Grid Field with fix number of insert

Dears im using a!gridField and add button to the grid is there a way to make the insert or the add to be fixed number .

ex:

firstColumnContents: {
a!gridField(
label: "",
labelPosition: "ABOVE",
totalCount: 7,
columns: {
.......

i changes the total count to 7 but when i add any new record this message will appear is there a way to validate the or give validation message that you cant add more than 7 records.

Error message :
Could not display interface. Please check definition and inputs.

Interface Definition: Expression evaluation error at function a!gridField [line 135]: A grid component [label=“”] has an invalid value for “totalCount”. “totalCount” must not be null or less than the number of items in any of the “data” arrays, but “totalCount” was 7 and the largest column data array had 8 items.

Thanks

OriginalPostID-245291