Notification when a checkbox in a JTable is checked

Question

I've searched for this for quite a while and haven't found a clear example anywhere. I'm a Java newbee using NetBeans. I have a boolean value in the first column of a JTable (called "Enabled") and I have some plugin code that I need to call to see if it has the settings it needs in order to be enabled, and if not, display a message box and prevent Enabled from being checked.

All I really need is for a function to be called when the checkbox is checked and I can take it from there. Does anyone have an example of how to do this?

Thanks for your help!

Harry

Answer 1

You probably want a TableModelListener, as discussed in Listening for Data Changes. Alternatively, you can use a custom editor, as discussed in Concepts: Editors and Renderers and the following section.

Answer 2

All I really need is for a function to be called when the checkbox is checked

When the checkbox is checked then the value will be changed in the model, which is probably not what your want. I would think you want to prevent the checking of the checkbox in the first place.

The way to prevent a cell from being editable is to override the isCellEditable(...) method of JTable. By overriding this method you can dynamically determine if the cell should be editable or not.

JTable table = new JTable( ... )
{
    public boolean isCellEditable(int row, int column)
    {
        int modelColumn = convertColumnIndexToModel( column );

        if (modelColumn == yourBooleanColumn)
            return isTheBooleanForThisRowEditable(row);
        else
            return super.isCellEditable(row, column);
    }
};

And a fancier approach would be to create a custom renderer so that the check box looks "disabled" even before the user attempts to click on the cell. See the link provided by trashgod on renderers.