
                    if (mines[0][8])
                        nb_ard++;
                    if (mines[1][9])
                        nb_ard++;
                    if (mines[1][8])
                        nb_ard++;
                    arround[i][j] = nb_ard;
                } else if (i == 9 && j == 0) { // TOP RIGHT
                    if (mines[9][1])
                        nb_ard++;
                    if (mines[8][0])
                        nb_ard++;
                    if (mines[8][1])
                        nb_ard++;
                    arround[i][j] = nb_ard;
                } else { // MIDDLE GRID
                    if (mines[i - 1][j - 1])
                        nb_ard++;
                    if (mines[i - 1][j])
                        nb_ard++;
                    if (mines[i - 1][j + 1])
                        nb_ard++;
                    if (mines[i][j - 1])
                        nb_ard++;
                    if (mines[i][j + 1])
                        nb_ard++;
                    if (mines[i + 1][j - 1])
                        nb_ard++;
                    if (mines[i + 1][j])
                        nb_ard++;
                    if (mines[i + 1][j + 1])
                        nb_ard++;
                    arround[i][j] = nb_ard;
                }
            }
        }
    }

}

@Override
public void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    for (int i = 0; i < 10; i++) {
        for (int j = 0; j < 10; j++) {
            touchy[j] = 50.f;
            canvas.save();
            if (i == 0 && j == 0)
                canvas.translate(200.f, touchy[j]);
            else
                canvas.translate(touchx[i], touchy[j]);
            canvas.drawRect(edge, white);

            if (!grid[i][j])
                canvas.drawRect(square, black);
            else {
                if (arround[i][j] == 1) {
                    canvas.drawRect(square, grey);
                    canvas.drawText(Integer.toString(1), i, j, blue);
                } else if (arround[i][j] == 2) {
                    canvas.drawRect(square, grey);
                    canvas.drawText(Integer.toString(2), i, j, green);
                } else if (arround[i][j] == 3) {
                    canvas.drawRect(square, grey);
                    canvas.drawText(Integer.toString(3), i, j, yellow);
                } else if (arround[i][j] > 3) {
                    canvas.drawRect(square, grey);
                    canvas.drawText(Integer.toString(arround[i][j]), i, j,
                            red);
                } else if (mines[i][j]) {
                    canvas.drawRect(square, red);
                    canvas.drawText("M", i, j, black);
                } else if (arround[i][j] == 0)
                    canvas.drawRect(square, grey);
            }
        }
        touchx[i] += 50.f;
        canvas.translate(touchx[i], -10 * touchx[i]);
    }
}

@SuppressLint("ClickableViewAccessibility")
@Override
public boolean onTouchEvent(MotionEvent event) {
    if (event.getActionMasked() == MotionEvent.ACTION_DOWN) {
        int pidX = (int) event.getX();
        int pidY = (int) event.getY();
        for (int i = 0; i < 10; i++) {
            for (int j = 0; j < 10; j++) {
                if (touchx[i] == pidX && touchy[j] == pidY) {
                    if (mines[i][j]) {
                        reset();
                    }
                }
            }
        }
        invalidate();
        return true;
    }
    return super.onTouchEvent(event);
}
}

问题肯定出在 onDraw() 方法中，但正如我之前所说，我真的不知道如何以更好的方式绘制网格。希望您能理解我的问题。

我知道我有很多方法，当我找到解决问题的办法时我会解决这个问题。

提前致谢！

Answer 1

所以您可以考虑重构您的代码...

创建一个类似 "Tile" 的对象，而不是拥有不同的对象。它可能看起来像： public 枚举 DrawState { 普通的，安全的，爆炸了； } public class 绘画 { public static Paint 正常，安全，爆炸；静态的 { NORMAL = new Paint(); NORMAL.setColor(...) 设置样式(...) // ETC } // 这些甚至可以是 DrawState 的成员，只需将它们传递到 // 构造函数然后你可以像 DrawState.Exploded.getPaint(); } public class 瓷砖 { 私有最终 int id；私有矩形边界矩形；私人布尔 hasMine；私有 DrawState 绘制状态； public Tile(int theId, Rect theBoundingRect, boolean mined) { id = theId; boundingRect = theBoundingRect; hasMine = 已开采； drawState = DrawState.Normal; } public boolean containsTouch(int x, int y) { return boundingRect.contains(x, y); } public void draw(Canvas c) { 切换（状态）{ 情况正常： c.drawRect(boundingRect, Paints.NORMAL); return; 案例安全： c.drawRect(boundingRect, Paints.SAFE); return; 案例爆炸： c.drawRect(boundingRect, Paints.EXPLODED); } } public void setInspected() { drawState = DrawState.SAFE; } public boolean isMined() { return hasMine; } public int getId() { return id; } // ETC }

现在在您的自定义字段视图中，您可以执行以下操作：

@Override public boolean onTouch(MotionEvent event) { for (Tile t : tiles) { if (t.containsTouch(event.getX(), event.getY())) { if (t.isMined()) { reset(); } else { t.setInspected(); } invalidate(); } } }

这让事情变得简单多了。当然，您必须初始化您的图块列表，您可以通过计算每个矩形的左、上、右、底并将 new Rect(l, t, r, b) 传递到图块构造函数中来实现。然后它可以很容易地获得 id，或数组位置，以及很多其他的东西......

当然，如果你想把id做成一个元组，你可以只用取模运算符；如果您知道您的图块将保留在列表中的初始索引位置，您甚至不需要保存 id。同样，您也可以在初始化图块时传入 i 和 j 而不是 id。

希望对您有所帮助！

编辑进一步解释：

所以现在由于每个图块都有足够的信息来照顾自己，它可以有一个绘制函数，例如：
public void draw(Canvas c) { c.drawRect(boundingRect, drawState.getPaint()); // assuming the paint is set to Style.FILL it'll fill the // rect with t/l/b/r as was set during construction // if you had a flag image, you could draw it on top of the boundingRect // int t = boundingRect.centerX() - (flagImage.getIntrisnicWidth()/2); // int l = boundingRect.centerY() - (flagImage.getIntrisnicHeight()/2); // c.drawBitmap(flagImage, bitmapTop, bitmapLeft, null); }

现在从您的自定义网格视图 class： @Override public void onDraw(Canvas c) { // draw other things for (Tile t : tiles) { t.draw(c); } // draw other things }

记住先绘制的会被覆盖，所以如果你这样做： canvas.drawRect(rect1); canvas.drawRect(rect2); rect2 与 rect1 位于同一位置，它将绘制在 rect1 之上。

如何知道我触摸了网格 (10x10) 的哪个单元格？

How to know which cell of a grid (10x10) I've touched?

java

grid

canvas

view

minesweeper