org.apache.wicket.extensions.wizard.IWizardModel Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of org.ops4j.pax.wicket.service Show documentation
Pax Wicket Service is an OSGi extension of the Wicket framework, allowing for dynamic loading and unloading of Wicket components and pageSources.
There is a newer version: 5.0.0
Show newest version
/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.wicket.extensions.wizard;

import java.util.Iterator;

import org.apache.wicket.IClusterable;

/**
 * This interface defines the model for wizards. This model knows about the wizard's steps and the
 * transitions between them, and it holds a reference to the currently active step. It might
 * function as a generic state holder for the wizard too, though you might find it more convenient
 * to use the wizard component itself for that, or even an external model.
 * 
 * 
 * {@link IWizardModelListener wizard model listeners} can be registered to be notified of important
 * events (changing the active step) using the
 * {@link #addListener(IWizardModelListener) add listener} method.
 * 
 * 
 * 
 * Typically, you would use {@link WizardModel the default implementation of this interface}, but
 * if you need to do more sophisticated stuff, like branching etc, you can consider creating your
 * own implementation. In that case, it is recommended you start by extending from
 * {@link AbstractWizardModel}.
 * 
 * 
 * 
 * Swing Wizard Framework served as a valuable
 * source of inspiration.
 * 
 * 
 * @see AbstractWizardModel
 * @see WizardModel
 * 
 * @author Eelco Hillenius
 */
public interface IWizardModel extends IClusterable
{
	/**
	 * Adds a wizard model listener.
	 * 
	 * @param listener
	 *            The wizard model listener to add
	 */
	void addListener(IWizardModelListener listener);

	/**
	 * Cancels further processing. Implementations may clean up and reset the model. Implementations
	 * should notify the registered {@link IWizardModelListener#onCancel() model listeners}.
	 */
	void cancel();

	/**
	 * Instructs the wizard to finish succesfully. Typically, implementations check whether this
	 * option is available at all. Implementations may clean up and reset the model. Implementations
	 * should notify the registered {@link IWizardModelListener#onFinish() model listeners}.
	 */
	void finish();

	/**
	 * Gets the current active step the wizard should display.
	 * 
	 * @return the active step.
	 */
	IWizardStep getActiveStep();

	/**
	 * Gets whether the cancel button should be displayed.
	 * 
	 * @return True if the cancel button should be displayed
	 */
	boolean isCancelVisible();

	/**
	 * Checks if the last button should be enabled.
	 * 
	 * @return true if the last button should be enabled, false otherwise.
	 * @see #isLastVisible
	 */
	boolean isLastAvailable();

	/**
	 * Gets whether the specified step is the last step in the wizard.
	 * 
	 * @param step
	 *            the step to check
	 * @return True if its the final step in the wizard, false< otherwise.
	 */
	boolean isLastStep(IWizardStep step);

	/**
	 * Gets whether the last button should be displayed. This method should only return true if the
	 * {@link #isLastAvailable} will return true at any point. Returning false will prevent the last
	 * button from appearing on the wizard at all.
	 * 
	 * @return True if the last button should be displayed, False otherwise.
	 */
	boolean isLastVisible();

	/**
	 * Gets whether the next button should be enabled.
	 * 
	 * @return True if the next button should be enabled, false otherwise.
	 */
	boolean isNextAvailable();

	/**
	 * Gets whether the previous button should be enabled.
	 * 
	 * @return True if the previous button should be enabled, false otherwise.
	 */
	boolean isPreviousAvailable();

	/**
	 * Takes the model to the last step in the wizard. This method must only be called if
	 * {@link #isLastAvailable} returns true. Implementors should notify
	 * {@link IWizardModelListener listeners} through calling
	 * {@link IWizardModelListener#onActiveStepChanged(IWizardStep)}.
	 */
	void last();

	/**
	 * Increments the model to the next step. This method must only be called if
	 * {@link #isNextAvailable} returns true. Implementors should notify
	 * {@link IWizardModelListener listeners} through calling
	 * {@link IWizardModelListener#onActiveStepChanged(IWizardStep)}.
	 */
	void next();

	/**
	 * Takes the model to the previous step.This method must only be called if
	 * {@link #isPreviousAvailable} returns true. Implementors should notify
	 * {@link IWizardModelListener listeners} through calling
	 * {@link IWizardModelListener#onActiveStepChanged(IWizardStep)}.
	 */
	void previous();

	/**
	 * Removes a wizard model listener.
	 * 
	 * @param listener
	 *            The listener to remove
	 */
	void removeListener(IWizardModelListener listener);

	/**
	 * Resets the model, setting it to the first step. Implementors should notify
	 * {@link IWizardModelListener listeners} through calling
	 * {@link IWizardModelListener#onActiveStepChanged(IWizardStep)}.
	 */
	void reset();

	/**
	 * Returns an iterator over all the steps in the model. The iteration order is not guaranteed to
	 * the be the order of traversal. This is an optional operation; dynamic models can just return
	 * null, and should call init the first time a step is encountered right before rendering it.
	 * 
	 * @return an iterator over all the steps of the model or null if the wizard model is not static
	 */
	Iterator stepIterator();
}