获得触摸点的坐标

@Override public boolean onTouchEvent(MotionEvent event) { 
            int action = event.getAction(); 
            mCurDown = action == MotionEvent.ACTION_DOWN 
                    || action == MotionEvent.ACTION_MOVE; 
            int N = event.getHistorySize(); 
            for (int i=0; i<N; i++) { 
                //Log.i("TouchPaint", "Intermediate pointer #" + i); 
                drawPoint(event.getHistoricalX(i), event.getHistoricalY(i), 
                        event.getHistoricalPressure(i), 
                        event.getHistoricalSize(i)); 
            } 
            drawPoint(event.getX(), event.getY(), event.getPressure(), 
                    event.getSize()); 
            return true; 
        } 
 
private void drawPoint(float x, float y, float pressure, float size) { 
            //Log.i("TouchPaint", "Drawing: " + x + "x" + y + " p=" 
            //        + pressure + " s=" + size); 
            mCurX = (int)x; 
            mCurY = (int)y; 
            mCurPressure = pressure; 
            mCurSize = size; 
            mCurWidth = (int)(mCurSize*(getWidth()/3)); 
            if (mCurWidth < 1) mCurWidth = 1; 
            if (mCurDown && mBitmap != null) { 
                int pressureLevel = (int)(mCurPressure*255); 
                mPaint.setARGB(pressureLevel, 255, 255, 255); 
                mCanvas.drawCircle(mCurX, mCurY, mCurWidth, mPaint); 
                mRect.set(mCurX-mCurWidth-2, mCurY-mCurWidth-2, 
                        mCurX+mCurWidth+2, mCurY+mCurWidth+2); 
                invalidate(mRect); 
            } 
            mFadeSteps = 0; 
        }