public class MainActivity extends AppCompatActivity {  @Override  protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);  }}

public class GuaTwo extends View {  /*第一種方法*/  private Path mPath;//手刮動的path，過程  private Paint mOutterPaint;//繪制mPath的畫筆  private Canvas mCanvas;//臨時畫布  private Bitmap mBitmap;//臨時圖片  //記錄用戶path每次的開始坐標值  private int mLastX;  private int mLastY;  private Bitmap mOutterBitmap;//圖片遮罩，就是手刮動，要擦掉的那張圖  public GuaTwo(Context context) {    this(context, null);  }  public GuaTwo(Context context, AttributeSet attrs) {    this(context, attrs, 0);  }  public GuaTwo(Context context, AttributeSet attrs, int defStyle) {    super(context, attrs, defStyle);    init();  }  @Override  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {    super.onMeasure(widthMeasureSpec, heightMeasureSpec);    //獲得控件的寬高    int width = getMeasuredWidth();    int height = getMeasuredHeight();    //初始化bitmap    mBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);    mCanvas = new Canvas(mBitmap);    //設置畫筆屬性    setupOutPaint();    mCanvas.drawColor(Color.parseColor("#c0c0c0"));  }  @Override  protected void onDraw(Canvas canvas) {    mOutterPaint.setStyle(Paint.Style.STROKE);    mOutterPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_OUT));//Mode.DST_OUT改模式就類似橡皮檫，這個屬性設置是關鍵    canvas.drawBitmap(mOutterBitmap, 0, 0, null);    canvas.drawBitmap(mBitmap, 0, 0, null);    mCanvas.drawPath(mPath, mOutterPaint);  }  @Override  public boolean onTouchEvent(MotionEvent event) {    int action = event.getAction();    int x = (int) event.getX();    int y = (int) event.getY();    switch (action) {      case MotionEvent.ACTION_DOWN://按下        //記錄按下的時候的X和Y值，以便于之后移動的時候繪制        mLastX = x;        mLastY = y;        mPath.moveTo(mLastX, mLastY);        break;      case MotionEvent.ACTION_MOVE://移動        //拿到用戶移動的X絕對值，Y軸絕對值        int dx = Math.abs(x - mLastX);        int dy = Math.abs(y - mLastY);        //用戶滑動超過3像素才會改變，這個可以不做，做只是為了避免很頻繁的響應而已。        if (dx > 3 || dy > 3) {          mPath.lineTo(x, y);        }        mLastX = x;        mLastY = y;        break;    }    invalidate();//刷新UI    return true;  }  /**   * 繪制path（也就是手刮動的path來繪制） 的畫筆屬性   * 類似橡皮擦   */  private void setupOutPaint() {    mOutterPaint.setColor(Color.RED);    mOutterPaint.setAntiAlias(true);    mOutterPaint.setDither(true);    mOutterPaint.setStrokeJoin(Paint.Join.ROUND);//設置圓角    mOutterPaint.setStrokeCap(Paint.Cap.ROUND);    mOutterPaint.setStyle(Paint.Style.FILL);    mOutterPaint.setStrokeWidth(60);//設置畫筆寬度  }  /**   * 初始化信息   */  private void init() {    mOutterPaint = new Paint();    mPath = new Path();    mOutterBitmap = BitmapFactory.decodeResource(getResources(),        R.drawable.mein);  }

