TLegend not SetFillColorAlpha by default

[cxwx]

---

_ROOT Version:6.14

---

hi all:
if I have a TLegend;

gStyle-> SetFillColorAlpha(1,0); // not OK

TLegend * l1 …
l1-> SetFillColorAlpha(1,0); //OK

how can I Set Legend FillColorAlpha by default?

[couet]

   TColor *col3 = gROOT->GetColor(3);
   col3->SetAlpha(0.3);
   gStyle->SetLegendFillColor(3);

[cxwx]

that is a way, but this would edit the default color 3 at the same time. that’s not a good way.
could I add a new color?

[couet]

   ci = TColor::GetFreeColorIndex();
   TColor *col = gROOT->GetColor(ci);
   col->SetAlpha(0.3);
   gStyle->SetLegendFillColor(ci);