Package com.smartgwt.client.widgets.tree.events

# Interface DataChangedHandler

All Superinterfaces:
  `EventHandler`

public interface DataChangedHandler extends EventHandler

- ## Method Summary

  Modifier and Type
  Method
  Description
  `void`
  `onDataChanged(DataChangedEvent event)`
  Notification method fired when the TreeGrid's data changes, for any reason.

- ## Method Details

  - ### onDataChanged

    void onDataChanged(DataChangedEvent event)
    Notification method fired when the TreeGrid's data changes, for any reason.

    Examples of why data changed might be:

    - a call to `addData()`, `updateData()`, or `removeData()`
    - `DataSource` updates from the server for `ResultTree` data (triggered by record editing, etc.)
    - fetches arriving back from the server for `ResultTree` data
    - programmatic changes to `Tree` data if made through APIs such as `Tree.add()`, `Tree.remove()`, etc.
    - cache invalidation
    - filtering
    Calling `setData()` doesn't call this notification directly, but it may fire if one of the above listed events is triggered (e.g. a server fetch for `ResultTree` data).

    Note that the `operationType` parameter is optional and will be passed and contain the operation (e.g. "update") if this notification was triggered by a fetch, an `addData()`, `updateData()`, or `removeData()`, or a `DataSource` update for `ResultTree` data (the first three reasons listed above) but otherwise will be null.

    Parameters:
      `event` - the event