沿着路径绘制文字

circle = new Path();
circle.addCircle(150, 150, 100, Direction.CW);

private static final String QUOTE = "Now is the time for all " +
"good men to come to the aid of their country." ;
canvas.drawPath(circle, cPaint);
canvas.drawTextOnPath(QUOTE, circle, 0, 20, tPaint);