This interface is implemented by the module:ct-grid/DataProviderRowModel so that
GridDataProvider instances are able to communicate data changes as they occur.
GridDataProvider instances are given a reference to any listeners that may be
interested in these events via the module:ct-grid/GridDataProvider#addDataProviderListener method.
Methods
on
This callback is invoked when the state of the container subscription changes.
Parameters:
| Name | Type | Description | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
subject |
string | The container subject |
|||||||||
state |
string | The container state |
|||||||||
sourceState |
object |
additional information provided by the upstream source detailing the reason for this event. The information provided is wholly dependant upon the upstream source implementation. Properties
|
on
This callback is invoked when requested data is first received - before any calls to
module:ct-grid/GridDataProviderListener#onRecordAdded, module:ct-grid/GridDataProviderListener#onRecordMoved
or module:ct-grid/GridDataProviderListener#onSizeChanged
or module:ct-grid/GridDataProviderListener#onStructureChangeComplete are called.
on
This callback is invoked when a request for a data has been initiated (but not a window-adjusting request)
on
This callback is invoked when a request for data fails.
Parameters:
| Name | Type | Description |
|---|---|---|
reason |
string | A brief description of what the error is. The enumeration
|
on
Callback that occurs when one or more of the visible records are replaced by new records and need to be completely redrawn.
This may happen because the user has scrolled the grid display causing different records to be displayed
at the old indices, or when the underlying data changes, such that records are inserted, deleted or
removed. When module:ct-grid/GridDataProvider.PAGING is in use then only records within the
range defined by module:ct-grid/GridDataProvider#setRowRange are reported on.
Parameters:
| Name | Type | Description |
|---|---|---|
recordId |
String | the unique identifier that the |
recordIndex |
int | The row index at which the record exists. |
record |
Map | The map of name value/pairs that contain the record data. |
alternateId |
String | Alternate Identifier (Deprecated, as there is no known need for an alternate id) |
on
Callback that occurs when there are updates to one or more of the visible records.
Parameters:
| Name | Type | Description |
|---|---|---|
recordId |
String | the unique identifier that the |
recordUpdates |
Map | a map containing the updated field data. |
on
Callback that occurs when a visible record is moved to a new location, and remains visible within the current page.
If a record moves out of view, then the data provider does not need to perform any action, since that
record will either be overwritten by some other module:ct-grid/GridDataProviderListener#onRecordAdded
or module:ct-grid/GridDataProviderListener#onRecordMoved invocation, or will be effectively
removed by an module:ct-grid/GridDataProviderListener#onSizeChanged invocation with a smaller
size that means that some of the previous row indices no longer exist at all.
Parameters:
| Name | Type | Description |
|---|---|---|
recordId |
String | the unique identifier that the |
newIndex |
int | The row index at which the record will now exist. |
on
Callback that occurs when a visible record is removed/deleted.
If a record is deleted from the source of the data provider's data then calling this should clean up any reference to the now defunct row.
Parameters:
| Name | Type | Description |
|---|---|---|
recordId |
String | the unique identifier that the |
on
Callback that occurs when the number of underlying records available changes.
This has no relation to the number of records that are being displayed, and is only a measure of the available records.
Parameters:
| Name | Type | Description |
|---|---|---|
newSize |
int | the total number of available records. |
oldSize |
int | the previous total number of available records. |
on
Callback that occurs when, for some reason, the data provider wishes to change the start index that the view is currently looking at.
This event allows the data provider to adjust the start index that the view has previously set using
module:ct-grid/GridDataProvider#setRowRange. There are a number of reasons a data provider might
wish to do this:
- The number of available records is updated to be smaller than the currently displayed start index, meaning that the view would otherwise now display zero records.
- The user wishes to track the current record they are looking at as new records appear at the top of the list.
- If the user is already scrolled to the top, then they wish to stay at the top even when new records appear above the previous top one.
- If the user is already scrolled to the bottom, then they wish to stay at the bottom even when new records appear below the previous bottom one.
All of these scrolling strategies could be, and probably should be, implemented within the
module:ct-grid/DataProviderRowModel, but for the purposes of efficiency it is also useful to
allow them to be implemented directly within data provider, since this allows the number of round trips for
data to be reduced.
Parameters:
| Name | Type | Description |
|---|---|---|
newStartIndex |
int |
on
Callback that occurs after a number of invocations to module:ct-grid/GridDataProviderListener#onRecordAdded,
module:ct-grid/GridDataProviderListener#onRecordMoved or
module:ct-grid/GridDataProviderListener#onSizeChanged have been made, informing the
module:ct-grid/DataProviderRowModel, and underlying module:ct-grid/GridView that
all updates can now be rendered.
Allowing updates to be batched like this allows the module:ct-grid/GridView class to perform
more efficiently since it is able to use a single call to innerHTML to re-render a changed
grid, rather than making lots of expensive, individual DOM calls.