Fundamentals > Fundamentals > User Interface Basics > Chains and Surface Sets > Chains > To Append or Exclude Items from a Chain
To Append or Exclude Items from a Chain
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This topic discusses chain modification while working inside of a tool and using the Chain dialog box. If you want to modify a chain while working outside of a tool, you can use the SHIFT key to clear the selection of individual items from the ends of a chain or use the CTRL key to remove an entire chain from the selection set. Refer to About Selection under See Also for more information about clearing a selection.
You can append items or exclude items in rule-based chains. However, all tools may not support the appending and excluding of items.
1. Construct the chain and open the tool in which to work with the chain, or select a feature that contains an existing chain that you want to modify and click Edit Definition.
2. Locate the Detail collector that contains the chain that you want to modify. Detail collectors are located on the panel. Note that you cannot use the Summary collector (located on the dialog bar) to modify a chain.
3. Click Details. Creo Parametric pauses the tool, opens the Chain dialog box, and displays the attributes for the chain.
4. If the panel Detail collector contains more than one chain, select the chain to modify from the chain list in the Chain dialog box. The chain attributes are displayed.
5. Click the Options tab.
6. Click in the Appended or Excluded collector to append items or exclude items, respectively. Clicking the collector activates the collector. Notice that you can also use the Appended Items or Excluded Items shortcut menu command from inside the graphics window to activate this collector.
7. Hold down the CTRL key and from the graphics window, select one or more edges or curves from your model to append to or remove from the chain. The Appended collector does not allow you to select an excluded edge or curve. Similarly, the Excluded collector does not allow you to select an appended edge or curve.
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Creo Parametric dynamically validates the chain you are creating or editing. If the chain is valid the Dynamic validation box is automatically selected. When dynamic validation is enabled, adding new references to the active collector or removing references from the active collector does not make the active chain invalid.
If the chain is invalid the Dynamic validation box is automatically cleared. When dynamic validation is disabled, you can add new references to the active collector or remove references from the active collector without restrictions. However, this may make the active chain invalid. If the chain becomes invalid then the Dynamic validation box becomes unavailable.
You can disable dynamic validation at any time.
8. Click OK. Creo Parametric saves the changes, closes the Chain dialog box, and resumes the tool.
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Notice that as you modify a chain in the Chain dialog box, Creo Parametric dynamically displays the changes in the graphics window.
To clear references in the active collector, click Remove or Remove All on the shortcut menu that appears when you right-click in the collector. Alternatively, click Clear on the shortcut menu that appears when you right-click in the graphics window.
To easily locate references in the Chain dialog box, place your pointer over the reference in a collector. Creo Parametric dynamically highlights the reference on the model.