JaboxFeedbackPanel.java

package org.jabox.webapp.panels;

import java.io.Serializable;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

import org.apache.wicket.AttributeModifier;
import org.apache.wicket.Component;
import org.apache.wicket.feedback.FeedbackMessage;
import org.apache.wicket.feedback.FeedbackMessagesModel;
import org.apache.wicket.feedback.IFeedback;
import org.apache.wicket.feedback.IFeedbackMessageFilter;
import org.apache.wicket.markup.html.WebMarkupContainer;
import org.apache.wicket.markup.html.basic.Label;
import org.apache.wicket.markup.html.list.ListItem;
import org.apache.wicket.markup.html.list.ListView;
import org.apache.wicket.markup.html.panel.Panel;
import org.apache.wicket.model.IModel;
import org.apache.wicket.model.Model;

public class JaboxFeedbackPanel extends Panel implements IFeedback {
    /**
     * List for messages.
     */
    private final class MessageListView extends ListView<FeedbackMessage> {
        private static final long serialVersionUID = 1L;

        /**
         * @see org.apache.wicket.Component#Component(String)
         */
        public MessageListView(final String id) {
            super(id);
            setDefaultModel(newFeedbackMessagesModel());
        }

        @Override
        protected void populateItem(
                final ListItem<FeedbackMessage> listItem) {
            final FeedbackMessage message = listItem.getModelObject();
            message.markRendered();
            final IModel<String> replacementModel = new Model<String>() {
                private static final long serialVersionUID = 1L;

                /**
                 * Returns feedbackPanel + the message level, eg
                 * 'feedbackPanelERROR'. This is used as the class of the li /
                 * span elements.
                 * 
                 * @see org.apache.wicket.model.IModel#getObject()
                 */
                @Override
                public String getObject() {
                    return getCSSClass(message);
                }
            };

            final Component label =
                newMessageDisplayComponent("message", message);
            final AttributeModifier levelModifier =
                new AttributeModifier("class", replacementModel);
            // label.add(levelModifier);
            listItem.add(levelModifier);
            listItem.add(label);
        }
    }

    private static final long serialVersionUID = 1L;

    /** Message view */
    private final MessageListView messageListView;

    /**
     * @see org.apache.wicket.Component#Component(String)
     */
    public JaboxFeedbackPanel(final String id) {
        this(id, null);
    }

    /**
     * @see org.apache.wicket.Component#Component(String)
     * @param id
     * @param filter
     */
    public JaboxFeedbackPanel(final String id,
            final IFeedbackMessageFilter filter) {
        super(id);
        WebMarkupContainer messagesContainer =
            new WebMarkupContainer("feedbackul") {
                private static final long serialVersionUID = 1L;

                @Override
                public boolean isVisible() {
                    return anyMessage();
                }
            };
        add(messagesContainer);
        messageListView = new MessageListView("messages");
        messageListView.setVersioned(false);
        messagesContainer.add(messageListView);

        if (filter != null) {
            setFilter(filter);
        }
    }

    /**
     * Search messages that this panel will render, and see if there is any
     * message of level ERROR or up. This is a convenience method; same as
     * calling 'anyMessage(FeedbackMessage.ERROR)'.
     * 
     * @return whether there is any message for this panel of level ERROR or up
     */
    public final boolean anyErrorMessage() {
        return anyMessage(FeedbackMessage.ERROR);
    }

    /**
     * Search messages that this panel will render, and see if there is any
     * message.
     * 
     * @return whether there is any message for this panel
     */
    public final boolean anyMessage() {
        return anyMessage(FeedbackMessage.UNDEFINED);
    }

    /**
     * Search messages that this panel will render, and see if there is any
     * message of the given level.
     * 
     * @param level
     *            the level, see FeedbackMessage
     * @return whether there is any message for this panel of the given level
     */
    public final boolean anyMessage(final int level) {
        List<FeedbackMessage> msgs = getCurrentMessages();

        for (FeedbackMessage msg : msgs) {
            if (msg.isLevel(level)) {
                return true;
            }
        }

        return false;
    }

    /**
     * @return Model for feedback messages on which you can install filters and
     *         other properties
     */
    public final FeedbackMessagesModel getFeedbackMessagesModel() {
        return (FeedbackMessagesModel) messageListView.getDefaultModel();
    }

    /**
     * @return The current message filter
     */
    public final IFeedbackMessageFilter getFilter() {
        return getFeedbackMessagesModel().getFilter();
    }

    /**
     * @return The current sorting comparator
     */
    public final Comparator<FeedbackMessage> getSortingComparator() {
        return getFeedbackMessagesModel().getSortingComparator();
    }

    /**
     * @see org.apache.wicket.Component#isVersioned()
     */
    @Override
    public boolean isVersioned() {
        return false;
    }

    /**
     * Sets a filter to use on the feedback messages model
     * 
     * @param filter
     *            The message filter to install on the feedback messages model
     * @return FeedbackPanel this.
     */
    public final JaboxFeedbackPanel setFilter(
            final IFeedbackMessageFilter filter) {
        getFeedbackMessagesModel().setFilter(filter);
        return this;
    }

    /**
     * @param maxMessages
     *            The maximum number of feedback messages that this feedback
     *            panel should show at one time
     * @return FeedbackPanel this.
     */
    public final JaboxFeedbackPanel setMaxMessages(final int maxMessages) {
        messageListView.setViewSize(maxMessages);
        return this;
    }

    /**
     * Sets the comparator used for sorting the messages.
     * 
     * @param sortingComparator
     *            comparator used for sorting the messages.
     * @return FeedbackPanel this.
     */
    public final JaboxFeedbackPanel setSortingComparator(
            final Comparator<FeedbackMessage> sortingComparator) {
        getFeedbackMessagesModel().setSortingComparator(sortingComparator);
        return this;
    }

    /**
     * Gets the css class for the given message.
     * 
     * @param message
     *            the message
     * @return the css class; by default, this returns feedbackPanel + the
     *         message level, eg 'feedbackPanelERROR', but you can override this
     *         method to provide your own
     */
    protected String getCSSClass(final FeedbackMessage message) {
        return "alert alert-" + message.getLevelAsString().toLowerCase();
    }

    /**
     * Gets the currently collected messages for this panel.
     * 
     * @return the currently collected messages for this panel, possibly empty
     */
    protected final List<FeedbackMessage> getCurrentMessages() {
        final List<FeedbackMessage> messages =
            messageListView.getModelObject();
        return Collections.unmodifiableList(messages);
    }

    /**
     * Gets a new instance of FeedbackMessagesModel to use.
     * 
     * @return Instance of FeedbackMessagesModel to use
     */
    protected FeedbackMessagesModel newFeedbackMessagesModel() {
        return new FeedbackMessagesModel(this);
    }

    /**
     * Generates a component that is used to display the message inside the
     * feedback panel. This component must handle being attached to
     * <code>span</code> tags. By default a {@link Label} is used. Note that the
     * created component is expected to respect feedback panel's
     * {@link #getEscapeModelStrings()} value
     * 
     * @param id
     *            parent id
     * @param message
     *            feedback message
     * @return component used to display the message
     */
    protected Component newMessageDisplayComponent(final String id,
            final FeedbackMessage message) {
        Serializable serializable = message.getMessage();
        Label label =
            new Label(id, (serializable == null) ? ""
                    : serializable.toString());
        label.setEscapeModelStrings(JaboxFeedbackPanel.this
            .getEscapeModelStrings());
        return label;
    }
}