Java Swing: JList with ListCellRenderer selected item different height

Question

I\'m making a custom ListCellRenderer. I know that you can have different dimensions for each individual cell. But now I want to have a different dimension for the selected

Answer 1

I just implemented this feature. The problem is, that the cell renderer is asked twice for rendering a cell. In the first round all list entries are rendered without selection, then the selected cells are rendered again using selection. So if you provide a preferred size in the first round, it is cached and also used for the second round.

The trick is to ignore the isSelected boolean parameter in the getListCellRendererComponent and to figure out the selection state by checking if list.getSelectedIndices() contains the given index.

But, I still have the problem, that after the list is made visible, the height of the rendered components are sometimes to large/small. After resizing the list by mouse everything is fine again. I played around with validate/revalidate, repaint, reset of cached heights, but nothing worked. Swing is sometimes a bit strange...