Sets or retrieves the display position of the grid row.
The display position of the grid row is not necessarily the same as the row index in the datasource. It is possible to show only some of the datasource rows (filter) and show them in the different order (sort). The array of the row indices defines which datasource rows correspond to each visible row of the grid and the row position property returns zero-based display position (given the row datasource index).
var value = obj.getRowPosition();
obj.setRowPosition(value);
obj.onRowPositionChanging = function(value){...};
obj.onRowPositionChanged = function(value){...};
obj.onRowPositionError = function(value){...};
obj.setSelectorText(function(r){return this.getRowPosition(r)});