private Path mPath;//手刮動的path，過程  private Paint mOutterPaint;//繪制mPath的畫筆  private Canvas mCanvas;  private Bitmap mBitmap;  //記錄用戶path每次的開始坐標值  private int mLastX;  private int mLastY;  private Bitmap mOutterBitmap;//圖片遮罩，就是手刮動，要擦掉的那張圖  private String mText;//刮獎文本信息  private Rect mTextBound;  private Paint mBackPaint;//刮獎信息的畫筆  public GuaTwo(Context context) {    this(context, null);  }  public GuaTwo(Context context, AttributeSet attrs) {    this(context, attrs, 0);  }  public GuaTwo(Context context, AttributeSet attrs, int defStyle) {    super(context, attrs, defStyle);    init();  }  @Override  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {    super.onMeasure(widthMeasureSpec, heightMeasureSpec);    //獲得控件的寬高    int width = getMeasuredWidth();    int height = getMeasuredHeight();    //初始化bitmap    mBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);    mCanvas = new Canvas(mBitmap);//用指定的位圖構造一個畫布來繪制。    //設置畫筆屬性    setupOutPaint();    setUpBackPaint();//    mCanvas.drawColor(Color.parseColor("#c0c0c0"));    mCanvas.drawRoundRect(new RectF(0, 0, width, height), 30, 30,        mOutterPaint);//用mOutterPaint畫圓角矩形    mCanvas.drawBitmap(mOutterBitmap, null, new Rect(0, 0, width, height),        null);//在剛剛畫的圓角矩形上面再畫一個bitmap圖片，讓圖片大小和圓角矩形大小相關聯  }  @Override  protected void onDraw(Canvas canvas) {    mOutterPaint.setStyle(Paint.Style.STROKE);    mOutterPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_OUT));//Mode.DST_OUT改模式就類似橡皮檫，這個屬性設置是關鍵    canvas.drawText(mText, (getWidth() - mTextBound.width()) / 2, getHeight() / 2 - mTextBound.height() / 2, mBackPaint);//把獲獎信息放在正中間    mCanvas.drawPath(mPath, mOutterPaint);    canvas.drawBitmap(mBitmap, 0, 0, null);  }  @Override  public boolean onTouchEvent(MotionEvent event) {    int action = event.getAction();    int x = (int) event.getX();    int y = (int) event.getY();    switch (action) {      case MotionEvent.ACTION_DOWN://按下        //記錄按下的時候的X和Y值，以便于之后移動的時候繪制        mLastX = x;        mLastY = y;        mPath.moveTo(mLastX, mLastY);        break;      case MotionEvent.ACTION_MOVE://移動        //拿到用戶移動的X絕對值，Y軸絕對值        int dx = Math.abs(x - mLastX);        int dy = Math.abs(y - mLastY);        //用戶滑動超過3像素才會改變，這個可以不做，做只是為了避免很頻繁的相應而已。        if (dx > 3 || dy > 3) {          mPath.lineTo(x, y);        }        mLastX = x;        mLastY = y;        break;    }    invalidate();//刷新UI    return true;  }  private void setUpBackPaint() {    mBackPaint.setColor(Color.RED);    mBackPaint.setStyle(Paint.Style.FILL);    mBackPaint.setTextSize(60);    //獲得當前畫筆繪制文本的寬和高    mBackPaint.getTextBounds(mText, 0, mText.length(), mTextBound);  }  *//**   * 繪制path（也就是手刮動的path來繪制） 的畫筆屬性   * 類似橡皮擦   *//*  private void setupOutPaint() {    mOutterPaint.setColor(Color.RED);    mOutterPaint.setAntiAlias(true);    mOutterPaint.setDither(true);    mOutterPaint.setStrokeJoin(Paint.Join.ROUND);//設置圓角    mOutterPaint.setStrokeCap(Paint.Cap.ROUND);    mOutterPaint.setStyle(Paint.Style.FILL);    mOutterPaint.setStrokeWidth(60);//設置畫筆寬度  }  *//**   * 初始化信息   *//*  private void init() {    mOutterPaint = new Paint();    mPath = new Path();    mOutterBitmap = BitmapFactory.decodeResource(getResources(),        R.drawable.huahua);    mText = "您中獎了！";    mTextBound = new Rect();    mBackPaint = new Paint();  }

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  xmlns:tools="http://schemas.android.com/tools"  android:id="@+id/activity_main"  android:layout_width="match_parent"  android:layout_height="match_parent"  android:paddingBottom="@dimen/activity_vertical_margin"  android:paddingLeft="@dimen/activity_horizontal_margin"  android:paddingRight="@dimen/activity_horizontal_margin"  android:paddingTop="@dimen/activity_vertical_margin"  tools:context="com.bwie.test.guaguale.MainActivity">  <com.bwie.test.guaguale.GuaTwo    android:layout_width="wrap_content"    android:layout_height="wrap_content" /></RelativeLayout>