java - 在Android中绘制动态自定义 View 棋盘

Question

我想使用canvas和通过覆盖方法onDraw在android studio中动态绘制一个8×8的棋盘，我几乎已经成功了，但我遇到了一个非常烦人的问题。

我已经制作了一个自定义 View ，我的目标是使父布局与其子自定义 View 的大小相匹配，这样我的棋盘就可以覆盖整个屏幕。 (在 XML 文件中，父级和子级都设置为 match_parent)

我希望棋盘也覆盖屏幕的整个高度。

检查下面的图片这是我得到的结果，注意下部区域的巨大间隙，我的目的是垂直拉伸(stretch)棋盘并使其覆盖整个屏幕以消除该间隙。

这是我到目前为止所写的内容，但它没有达到我想要的效果: 棋盘类:

   public class ChessBoard extends View {
   private static final String TAG = ChessBoard.class.getSimpleName();

   private Rect rect;
   private static final int COLS = 8;
   private static final int ROWS = 8;

   Tile tile;
   private final  Tile[][] mTiles;
   private int x0 = 0;
   private int y0 = 0;
   private static final int DEF_SQUARE_SIZE=50;
   private int squareSize=0;
   private boolean flipped = false;

    public ChessBoard(final Context context,AttributeSet attrs) {

         super(context,attrs);
        this.mTiles = new Tile[COLS][ROWS];
        buildTiles();
        rect=new Rect();
      }

onDraw方法:

     protected void onDraw(final Canvas canvas) 
      {
         int width = getWidth();

         int height = getHeight();
         squareSize=Math.min(getSquareSizeWidth(width),getSquareSizeHeight(height));
         computeOrigins(width,height);

         for (int c = 0; c < COLS; c++) {
         for (int r = 0; r < ROWS; r++) {
            final int xCoord = getXCoord(c);
            final int yCoord = getYCoord(r);

            mTiles[c][r].setTileRect(rect);

            rect.left=xCoord;
            rect.top=yCoord;
            rect.right= rect.left+squareSize;  // right
            rect.bottom=rect.top + squareSize;
            mTiles[c][r].draw(canvas);

            }
             }

类图 block :

   public final class Tile {

      private static final String TAG = Tile.class.getSimpleName();
      private final int col;
      private final int row;

      private final Paint squareColor;
      private Rect tileRect;

    public Tile(final int col, final int row) {

      this.col = col;
      this.row = row;
      this.squareColor = new Paint();

    squareColor.setColor(isDark() ? Color.BLACK : Color.WHITE);
    squareColor.setAntiAlias(true);
}

public void draw(final Canvas canvas) {
    canvas.drawRect(tileRect, squareColor);
}

public String getColumnString() {
    switch (col) {
        case 0: return "A";
        case 1: return "B";
        case 2: return "C";
        case 3: return "D";
        case 4: return "E";
        case 5: return "F";
        case 6: return "G";
        case 7: return "H";
        default: return null;
    }
}

public String getRowString() {
    // To get the actual row, add 1 since 'row' is 0 indexed.
    return String.valueOf(row + 1);
}

public void handleTouch() {
    Log.d(TAG, "handleTouch(): col: " + col);
    Log.d(TAG, "handleTouch(): row: " + row);
    }

public boolean isDark() {
    return (col + row) % 2 == 0;
    }

public boolean isTouched(final int x, final int y) {
    return tileRect.contains(x, y);
}

public void setTileRect(final Rect tileRect) {
    this.tileRect = tileRect;
}

public String toString() {
    final String column = getColumnString();
    final String row    = getRowString();
    return "<Tile " + column + row + ">";
}

}
onMeasure方法:

       protected void onMeasure(int widthMeasureSpec, int  
       heightMeasureSpec)         
       {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);

        int width = getMeasuredWidth();
        int height = getMeasuredHeight();
        int parentWidth = MeasureSpec.getSize(widthMeasureSpec);

    int parentHeight = MeasureSpec.getSize(heightMeasureSpec);
    int sqSizeW = getSquareSizeWidth(width);
    int sqSizeH = getSquareSizeHeight(height);
    int sqSize = Math.min(sqSizeW, sqSizeH);

      if (height > width) {
        int p = getMaxHeightPercentage();
        height = Math.min(getHeight(sqSize), height * p / 100);
    } else {
        width = Math.min(getWidth(sqSize), width * 65 / 100);

    }
        setMeasuredDimension(width, height);
    }

类 ChessBoard 方法:

         protected int getWidth(int sqSize) {
    return sqSize * 8;
}

protected int getHeight(int sqSize) {
    return sqSize * 8;
}

private int getSquareSizeWidth(final int width) {
    return (width)/ 8;
}

private int getSquareSizeHeight(final int height) {
    return (height)/8;
}

private int getXCoord(final int x) {
    return x0 + squareSize * (flipped ? 7 - x : x);
}

private int getYCoord(final int y) {
    return y0 + squareSize * (flipped ? y : 7 - y);
}

private void computeOrigins(final int width, final int height) {
   this.x0 = (width  - squareSize *8)/2 ;
    this.y0 = (height - squareSize *8)/2;
}
protected int getMaxHeightPercentage() {
    return 75;
}

}

请注意，上面的 onDraw 方法是在 Chess Board 类中实现的。

我确信这个问题的解决方案在于onMeasure方法，我在想如果我增加每个方 block 的高度那么棋盘会水平拉伸(stretch)并覆盖整个屏幕？谁能告诉我我做错了什么？

Answer 1

好吧，不太确定您想要通过非方形棋盘实现什么目的，这并不是它通常的表示方式。无论如何，仅查看您的代码，下面几行看起来有点可疑:

squareSize=Math.min(getSquareSizeWidth(width),getSquareSizeHeight(height));

和

rect.right= rect.left+squareSize;  // right
rect.bottom=rect.top + squareSize;

因此，您的平铺矩形似乎总是设置为相同的宽度和高度，这是这些行的宽度和高度的最小值。