qt - Finding out how many items fit in the QTreeView (number of rows visible on the screen) -

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i'm sure there's easy way number, can't find any.

it can't determined empty view because can vary depending on items' content. if there items in view, can calculate qabstractitemview::visualrect , intersect viewport()'s rect() see if particular item visible. can iterate on rows , check if item visible. example:

for(int row = 0; row < view.model()->rowcount(); row++) {   if (!view.visualrect(view.model()->index(row, 0)).intersects(view.viewport()->rect())) {     return row;   } }

however works if have top level items , have enough items fill viewport.

alternatively, can call view.indexat(qpoint(0, 0)) , view.indexat(qpoint(0, view.viewport()->height())) , compare indexes. if these indexes don't share same parent, counting rows become troublesome.


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