Android 自定义View 刮刮乐—呱奖

package com.example.guagua;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.Bitmap.Config;
import android.graphics.PorterDuff.Mode;
import android.graphics.PorterDuffXfermode;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;

public class GuaguaKaView extends View {
	private Paint mPaint, mTPaint;
	private Rect mbound = new Rect();
	private Bitmap mBitmap;
	private Path mPath;
	private Bitmap mHongbao;
	private Canvas mCanvas;

	public GuaguaKaView(Context context, AttributeSet attrs) {
		this(context, attrs, 0);
		// TODO Auto-generated constructor stub
	}

	public GuaguaKaView(Context context) {
		super(context, null);
		// TODO Auto-generated constructor stub
	}

	private Context mContext;

	public GuaguaKaView(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);

		mContext = context;
		//初始化画笔
		initPaint();
		//初始化path
		initPath();
		//初始化图片资源
		setUpBitmap();

	}

	private void initPaint() {
		mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
		mPaint.setStyle(Paint.Style.STROKE);
		mPaint.setStrokeCap(Paint.Cap.ROUND);
		mPaint.setDither(true);
		mPaint.setStrokeWidth(15);
		mPaint.setStrokeJoin(Paint.Join.ROUND);
		// mPaint.setColor(0xaa0000ff);

		mTPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
		mTPaint.setStyle(Paint.Style.FILL);
		mTPaint.setStrokeCap(Paint.Cap.ROUND);
		mTPaint.setDither(true);
		mTPaint.setColor(0xaaff0000);
		mTPaint.setTextSize(30);
		measureText();

	}

	private void setUpBitmap() {
		//先绘制dst  再设置xfermode  最后绘制src
		mBitmap = BitmapFactory.decodeResource(mContext.getResources(),
				R.drawable.hongbao);
		mHongbao = Bitmap.createBitmap(mBitmap.getWidth(), mBitmap.getHeight(),
				Config.ARGB_8888);
		mCanvas = new Canvas(mHongbao);
		mCanvas.drawColor(Color.parseColor("#c0c0c0"));
		mCanvas.drawBitmap(mBitmap, 0, 0, null);
	}

	@Override
	protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
		if (MeasureSpec.getMode(widthMeasureSpec) == MeasureSpec.AT_MOST) {
			widthMeasureSpec = MeasureSpec.makeMeasureSpec(mHongbao.getWidth(),
					MeasureSpec.AT_MOST);
		}
		if (MeasureSpec.getMode(heightMeasureSpec) == MeasureSpec.AT_MOST) {
			heightMeasureSpec = MeasureSpec.makeMeasureSpec(
					mHongbao.getHeight(), MeasureSpec.AT_MOST);
		}

		super.onMeasure(widthMeasureSpec, heightMeasureSpec);
	}

	private void initPath() {
		mPath = new Path();

	}

	private String text = "1000.000万元";

	void measureText() {
		mTPaint.getTextBounds(text, 0, text.length(), mbound);

	}

	@Override
	protected void onDraw(Canvas canvas) {
		canvas.drawText(text, getWidth() / 2 - mbound.width() / 2, getHeight()
				/ 2 + mbound.height() / 2, mTPaint);
		if (mComplete)
			return;
		drawPath();

		canvas.drawBitmap(mHongbao, 0, 0, null);

	}

	/**
	 * 设置Xfermode 模式  PorterDuff.Mode.DST_OUT 取下层绘制非交集部分
	 */
	private void drawPath() {
	
		mPaint.setXfermode(new PorterDuffXfermode(Mode.DST_OUT));
		mCanvas.drawPath(mPath, mPaint);
	}

	@Override
	public boolean onTouchEvent(MotionEvent event) {
		int action = event.getAction();
		int x = (int) event.getX();
		int y = (int) event.getY();
		int downx = 0;
		int downy = 0;
		switch (action) {
		case MotionEvent.ACTION_DOWN:
			downx = x;
			downy = y;

			mPath.moveTo(downx, downy);
			break;

		case MotionEvent.ACTION_MOVE:
			int distanceX = x - downx;
			int distanceY = x - downy;
			//当触摸超过距离5的时候才刮
			if (Math.abs(distanceX) > 5 || Math.abs(distanceY) > 5) {

				mPath.lineTo(x, y);
				invalidate();
			}
			downx = x;
			downy = y;
			break;
		case MotionEvent.ACTION_UP:
			cheakArea();
			break;
		}

		return true;
	}

	private boolean mComplete = false;

	private void cheakArea() {
		new Thread(new Runnable() {
			int w = mHongbao.getWidth();
			int h = mHongbao.getHeight();
			//红包的像素总合
			int HBATotolrea = w * h;
			//存储图片像素点的值
			int[] mHongbaoArea = new int[HBATotolrea];
			//当前面积
			int mCurArea;
			private String TAG;

			@Override
			public void run() {
				//得到每个像素的值
				mHongbao.getPixels(mHongbaoArea, 0, w, 0, 0, w, h);
				for (int i = 0; i < w; i++) {
					for (int j = 0; j < h; j++) {
						int index = w * i + j;
						if (mHongbaoArea[index] == 0) {
							mCurArea += 1;

						}

					}

					int a = mCurArea * 100 / HBATotolrea;
					
					//当刮到大于60%的时候 就显示结果
					if (a > 60) {
						mComplete = true;
					}

				}

			}

		}).start();

	}