1 protected void onDraw(Canvas canvas) {
 2         int count = getLineCount(); // method entends from TextView.
 3         Rect r = mRect;
 4         Paint paint = mPaint;
 5         
 6         //第一次画第一条线。以后每次输入，换行时仍然检测，继续画线
 7         for (int i = 0; i < count; i++) {
 8             int baseline = getLineBounds(i, r);
 9             baseline += outY;
10             //添加一个固定值outY，使画线向下平移一定高度，这样光标就不会压线了
11             canvas.drawLine(0, baseline + 1, r.right, baseline + 1, paint);
12         }
13         
14       //根据判定条件，画出固定条数的线
15         if(count < linecount){
16             for (int j = count; j < linecount; j++) {
17                 float baseline = basicline + outY + j*linedistance;
18                 canvas.drawLine(0, baseline + 1, r.right, baseline + 1, paint);
19                 //get lineHeight 可以使用getLineHeight();
20             }
21         }
22         super.onDraw(canvas);
23     }