（4.2.21）刮刮卡特效GuaGuaKa

GuaGuaKA类文件

class GuaGuaKa extends View {
        private Canvas mCanvas = null;
        private Path mPath = null;
        private Paint mPaint = null;
        private Bitmap bitmap_temp = null;
        private Bitmap bitmap = null;
        private Boolean mCompleted = false;
        int x = 0;
        int y = 0;
        private OnCaCompleteListener mOnCompleteListener;

        public GuaGuaKa(Context context,
                OnCaCompleteListener mOnCompleteListener) {
            super(context);
            init(context);
            this.mOnCompleteListener = mOnCompleteListener;
        }

        private void init(Context context) {
            mPath = new Path();
            mPaint = new Paint();
            mPaint.setAlpha(0);
            mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN)); // 设置画笔的痕迹是透明的，从而可以看到背景图片
            mPaint.setAntiAlias(true);
            mPaint.setDither(true);
            mPaint.setStyle(Paint.Style.STROKE);
            mPaint.setStrokeJoin(Paint.Join.ROUND);
            mPaint.setStrokeCap(Paint.Cap.ROUND);
            mPaint.setStrokeWidth(120);

            bitmap = Bitmap.createScaledBitmap(BitmapFactory.decodeResource(
                    getResources(), R.drawable.bg_jiyudianjin_2), screenWidth,
                    screenHeight, true);
            bitmap_temp = Bitmap.createBitmap(screenWidth, screenHeight,
                    Bitmap.Config.ARGB_8888); // 创建临时图片
            mCanvas = new Canvas();
            mCanvas.setBitmap(bitmap_temp);
            mCanvas.drawBitmap(bitmap, 0, 0, null);
        }

        @Override
        protected void onDraw(Canvas canvas) {
            super.onDraw(canvas);
            canvas.drawBitmap(bitmap_temp, 0, 0, null);
            mCanvas.drawPath(mPath, mPaint);
            if (mCompleted) {
                mOnCompleteListener.OnCompleted();
            }
        }

        @Override
        public boolean onTouchEvent(MotionEvent event) {
            int action = event.getAction();
            int currX = (int) event.getX();
            int currY = (int) event.getY();
            switch (action) {
            case MotionEvent.ACTION_DOWN: {
                mPath.reset();
                x = currX;
                y = currY;
                mPath.moveTo(x, y);
            }
                break;
            case MotionEvent.ACTION_MOVE: {
                mPath.quadTo(x, y, currX, currY);
                x = currX;
                y = currY;
                postInvalidate();
            }
                break;
            case MotionEvent.ACTION_UP:
            case MotionEvent.ACTION_CANCEL: {
                mPath.reset();
                new Thread(mRunnable).start();
            }
                break;
            }
            return true;
        }

        /** * 起一个线程来计算已经扫的面积及占总区域的比例 根据区域来判断是否完成 */
        private Runnable mRunnable = new Runnable() {
            @Override
            public void run() {
                int w = getWidth();
                int h = getHeight();
                float wipeArea = 0;
                float totalArea = w * h;
                Bitmap mbitmap = bitmap_temp;
                int[] mPixels = new int[w * h];
                mbitmap.getPixels(mPixels, 0, w, 0, 0, w, h);
                for (int i = 0; i < w; i++)
                    for (int j = 0; j < h; j++) {
                        int index = i + j * w;
                        if (mPixels[index] == 0) {
                            wipeArea++;
                        }
                    }
                if (wipeArea > 0 && totalArea > 0) {
                    int percent = (int) (wipeArea * 100 / totalArea);
                    if (percent > 10) {
                        mCompleted = true;
                        postInvalidate();
                    }
                }
            };
        };

    }

    public interface OnCaCompleteListener {
        public void OnCompleted();
    }

布局文件

    <RelativeLayout  android:id="@+id/layout_anim" android:layout_width="match_parent" android:layout_height="match_parent" android:background="@color/gray_m" android:orientation="vertical" android:visibility="gone" >
    </RelativeLayout>

使用

mAnimLayout.removeAllViews();

        //创建一个
        final TextView txt = new TextView(UtilJiYuActivity.this);
        txt.setText(resultTitle);
        txt.setTextSize(30);
        txt.setTextColor(getResources().getColor(
                R.color.color_util_jydj_txt_color));
        txt.setGravity(Gravity.CENTER);
        LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
                LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
        lp.setMargins(0, 25, 0, 25);
        txt.setLayoutParams(lp);

        mAnimLayout.addView(txt);


        mAnimLayout.addView(new GuaGuaKa(UtilJiYuActivity.this,
                new OnCaCompleteListener() {

                    @Override
                    public void OnCompleted() {

                        mAnimLayout.setVisibility(View.GONE);
                        mResultLayout.setVisibility(View.VISIBLE);
                    }
                }));