org.apache.wicket.extensions.ajax.markup.html.autocomplete.AbstractAutoCompleteBehavior.java Source code

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Here is the source code for org.apache.wicket.extensions.ajax.markup.html.autocomplete.AbstractAutoCompleteBehavior.java

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/*
 * 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.ajax.markup.html.autocomplete;

import java.util.Arrays;
import java.util.List;
import java.util.Objects;

import org.apache.wicket.Application;
import org.apache.wicket.Component;
import org.apache.wicket.ajax.AbstractDefaultAjaxBehavior;
import org.apache.wicket.ajax.AjaxRequestTarget;
import org.apache.wicket.ajax.attributes.AjaxRequestAttributes;
import org.apache.wicket.markup.head.HeaderItem;
import org.apache.wicket.markup.head.IHeaderResponse;
import org.apache.wicket.markup.head.IWrappedHeaderItem;
import org.apache.wicket.markup.head.JavaScriptHeaderItem;
import org.apache.wicket.markup.head.OnDomReadyHeaderItem;
import org.apache.wicket.markup.head.ResourceAggregator;
import org.apache.wicket.request.Response;
import org.apache.wicket.request.cycle.RequestCycle;
import org.apache.wicket.request.resource.JavaScriptResourceReference;
import org.apache.wicket.request.resource.ResourceReference;

/**
 * @since 1.2
 * 
 * @author Janne Hietamäki (jannehietamaki)
 */
public abstract class AbstractAutoCompleteBehavior extends AbstractDefaultAjaxBehavior {
    /**
     * A wrapper for the auto-complete DOM-ready event handler.
     * <p>
     * A plain OnDomReadyItem would be aggregated by {@link ResourceAggregator}, possible coming
     * after the event registration of other behaviors.
     */
    private static final class WrappedHeaderItem extends HeaderItem implements IWrappedHeaderItem {
        private final OnDomReadyHeaderItem item;

        private WrappedHeaderItem(OnDomReadyHeaderItem onDomReady) {
            item = onDomReady;
        }

        @Override
        public void render(Response response) {
            item.render(response);
        }

        @Override
        public Iterable<?> getRenderTokens() {
            return item.getRenderTokens();
        }

        @Override
        public HeaderItem getWrapped() {
            return item;
        }

        @Override
        public HeaderItem wrap(HeaderItem item) {
            if (item instanceof OnDomReadyHeaderItem)
                return new WrappedHeaderItem((OnDomReadyHeaderItem) item);
            return item;
        }

        @Override
        public List<HeaderItem> getDependencies() {
            ResourceReference wicketAjaxReference = Application.get().getJavaScriptLibrarySettings()
                    .getWicketAjaxReference();
            return Arrays.<HeaderItem>asList(JavaScriptHeaderItem.forReference(wicketAjaxReference));
        }

        @Override
        public boolean equals(Object o) {
            if (this == o)
                return true;
            if (o == null || getClass() != o.getClass())
                return false;
            WrappedHeaderItem that = (WrappedHeaderItem) o;
            return Objects.equals(item, that.item);
        }

        @Override
        public int hashCode() {
            return Objects.hash(item);
        }
    }

    public static final ResourceReference AUTOCOMPLETE_JS = new JavaScriptResourceReference(
            AutoCompleteBehavior.class, "wicket-autocomplete.js");

    private static final long serialVersionUID = 1L;

    protected AutoCompleteSettings settings;

    /**
     * Constructor that creates an default {@link AutoCompleteSettings}
     */
    public AbstractAutoCompleteBehavior() {
        this(new AutoCompleteSettings());
    }

    /**
     * Constructor
     * 
     * @param settings
     *            settings for the autocomplete list
     */
    public AbstractAutoCompleteBehavior(AutoCompleteSettings settings) {
        if (settings == null) {
            settings = new AutoCompleteSettings();
        }
        this.settings = settings;
    }

    @Override
    public void renderHead(final Component component, final IHeaderResponse response) {
        super.renderHead(component, response);

        renderAutocompleteHead(response);
    }

    /**
     * Render autocomplete init javascript and other head contributions
     * 
     * @param response
     */
    private void renderAutocompleteHead(final IHeaderResponse response) {
        response.render(JavaScriptHeaderItem.forReference(AUTOCOMPLETE_JS));

        String initJS = String.format("new Wicket.AutoComplete(%s, %s);", renderAjaxAttributes(getComponent()),
                constructSettingsJS());

        final OnDomReadyHeaderItem onDomReady = OnDomReadyHeaderItem.forScript(initJS);

        response.render(new WrappedHeaderItem(onDomReady));
    }

    /**
     * 
     * @return JS settings
     */
    protected final String constructSettingsJS() {
        final StringBuilder sb = new StringBuilder();
        sb.append("{preselect: ").append(settings.getPreselect());
        sb.append(",maxHeight: ").append(settings.getMaxHeightInPx());
        sb.append(",adjustInputWidth: ").append(settings.isAdjustInputWidth());
        sb.append(",useSmartPositioning: ").append(settings.getUseSmartPositioning());
        sb.append(",showListOnEmptyInput: ").append(settings.getShowListOnEmptyInput());
        sb.append(",ignoreBordersWhenPositioning: ").append(settings.getIgnoreBordersWhenPositioning());
        sb.append(",showListOnFocusGain: ").append(settings.getShowListOnFocusGain());
        sb.append(",throttleDelay: ").append(settings.getThrottleDelay());
        sb.append(",minInputLength: ").append(settings.getMinInputLength());
        sb.append(",parameterName: '").append(settings.getParameterName()).append('\'');
        sb.append(",showCompleteListOnFocusGain: ").append(settings.getShowCompleteListOnFocusGain());
        if (settings.getCssClassName() != null) {
            sb.append(",className: '").append(settings.getCssClassName()).append('\'');
        }
        sb.append('}');
        return sb.toString();
    }

    /**
     * Callback for the ajax event generated by the javascript. This is where we need to generate
     * our response.
     * 
     * @param input
     *            the input entered so far
     * @param requestCycle
     *            current request cycle
     */
    protected abstract void onRequest(String input, RequestCycle requestCycle);

    @Override
    protected void respond(final AjaxRequestTarget target) {
        final RequestCycle requestCycle = RequestCycle.get();
        final String val = requestCycle.getRequest().getRequestParameters()
                .getParameterValue(settings.getParameterName()).toOptionalString();

        onRequest(val, requestCycle);
    }

    @Override
    protected void updateAjaxAttributes(AjaxRequestAttributes attributes) {
        super.updateAjaxAttributes(attributes);

        attributes.setWicketAjaxResponse(false);
        attributes.setDataType("html");
    }
}