tornadofx-guide

Advanced Data Controls
Figure 5.2 - A custom cell rendering for ListView
The cellFormat function lets you configure the text and/or graphic property of the cell
whenever it comes into view on the screen. The cells themselves are reused, but whenever
the ListView asks the cell to update its content, the cellFormat function is called. In our
example we only assign to graphic , but if you just want to change the string representation
you should assign it to text . It is completely legitimate to assign it to both text and
graphic . The values will automatically be cleared by the cellFormat function when a
certain list cell is not showing an active item.
Note that assigning new nodes to the graphic property every time the list cell is asked to
update can be expensive. It might be fine for many use cases, but for heavy node graphs, or
node graphs where you utilize binding towards the UI components inside the cell, you should
cache the resulting node so the Node graph will only be created once per node. This is done
using the cache wrapper in the above example.
202