remove method
Remove items at column colIndex and row rowIndex
Returns the removed item if found or null otherwise
Implementation
T? remove({required int colIndex, required int rowIndex}) {
final rowMap = _rows[rowIndex];
if (rowMap == null) {
return null;
}
final removed = rowMap.remove(colIndex);
if (rowMap.isEmpty) {
_rows.remove(rowIndex);
}
return removed;
}