Having an action column is a convenient way to work with a particular row in a treepanel. However, I find that it's excessive to have the same icon always displayed for every single row in the treepanel. It'd be much more elegant to display the action icon for the given row only when mousing over that row.

I have tried a few things but haven't been able to piece everything together...

Here is how I am listening for mouse over events:

xtype: 'treepanel',
        items: [{
            icon: 'myicon.png',              
            handler: function(grid, rowIndex, colIndex) {
                // do something when icon is clicked

listeners: {
    itemmouseenter: function( view, record, item, rowIndex, e, eOpts ) {
        // show the icon - is this possible?
    itemmouseleave: function( view, record, item, rowIndex, e, eOpts ) {
        // hide the icon

Any suggestions as to how to show/hide the icon from within the itemmouseenter/itemmouseleave function? Any ideas are much appreciated.
Thank you.