Question

I have empty TableModel. When I set this model to JTable it hasn’t rows. I want to create one empty row, where user can select value in combo box editor. If user selects not-null value, then second row added and I have one object in model. How can I add empty row, when there is not object for this row in model?

Answer 1

The TableModel is your friend: implement it’s setValueAt method to add a row after setting the value. Here’s an example for doing so by subclassing DefaultTableModel:

    DefaultTableModel model = new DefaultTableModel(1, 3) {

        /** 
         * @inherited <p>
         */
        @Override
        public void setValueAt(Object aValue, int row, int column) {
            super.setValueAt(aValue, row, column);
            if (shouldAddRow(row, column)) {
                addRow(new Object[] {});
            }
        }

        private boolean shouldAddRow(int lastEditedRow, int lastEditedColumn) {
            // implement your logic here
            return lastEditedRow == getRowCount() -1;
        }


    };