com.googlecode.wicket.jquery.ui.interaction.draggable.DraggableBehavior.java Source code

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Here is the source code for com.googlecode.wicket.jquery.ui.interaction.draggable.DraggableBehavior.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 com.googlecode.wicket.jquery.ui.interaction.draggable;

import org.apache.wicket.Component;
import org.apache.wicket.WicketRuntimeException;
import org.apache.wicket.ajax.AjaxRequestTarget;
import org.apache.wicket.ajax.attributes.CallbackParameter;
import org.apache.wicket.util.visit.IVisit;
import org.apache.wicket.util.visit.IVisitor;

import com.googlecode.wicket.jquery.core.JQueryBehavior;
import com.googlecode.wicket.jquery.core.JQueryEvent;
import com.googlecode.wicket.jquery.core.Options;
import com.googlecode.wicket.jquery.core.ajax.IJQueryAjaxAware;
import com.googlecode.wicket.jquery.core.ajax.JQueryAjaxBehavior;
import com.googlecode.wicket.jquery.ui.interaction.droppable.DroppableBehavior;

/**
 * Provides a jQuery draggable behavior<br/>
 * <b>Warning:</b> not thread-safe: the instance of this behavior should only be used once
 *
 * @author Sebastien Briquet - sebfz1
 */
public abstract class DraggableBehavior extends JQueryBehavior implements IJQueryAjaxAware, IDraggableListener {
    private static final long serialVersionUID = 1L;
    private static final String METHOD = "draggable";

    private JQueryAjaxBehavior onDragStartBehavior;
    private JQueryAjaxBehavior onDragStopBehavior = null;
    private Component component = null;

    /**
     * Constructor
     * @param selector the html selector (ie: "#myId")
     */
    public DraggableBehavior(String selector) {
        this(selector, new Options());
    }

    /**
     * Constructor
     * @param selector the html selector (ie: "#myId")
     * @param options the {@link Options}
     */
    public DraggableBehavior(String selector, Options options) {
        super(selector, METHOD, options);
    }

    // Methods //
    @Override
    public void bind(Component component) {
        super.bind(component);

        if (this.component != null) {
            throw new WicketRuntimeException("Behavior is already bound to another component.");
        }

        this.component = component; //warning, not thread-safe: the instance of this behavior should only be used once
        this.component.add(this.onDragStartBehavior = this.newOnDragStartBehavior());

        // these events are not enabled by default to prevent unnecessary server round-trips.
        if (this.isStopEventEnabled()) {
            this.component.add(this.onDragStopBehavior = this.newOnDragStopBehavior());
        }

    }

    // Events //
    @Override
    public void onConfigure(Component component) {
        super.onConfigure(component);

        this.setOption("start", this.onDragStartBehavior.getCallbackFunction());

        if (this.onDragStopBehavior != null) {
            this.setOption("stop", this.onDragStopBehavior.getCallbackFunction());
        }
    }

    @Override
    public void onAjax(AjaxRequestTarget target, JQueryEvent event) {
        if (event instanceof DragStartEvent) {
            this.onDragStart(target);

            // register to all DroppableBehavior(s) //
            target.getPage().visitChildren(this.newDroppableBehaviorVisitor());
        }

        else if (event instanceof DragStopEvent) {
            this.onDragStop(target);
        }
    }

    // Factories //
    /**
     * Gets a new {@link DroppableBehavior} visitor.<br/>
     * This {@link IVisitor} is responsible for register the {@link DroppableBehavior} to this {@link DraggableBehavior}
     *
     * @return a {@link IVisitor}
     */
    private IVisitor<Component, ?> newDroppableBehaviorVisitor() {
        return new IVisitor<Component, Void>() {

            @Override
            public void component(Component component, IVisit<Void> visit) {
                for (DroppableBehavior behavior : component.getBehaviors(DroppableBehavior.class)) {
                    behavior.setDraggable(DraggableBehavior.this.component);
                }
            }
        };
    }

    /**
     * Gets a new {@link JQueryAjaxBehavior} that will be called on 'start' javascript event
     * @return the {@link JQueryAjaxBehavior}
     */
    protected JQueryAjaxBehavior newOnDragStartBehavior() {
        return new JQueryAjaxBehavior(this) {

            private static final long serialVersionUID = 1L;

            @Override
            protected CallbackParameter[] getCallbackParameters() {
                return new CallbackParameter[] { CallbackParameter.context("event"),
                        CallbackParameter.context("ui") };
            }

            @Override
            protected JQueryEvent newEvent() {
                return new DragStartEvent();
            }
        };
    }

    /**
     * Gets a new {@link JQueryAjaxBehavior} that will be called on 'stop' javascript event
     * @return the {@link JQueryAjaxBehavior}
     */
    protected JQueryAjaxBehavior newOnDragStopBehavior() {
        return new JQueryAjaxBehavior(this) {

            private static final long serialVersionUID = 1L;

            @Override
            protected CallbackParameter[] getCallbackParameters() {
                return new CallbackParameter[] { CallbackParameter.context("event"),
                        CallbackParameter.context("ui") };
            }

            @Override
            protected JQueryEvent newEvent() {
                return new DragStopEvent();
            }
        };
    }

    // Events classes //
    /**
     * Provides an event object that will be broadcasted by the {@link JQueryAjaxBehavior} 'start' callback
     */
    protected static class DragStartEvent extends JQueryEvent {
    }

    /**
     * Provides an event object that will be broadcasted by the {@link JQueryAjaxBehavior} 'stop' callback
     */
    protected static class DragStopEvent extends JQueryEvent {
    }
}