I am new to vaadin and i try to create a grid looking like this:
| Header1 | Header 2 | Header 3 | Header 4 |
Col1 | Col2 | Col3 | Col4| Col5| Col6| Col7| Col8| Col9 | Col1 |
i am using
grid.prependHeaderRow().join(col3, col4)
grid.prependHeaderRow().join(col5, col6)
grid.prependHeaderRow().join(col7, col8)
grid.prependHeaderRow().join(col9, col10)
But it end with a grid that looks like this:
| Header 4 |
| Header 3 |
| Header 2 |
| Header1 |
Col1 | Col2 | Col3 | Col4| Col5| Col6| Col7| Col8| Col9 | Col10 |
Not sure what i did wrong since this is how it was described in the tutorial https://vaadin.com/docs/v14/flow/components/tutorial-flow-grid.html#grouping-columns