Generating a Data Tree (Magic xpa 4.x)
The following runtime behavior occurs when an Online task containing a Tree control on the task’s main form is opened:
-
The data view range is calculated.
-
If the root value exists, the runtime engine displays the root value as the top parent node and fetches the record from the database.
-
The initial expand level for the tree is determined by the value selected for the Auto Expand or Single Expand properties.
-
When the Node Preload property is set to Yes, the runtime engine loads the data of all the records in the task data view. If No is selected, the runtime engine only loads the data of expanded records. Note that this property specifies how the data is loaded at runtime.
-
For each retrieved record, a new node is added to the tree with the relevant node’s GUI data. Steps 3 and 4 will be repeated for all the records specified by the Auto Expand property.
