About Custom Selection Action in Visualization Tab of BOM Transformer
In the Visualization tab of BOM Transformer, click 
Selection Assistance > to enable the Custom Selection action. When you enable the Custom Selectionaction, and select a part in the visualization pane, by default, the corresponding part is selected in the tree structure. An administrator can customize the selection criteria for Custom Selection action in upstream and downstream views of BOM Transformer by configuring properties in associativity.properties.xconf.
Selection Assistance > to enable the Custom Selection action. When you enable the Custom Selectionaction, and select a part in the visualization pane, by default, the corresponding part is selected in the tree structure. An administrator can customize the selection criteria for Custom Selection action in upstream and downstream views of BOM Transformer by configuring properties in associativity.properties.xconf.• For upstream view, configure the com.ptc.windchill.associativity.upstreamCustomVizSelectionObjectTypes property to specify valid values.
• For downstream view, configure the com.ptc.windchill.associativity.downstreamCustomVizSelectionObjectTypes property to specify valid values.
These properties are found inassociativity.properties.xconf located at <Windchill>\codebase\com\ptc\core\foundation\associativity\xconfs.
You can specify the following values in the properties:
• Object types- For example, WTPart1. Specify multiple values using a semicolon separator.
• Object Type Name, Attribute Name, and Attribute value- For example, wt.part.WTPart|Source|Make. Specify these values using a pipe separator. The attribute value should be of type string.
• A combination of the first two entities- For example, WTPart1;wt.part.WTPart2|Source|Make.
Configuring Custom Selection properties
• When specifying the object types:
<AddToProperty name="com.ptc.windchill.associativity.upstreamCustomVizSelectionObjectTypes" value="wt.part.WTPart1; wt.part.WTPart2"/>
• When specifying the object types with attribute type and attribute value:
<AddToProperty name="com.ptc.windchill.associativity.upstreamCustomVizSelectionObjectTypes" value="wt.part.WTPart|Source|Make"/>
• When specifying a combination, configure the property as follows:
<AddToProperty name="com.ptc.windchill.associativity.upstreamCustomVizSelectionObjectTypes" value=" WTPart1;wt.part.WTPart2|Source|Make"/>
Restart Windchill server after configuring the property for the changes to take effect.
After configuring the property, when you enable the Custom Selection action and select a part in the Visualization tab, the tree structure is traversed upward. The first level child part of the parts that satisfy the criteria set in the property is selected.
Consider the following points related with the Custom Selection action:
• In BOM Transformer, when you select Custom Selection, the Select Parent and Select First Level Assembly actions are disabled.
• If you selected the Custom Selection action before closing a BOM Transformer session, the same action will be selected by default when you open a new BOM Transformer session.
• Before using the Custom Selection action, you must enable the 
> action.
> action.When multiple values are specified in the com.ptc.windchill.associativity.upstreamCustomVizSelectionObjectTypes and com.ptc.windchill.associativity.downstreamCustomVizSelectionObjectTypes properties, traversing stops as soon as the part that satisfies one of the set values is found. For example, for the following property definition, traversing through the structure stops when a part satisfies the WTPart1 value is found:<AddToProperty name="com.ptc.windchill.associativity.upstreamCustomVizSelectionObjectTypes" value=" WTPart1;wt.part.WTPart2|Source|Make"/>
For more details, refer the following: