Navigating in the Data Tree (Magic xpa 4.x)

The runtime engine always points to the current node of the data view, represented by the current node in focus. When you move to another node, the GUI layer instructs the runtime engine to update the current node.

If the parent node is expanded for the first time, the GUI layer sends a request to the runtime engine to retrieve the records for nodes associated with the expanded parent node. If the parent node was expanded previously, the GUI layer displays the expanded node level, but does not send a request to the runtime engine.

If an expanded parent node is collapsed, the GUI layer displays the closed node, but does not send a request to the runtime engine. If the selected node is part of the collapsed parent node, the GUI layer displays the parent node as selected and sends a request to the runtime engine to change the current record.

The runtime engine remains parked on the selected node even when the focus moves from the data tree.