BMFText constructor
- {@required String text,
 - @required BMFCoordinate position,
 - Color bgColor,
 - Color fontColor: Colors.blue,
 - int fontSize: 12,
 - BMFTypeFace typeFace,
 - int alignY: BMFHorizontalAlign.ALIGN_CENTER_HORIZONTAL,
 - int alignX: BMFVerticalAlign.ALIGN_CENTER_VERTICAL,
 - double rotate: 0,
 - int zIndex: 0,
 - bool visible: true}
 
BMFText构造方法
Implementation
BMFText(
    {@required this.text,
    @required this.position,
    this.bgColor,
    this.fontColor: Colors.blue,
    this.fontSize: 12,
    this.typeFace,
    this.alignY: BMFHorizontalAlign.ALIGN_CENTER_HORIZONTAL,
    this.alignX: BMFVerticalAlign.ALIGN_CENTER_VERTICAL,
    this.rotate: 0,
    int zIndex: 0,
    bool visible: true})
    : super(zIndex: zIndex, visible: visible);