shouldRepaint method
是否需要重绘
Implementation
@override
bool shouldRepaint(StaggerTextWaterMarkPainter oldPainter) {
return oldPainter.rotate != rotate ||
oldPainter.text != text ||
oldPainter.text2 != text2 ||
oldPainter.staggerAxis != staggerAxis ||
oldPainter.padding1 != padding1 ||
oldPainter.padding2 != padding2 ||
oldPainter.textDirection != textDirection ||
oldPainter.textStyle != textStyle;
}