The position of the first returned row, null if this data is not for a viewport.
A lazily computed array of all rows available on the client.
Reads a row object from the viewport, based on its position in the table.
Reads a specific cell from the table, by row key and column.
the row in the table to get data from
the column to read
the value in the table
The server-specified Format to use for the cell at the given position.
the row to read
the column to read
a Format instance with any server-specified details
Extends TableData, but only contains data in the current viewport. The only API change from TableData is that ViewportData also contains the offset to this data, so that the actual row number may be determined.
For viewport subscriptions, it is not necessary to read with the key, only with the position.
Do not assume that the first row in `rows` is the first visible row, because extra rows may be provided for easier scrolling without going to the server.