JavaScript Grid: Row Object (aka Row Node)

A Row Node represents one row of data. The Row Node will contain a reference to the data item your application provided as well as other runtime information about the row. The Row Node contains attributes, methods and emits events. Additional attributes are used if the Row Node is a group.

All Row Node Attributes

`id`	Unique ID for the node. Either provided by the application, or generated by the grid if not.
`data`	The data as provided by the application.
`displayed`	This will be `true` if it has a rowIndex assigned, otherwise `false`.
`parent`	The parent node to this node, or empty if top level.
`level`	How many levels this node is from the top when grouping.
`uiLevel`	How many levels this node is from the top when grouping in the UI (only different to `parent` when `groupRemoveSingleChildren=true`).
`group`	`true` if this node is a group node (i.e. has children).
`rowPinned`	`'top'` or `'bottom'` if pinned row, otherwise `null` or `undefined`.
`childIndex`	Index of this row with respect to its parent when grouping. Changes when data is sorted.
`firstChild`	`true` if this is the first child in this group. Changes when data is sorted.
`lastChild`	`true` if this is the last child in this group. Changes when data is sorted.
`stub`	Used by server-side row model. `true` if this row node is a stub. A stub is a placeholder row with loading icon while waiting from row to be loaded.
`rowHeight`	The row height in pixels.
`rowIndex`	The current row index. If the row is filtered out or in a collapsed group, this value will be `null`.
`rowTop`	The row top position in pixels.
`quickFilterAggregateText`	If using quick filter, stores a string representation of the row for searching against.

Group Node Attributes

`groupData`	If using grid grouping, contains the group values for this group.
`aggData`	If using grid grouping and aggregation, contains the aggregation data.
`key`	The key for the grouping e.g. Ireland, UK, USA.
`field`	The field (string) we are grouping on e.g. `'country'`.
`rowGroupColumn`	The row group column used for this group, e.g. the Country column instance.
`rowGroupIndex`	If doing in-memory (client-side) grouping, this is the index of the group column this cell is for. This will always be the same as the level, unless we are collapsing groups, i.e. `groupRemoveSingleChildren=true`.
`expanded`	`true` if group is expanded, otherwise `false`.
`footer`	`true` if row is a footer. Footers have `group = true` and `footer = true`.
`allLeafChildren`	All lowest level nodes beneath this node, no groups.
`childrenAfterGroup`	Children of this group. If multi levels of grouping, shows only immediate children.
`childrenAfterFilter`	Filtered children of this group.
`childrenAfterSort`	Sorted children of this group.
`allChildrenCount`	Number of children and grandchildren.
`leafGroup`	`true` if this node is a group and the group is the bottom level in the tree.
`sibling`	If using footers, reference to the footer node for this group.

Row Node Methods

`setSelected(newValue: boolean, clearSelection: boolean)`	Select (or deselect) the node. `newValue=true` for selection, `newValue=false` for deselection. If selecting, then passing `true` for `clearSelection` will select the node exclusively (i.e. NOT do multi select). If doing deselection, `clearSelection` has no impact.
`isSelected()`	Returns `true` if node is selected, `false` if the not isn't selected or `undefined` if it's partially selected (group where not all children are selected).
`addEventListener(eventType: string, listener: Function)`	Add an event listener. Currently only `rowSelected` event supported.
`removeEventListener(eventType: string, listener: Function)`	Remove event listener.
`resetQuickFilterAggregateText()`	The first time `quickFilter` runs, the grid creates a one-off string representation of the row. This string is then used for the quick filter instead of hitting each column separately. When you edit, using grid editing, this string gets cleared down. However if you edit without using grid editing, you will need to clear this string down for the row to be updated with the new values. Otherwise new values will not work with the `quickFilter`.
`depthFirstSearch(callback)`	Perform a depth-first search of this node and its children.
`setRowHeight(height)`	Sets the row height. Call if you want to change the height initially assigned to the row. After calling, you must call `api.onRowHeightChanged()` so the grid knows it needs to work out the placement of the rows.
`setData(newData)`	Sets the data for this item. Results in the entire row getting refreshed.

