In many situations, you may want columns to map values so cells display a value that is different from what is actually stored in the grid.
For example, you may have a 'rating' column with values ranging from zero to three, and you would like to display the strings 'Low', 'Medium', or 'High' instead.
Or maybe you have a 'customer' column that contains the customer ID, and you would like to display the customer name instead.
You could accomplish both tasks using the formatItem event, but the FlexGrid provides a better alternative: DataMaps. If you set a column's dataMap property to an instance of a DataMap, the grid will use it to:
For example, the grid below has a 'Customer' column with a DataMap that associates customer names and IDs. The data source contains customer IDs, but the grid shows their names instead, and provides a drop-down list for selecting the customer for each item.
The grid also assigns a dataMap to the 'Country' column. In this case, the map is just a string array with the country names. There is no real mapping, but you still get the drop-down list to pick from. Users will not be able to enter any countries that are not on the list.