package org.argeo.cms.ui.eclipse.forms; /** * Classes that implement this interface can be added to the managed form and * take part in the form life cycle. The part is initialized with the form and * will be asked to accept focus. The part can receive form input and can elect * to do something according to it (for example, select an object that matches * the input). *
* The form part has two 'out of sync' states in respect to the model(s) that * feed the form: dirty and stale. When a part is dirty, it * means that the user interacted with it and now its widgets contain state that * is newer than the model. In order to sync up with the model, 'commit' needs * to be called. In contrast, the model can change 'under' the form (as a result * of some actions outside the form), resulting in data in the model being * 'newer' than the content presented in the form. A 'stale' form part is * brought in sync with the model by calling 'refresh'. The part is responsible * for notifying the form when one of these states change in the part. The form * reserves the right to handle this notification in the most appropriate way * for the situation (for example, if the form is in a page of the multi-page * editor, it may do nothing for stale parts if the page is currently not * showing). *
* When the form is disposed, each registered part is disposed as well. Parts
* are responsible for releasing any system resources they created and for
* removing themselves as listeners from all event providers.
*
* @see IManagedForm
* @since 1.0
*
*/
public interface IFormPart {
/**
* Initializes the part.
*
* @param form
* the managed form that manages the part
*/
void initialize(IManagedForm form);
/**
* Disposes the part allowing it to release allocated resources.
*/
void dispose();
/**
* Returns true if the part has been modified with respect to the data
* loaded from the model.
*
* @return true if the part has been modified with respect to the data
* loaded from the model
*/
boolean isDirty();
/**
* If part is displaying information loaded from a model, this method
* instructs it to commit the new (modified) data back into the model.
*
* @param onSave
* indicates if commit is called during 'save' operation or for
* some other reason (for example, if form is contained in a
* wizard or a multi-page editor and the user is about to leave
* the page).
*/
void commit(boolean onSave);
/**
* Notifies the part that an object has been set as overall form's input.
* The part can elect to react by revealing or selecting the object, or do
* nothing if not applicable.
*
* @return true
if the part has selected and revealed the
* input object, false
otherwise.
*/
boolean setFormInput(Object input);
/**
* Instructs form part to transfer focus to the widget that should has focus
* in that part. The method can do nothing (if it has no widgets capable of
* accepting focus).
*/
void setFocus();
/**
* Tests whether the form part is stale and needs refreshing. Parts can
* receive notification from models that will make their content stale, but
* may need to delay refreshing to improve performance (for example, there
* is no need to immediately refresh a part on a form that is current on a
* hidden page).
*
* It is important to differentiate 'stale' and 'dirty' states. Part is
* 'dirty' if user interacted with its editable widgets and changed the
* values. In contrast, part is 'stale' when the data it presents in the
* widgets has been changed in the model without direct user interaction.
*
* @return true
if the part needs refreshing,
* false
otherwise.
*/
boolean isStale();
/**
* Refreshes the part completely from the information freshly obtained from
* the model. The method will not be called if the part is not stale.
* Otherwise, the part is responsible for clearing the 'stale' flag after
* refreshing itself.
*/
void refresh();
}