paintRect method
Implementation
Rect? paintRect(String screenPT){
if(measured){
var data = measuredPT(screenPT);
if(data != null){
return data;
}
/// 如果没有现成的需要计算
var range = cellRange(screenPT);
if(range != null){
final fromStartCell = gKeyMappedValues[range.$1];
final toEndCell = gKeyMappedValues[range.$2];
if(fromStartCell != null && fromStartCell.$2 != null && toEndCell != null && toEndCell.$2 != null){
return fromStartCell.$2!.expandToInclude(toEndCell.$2!);
}
}
}
return null;
}