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| <h1>Providing Remove and Delete Functionality</h1> |
| <h2>Difference Between Remove and Delete</h2> |
| <p>A remove feature only eliminates pictogram elements from the pictograms model |
| but the underlying business object (domain model elements) remains in existence. |
| It is basically the opposite of the add feature, which creates a pictogram element |
| for an existing business object.</p> |
| <p>A delete feature additionally eliminates the corresponding business object (domain |
| model elements). It is basically the opposite of the create feature, which creates |
| a business object and the corresponding pictogram element.</p> |
| <p>A delete feature typically calls the remove feature to delete the pictogram element |
| and then deletes the corresponding business object. This is similar to the create |
| feature, which typically creates the business object and then calls the add feature |
| to create the corresponding pictogram element.</p> |
| <h2>Creating a Remove Feature</h2> |
| <p>A remove feature has to implement the interface |
| <a href="../../../javadoc/org/eclipse/graphiti/features/IRemoveFeature.html">IRemoveFeature</a>. |
| Instead of implementing this directly you should extend the available default implementation |
| <a href="../../../javadoc/org/eclipse/graphiti/features/impl/DefaultRemoveFeature.html"> |
| DefaultRemoveFeature</a>.</p> |
| <p>Own implementations of remove features have to be provided by the corresponding |
| feature provider through its |
| <a href="../../../javadoc/org/eclipse/graphiti/features/IFeatureProvider.html#getRemoveFeature(org.eclipse.graphiti.features.context.IRemoveContext)"> |
| getRemoveFeature</a> method. Note, that in most cases it is not necessary to provide |
| an own implementation of the remove feature, because the graphics framework has |
| enough knowledge to provide a good default implementation.</p> |
| <p>To enable the remove of not selectable, so called inner elements, you have to |
| <a href="custom-feature.htm">provide custom features</a>. </p> |
| <h2>Creating a Delete Feature</h2> |
| <p>A delete feature has to implement the interface |
| <a href="../../../javadoc/org/eclipse/graphiti/features/IDeleteFeature.html">IDeleteFeature</a>. |
| Instead of implementing this directly you should extend the available default implementation |
| <a href="../../../javadoc/org/eclipse/graphiti/ui/features/DefaultDeleteFeature.html"> |
| </a>.</p> |
| <p>Own implementations of delete features have to be provided by the corresponding |
| feature provider through its |
| <a href="../../../javadoc/org/eclipse/graphiti/features/IFeatureProvider.html#getDeleteFeature(org.eclipse.graphiti.features.context.IDeleteContext)"> |
| getDeleteFeature</a> method. Note, that in most cases it is not necessary to provide |
| an own implementation of the delete feature, because the graphics framework has |
| enough knowledge to provide a good default implementation.</p> |
| <p>To enable the deletion of not selectable, so called inner elements, you have |
| to <a href="custom-feature.htm">provide custom features</a>.</p> |
| <p> </p> |
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