Events on Row Nodes

The following events can be listened to on rowNodes:

`rowSelected`	Row was selected or unselected.
`mouseEnter`	Mouse has entered the row.
`mouseLeave`	Mouse has left the row.
`cellChanged`	One cell value has changed.
`allChildrenCountChanged`	`allChildrenCount` has changed.
`dataChanged`	`rowData` has changed.
`heightChanged`	`rowHeight` has changed.
`topChanged`	`rowTop` has changed.
`firstChildChanged`	`firstChild` has changed.
`lastChildChanged`	`lastChild` has changed.
`childIndexChanged`	`childIndex` has changed.
`rowIndexChanged`	`rowIndex` has changed.
`expandedChanged`	`expanded` has changed.
`uiLevelChanged`	`uiLevel` has changed.

Row Node Events

All events fired by the rowNode are synchronous (events are normally asynchronous). The grid is also listening for these events internally. This means that when you receive an event, the grid may still have some work to do (e.g. if rowTop changed, the grid UI may still have to update to reflect this change). It is also best you do not call any grid API functions while receiving events from the rowNode (as the grid is still processing). Instead, it is best to put your logic into a timeout and call the grid in another VM tick.

When adding event listeners to a row, they will stay with the row until the row is destroyed. This means if the row is taken out of memory (pagination or virtual paging) then the listener will be removed. Likewise, if you set new data into the grid, all listeners on the old data will be removed.

Be careful when adding listeners to rowNodes in cell renderers that you remove the listener when the rendered row is destroyed due to row virtualisation. You can cater for this as follows:

var renderer = function(params) {
    // add listener
    var selectionChangedCallback = function () {
        // some logic on selection changed here
        console.log('node selected = ' + params.node.isSelected());
    };

    params.node.addEventListener(RowNode.EVENT_ROW_SELECTED, selectionChangedCallback);

    // remove listener on destroy
    params.addRenderedRowEventListener('renderedRowRemoved', function() {
        params.node.removeEventListener(RowNode.EVENT_ROW_SELECTED, selectionChangedCallback);
    }

    return params.value;
}

Row Node IDs

Each Row Node is identified by a unique ID. The ID of the Row Node is used by the grid to identify the row and can be used by your application to look up the Row Node using the grid API getRowNode(id).

Grid Assigned IDs

By default IDs are assigned by the grid when data is set into the grid. The grid uses a sequence starting at 0 and incrementing by 1 to assign row IDs, so if for example there are three rows they will have IDs of 0, 1 and 2. The row ID is constant for as long as the data item lives in the grid.

When using Row Grouping the grid assigns IDs to the row groups as the row groups are created. It uses another sequence again starting at 0 and incrementing by 1 and also prefixes the sequence number with row-group-. So if for example there are three groups they will have IDs of row-group-0, row-group-1 and row-group-2. If the groups are destroyed (eg the user removes the grouping) and recreated again (the user groups by a column) then new ID's will be created e.g. row-group-3, row-group-4 and row-group-5. As with normal rows, the ID's for group rows do not change for as long as the row group exists, however removing and re-adding the grouping will result in new row group ID's even if the row group represents the same group as before.

Application Assigned IDs

In some applications it is useful to tell the grid what IDs to use for particular rows. For example, if you are showing employees, you could configure the grid to use the Employee ID as the row node ID. That would then enable the grid API getRowNode(id) to be called with the Employee ID.

To get the grid to use application assigned IDs, implement the grid callback getRowNodeId(). The callback should return back the ID for a particular piece of row data. For example, the following code snippet returns back the value of attribute 'id' for the supplied data item:

function getRowNodeId(data) {
    return data.id;
}

When providing IDs the following rules must be obeyed:

IDs must be unique
IDs must not change

If the attribute you are intending to use as an ID is either not unique or changes, it will cause unspecified behaviour in the grid. In other words, don't use a field that is not unique or can change.

If using Row Grouping, the grid will always assign IDs for the group level (as there is not a one-to-one mapping with application-supplied row data). The callback getRowNodeId() is only used for non-group level rows.