Java tutorial
/* * 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.markup.html.panel; 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.model.IModel; /** * A panel that displays {@link org.apache.wicket.feedback.FeedbackMessage}s in a list view. The * maximum number of messages to show can be set with setMaxMessages(). * * @see org.apache.wicket.feedback.FeedbackMessage * @see org.apache.wicket.feedback.FeedbackMessages * @author Jonathan Locke * @author Eelco Hillenius */ public class FeedbackPanel 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 IModel<FeedbackMessage> getListItemModel( final IModel<? extends List<FeedbackMessage>> listViewModel, final int index) { return new IModel<FeedbackMessage>() { private static final long serialVersionUID = 1L; /** * WICKET-4258 Feedback messages might be cleared already. * * @see org.apache.wicket.settings.ApplicationSettings#setFeedbackMessageCleanupFilter(org.apache.wicket.feedback.IFeedbackMessageFilter) */ @Override public FeedbackMessage getObject() { if (index >= listViewModel.getObject().size()) { return null; } else { return listViewModel.getObject().get(index); } } }; } @Override protected void populateItem(final ListItem<FeedbackMessage> listItem) { final FeedbackMessage message = listItem.getModelObject(); message.markRendered(); final Component label = newMessageDisplayComponent("message", message); final AttributeModifier levelModifier = AttributeModifier.append("class", getCSSClass(message)); listItem.add(levelModifier); listItem.add(label); } /** * WICKET-4831 - Overridable to allow customization * * @param index * The index of the item * @param itemModel * object in the list that the item represents * @return */ @Override protected ListItem<FeedbackMessage> newItem(int index, IModel<FeedbackMessage> itemModel) { return FeedbackPanel.this.newMessageItem(index, itemModel); } } private static final long serialVersionUID = 1L; /** Message view */ private final MessageListView messageListView; /** * @see org.apache.wicket.Component#Component(String) */ public FeedbackPanel(final String id) { this(id, null); } /** * @see org.apache.wicket.Component#Component(String) * * @param id * @param filter */ public FeedbackPanel(final String id, IFeedbackMessageFilter filter) { super(id); WebMarkupContainer messagesContainer = new WebMarkupContainer("feedbackul") { private static final long serialVersionUID = 1L; @Override protected void onConfigure() { super.onConfigure(); setVisible(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(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 FeedbackPanel setFilter(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 FeedbackPanel setMaxMessages(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 FeedbackPanel setSortingComparator(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) { String cssClass; switch (message.getLevel()) { case FeedbackMessage.UNDEFINED: cssClass = getString(FeedbackMessage.UNDEFINED_CSS_CLASS_KEY); break; case FeedbackMessage.DEBUG: cssClass = getString(FeedbackMessage.DEBUG_CSS_CLASS_KEY); break; case FeedbackMessage.INFO: cssClass = getString(FeedbackMessage.INFO_CSS_CLASS_KEY); break; case FeedbackMessage.SUCCESS: cssClass = getString(FeedbackMessage.SUCCESS_CSS_CLASS_KEY); break; case FeedbackMessage.WARNING: cssClass = getString(FeedbackMessage.WARNING_CSS_CLASS_KEY); break; case FeedbackMessage.ERROR: cssClass = getString(FeedbackMessage.ERROR_CSS_CLASS_KEY); break; case FeedbackMessage.FATAL: cssClass = getString(FeedbackMessage.FATAL_CSS_CLASS_KEY); break; default: cssClass = "feedbackPanel" + message.getLevelAsString(); } return cssClass; } /** * 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<? extends 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(String id, FeedbackMessage message) { Serializable rawMessage = message.getMessage(); Label label = new Label(id, rawMessage); label.setEscapeModelStrings(FeedbackPanel.this.getEscapeModelStrings()); return label; } /** * Allows to define the listItem to use in the feedback's message list. * * @param index * The index of the item * @param itemModel * The model object of the item * @return Container that holds components of the feedback MessageListView. */ protected ListItem<FeedbackMessage> newMessageItem(int index, IModel<FeedbackMessage> itemModel) { return new ListItem<>(index, itemModel); } }