Thank you!
I think I should make changes in showtabheaders, like
act.AddView(B, (width*i + mLeft)*1dip, (mTop+mHeight-mTabHeaderHeight*1dip), width*1dip, mTabHeaderHeight*1dip)
and in AddTab
mAct.AddView(pnl, mLeft*1dip, 1dip, mWidth*1dip, mHeight*1dip)
Am I right? Then I will continue to experiment
Thank you
Peter