QTableView not working as expected.

[ChrisW67]

You don't need line 23 in your original post.

Maybe:

table->horizontalHeader()->setStretchLastSection(true);
OR
table->horizontalHeader()->setResizeMode(0, QHeaderView::Stretch);

table->horizontalHeader()->setStretchLastSection(true);
OR
table->horizontalHeader()->setResizeMode(0, QHeaderView::Stretch);

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are more to your liking?