通过单击位置从JList获取组件

Question

How can I fetch a component from a JList , with the click location?

I have my own list cell renderer where I insert some panels and labels. Now i want to get eg the label where the user clicked at.

I tried the method list.getComponentAt(evt.getPoint()); but it returns only the entire JList .

Answer 1

I've not tested this, but the basics would be...

1. Use JList#locationToIndex(Point) to get the index of the element at the given point.
2. Get the "element" at the specified index (using JList#getModel#getElementAt(int) ).
3. Get the ListCellRenderer using JList#getCellRenderer .
4. Render the element and get it's Component representation
5. Set the renderer's bounds to the required cell bounds
6. Convert the original Point to the Component s context
7. Use getComponentAt on the renderer...

Possibly, something like...

int index = list.locationToIndex(p);
Object value = list.getModel().getElementAt(int);
Component comp = listCellRenderer.getListCellRendererComponent(list, value, index, true, true);
comp.setBounds(list.getCellBounds(index, index));
Point contextPoint = SwingUtilities.convertPoint(list, p, comp);
Component child = comp.getComponentAt(contextPoint);

Answer 2

MadProgrammer's works fine as long as the user doesn't click outside a cell. If he does that, the index returned by locationToIndex() will be the last index's cell, so the converted point will be "under" the rendered component

To check if the user really clicked a cell you have to do:

int index = list.locationToIndex(p);
if (index > -1 && list.getCellBounds(index, index).contains(p)){
    // rest of MadProgrammer solution
    ...
}