setShapeGradientStartColor,setShapeGradientEndColor android7.x系列闪退

setShapeGradientEndColor,setShapeGradientEndColor在android7.x系统会闪退
java.lang.NullPointerException: Attempt to invoke virtual method 'int android.graphics.drawable.GradientDrawable$Orientation.ordinal()' on a null object reference