IW 15.1.20 TIWRegions

[Richard]

Maybe something like (in C++):
leftRegion->Visible = false ;
rightRegion->Invalidate() ;

Thank you Stephan for your answer. Unfortunately this doesn't work; the only way I have found so far is to set the leftregion.width to 0.

---

Set StyleRenderOptions.UseDisplay to TRUE.

This will make IW use the Display attribute to hide it, instead of visibility attribute. This should do it.

Thank you Alexandre.
Do you mean that using UseDisplay to TRUE or False will Show / Hide the leftRegion , and if Hided , the right region will fill the available space? I tried that , but the behavior is the same: rightRegion doesn't fill the available space contrarily to what happened with IW14