Android中的像素绘图

Question

我正在尝试制作一个基本的像素绘图应用程序，该应用程序将绘图组件拆分为10x10的网格，并使用路径填充了拖动的路径通过时填充的网格元素。我是应用程序设计的新手，目前正在尝试通过在每次调用TouchEvent时更新位图并填充触摸位置周围的10％x和10％y区域来实现此目的，但这似乎不起作用。如果不使用drawPath，就无法使用路径作为此类程序的输入来找到任何东西，这不是我想要的！任何帮助将不胜感激。我已经为我的paintView文件添加了代码。

谢谢！

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BlurMaskFilter;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.EmbossMaskFilter;
import android.graphics.MaskFilter;
import android.graphics.Paint;
import android.graphics.Path;
import android.util.AttributeSet;
import android.util.DisplayMetrics;
import android.view.MotionEvent;
import android.view.View;



import java.util.ArrayList;

public class PaintView extends View {

    public static int BRUSH_SIZE = 20;
    public static final int DEFAULT_COLOR = Color.RED;
    public static final int DEFAULT_BG_COLOR = Color.WHITE;
    private static final float TOUCH_TOLERANCE = 4;
    private float mX, mY;
    private Path mPath;
    private Paint mPaint;
    private ArrayList<FingerPath> paths = new ArrayList<>();
    private int currentColor;
    private int backgroundColor = DEFAULT_BG_COLOR;
    private int strokeWidth;
    public Bitmap mBitmap;
    private Canvas mCanvas;
    private Paint mBitmapPaint = new Paint(Paint.DITHER_FLAG);


    public PaintView(Context context) {
        this(context, null);
    }

    public PaintView(Context context, AttributeSet attrs) {
        super(context, attrs);
        mPaint = new Paint();
        mPaint.setAntiAlias(true);
        mPaint.setDither(true);
        mPaint.setColor(DEFAULT_COLOR);
        mPaint.setStyle(Paint.Style.STROKE);
        mPaint.setStrokeJoin(Paint.Join.ROUND);
        mPaint.setStrokeCap(Paint.Cap.ROUND);
        mPaint.setXfermode(null);
        mPaint.setAlpha(0xff);

    }

    public void init(DisplayMetrics metrics) {
        int height = metrics.heightPixels;
        int width = metrics.widthPixels;

        mBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
        mCanvas = new Canvas(mBitmap);

        currentColor = DEFAULT_COLOR;
        strokeWidth = BRUSH_SIZE;
    }

    public void clear() {
        backgroundColor = DEFAULT_BG_COLOR;
        paths.clear();
        invalidate();
    }

    private Bitmap pixelate(float xc, float yc, Bitmap bitmap){
        int height = bitmap.getHeight();
        int width = bitmap.getWidth();
        float decx = xc/(width/10);
        int xs = (int)(0.1*decx)*width;
        float decy = yc/(height/10);
        int ys = (int)(0.1*decy)*height;

        Bitmap bmOut = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);




                for(int x = xs; x < xs + 0.1*width;x++){
                    if (x < width) {
                        for (int y = ys; y < ys + 0.1*width; y++) {
                            if (y < height) {
                                bmOut.setPixel(x, y, Color.argb(255, 255, 0, 0));
                            }
                        }
                    }
                }


        return bmOut;
    }




    @Override
    protected void onDraw(Canvas canvas) {
        canvas.save();
        mCanvas.drawColor(backgroundColor);

        for (FingerPath fp : paths) {
            mPaint.setColor(fp.color);
            mPaint.setStrokeWidth(fp.strokeWidth);
            mPaint.setMaskFilter(null);

            mCanvas.drawPath(fp.path, mPaint);

        }
        canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);
        canvas.restore();
    }

    private void touchStart(float x, float y) {
        mPath = new Path();
        FingerPath fp = new FingerPath(currentColor, strokeWidth, mPath);
        paths.add(fp);

        mPath.reset();
        mPath.moveTo(x, y);
        mX = x;
        mY = y;
    }

    private void touchMove(float x, float y) {
        float dx = Math.abs(x - mX);
        float dy = Math.abs(y - mY);

        if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) {
            mPath.quadTo(mX, mY, (x + mX) / 2, (y + mY) / 2);
            mX = x;
            mY = y;
        }
    }

    private void touchUp() {
        mPath.lineTo(mX, mY);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        float x = event.getX();
        float y = event.getY();

        switch(event.getAction()) {
            case MotionEvent.ACTION_DOWN :
                touchStart(x, y);
                mBitmap = pixelate(x, y, mBitmap);
                invalidate();
                break;
            case MotionEvent.ACTION_MOVE :
                touchMove(x, y);
                mBitmap = pixelate(x,y,mBitmap);
                invalidate();
                break;
            case MotionEvent.ACTION_UP :
                touchUp();
                mBitmap = pixelate(x,y,mBitmap);
                invalidate();
                break;
        }

        return true;
    }

}