private void drawThreshold(Canvas canvas,float left,float top,float right,float bottom){
  if (left == right || top == bottom)   canvas.drawLine(left,top,right,bottom,style.thresholdPaint);
 else   canvas.drawRect(left,top,right,bottom,style.thresholdPaint);
}

private void drawThreshold ( Canvas canvas , float left , float top , float right , float bottom ) { if ( left == right || top == bottom ) canvas . drawLine ( left , top , right , bottom , style . thresholdPaint ) ; else canvas . drawRect ( left , top , right , bottom , style . thresholdPaint ) ; }
draw a threshold line or band on the labels or values axis . if same values or same label index have been given then a line will be drawn rather than a band .
