burrito.client.crud.widgets.LinkedEntityWidget.java Source code

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Here is the source code for burrito.client.crud.widgets.LinkedEntityWidget.java

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/**
 * Copyright 2011 Henric Persson (henric.persson@gmail.com)
 * 
 * Licensed 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 burrito.client.crud.widgets;

import java.util.ArrayList;
import java.util.List;

import burrito.client.crud.labels.CrudMessages;
import burrito.client.widgets.validation.HasValidators;
import burrito.client.widgets.validation.InputFieldValidator;

import com.google.gwt.core.client.GWT;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.user.client.ui.Anchor;
import com.google.gwt.user.client.ui.Composite;
import com.google.gwt.user.client.ui.HorizontalPanel;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.SimplePanel;
import com.google.gwt.user.client.ui.VerticalPanel;

public class LinkedEntityWidget extends Composite implements HasValidators {
    private VerticalPanel wrapper = new VerticalPanel();
    private CrudMessages labels = GWT.create(CrudMessages.class);
    private boolean required;
    private Label validationError = new Label(labels.linkIsRequired());
    private SimplePanel linkViewPlaceholder = new SimplePanel();
    private Anchor add = new Anchor(labels.createNewLink());
    private boolean allowMultiple;
    private List<LinkedEntityValue> added = new ArrayList<LinkedEntityValue>();

    /**
     * Create a new linked entity widget.
     * 
     * @param required
     *            true if at least one link must be specified
     * @param allowMultiple
     *            true if multiple links can be entered. In this case, use
     *            getValues() to fetch a list of links. IF false, use getValue()
     *            to get the only link.
     */
    public LinkedEntityWidget(boolean required, boolean allowMultiple) {
        this.required = required;
        this.allowMultiple = allowMultiple;
        validationError.addStyleName("validationError");
        validationError.setVisible(false);
        wrapper.add(validationError);
        wrapper.add(linkViewPlaceholder);
        add.addClickHandler(new ClickHandler() {

            public void onClick(ClickEvent event) {
                LinkedEntityWidgetPopup popup = new LinkedEntityWidgetPopup(
                        new LinkedEntityWidgetPopup.SaveHandler() {

                            public void saved(String json) {
                                addLink(json);
                            }
                        });
                popup.center();
                popup.show();
            }
        });
        wrapper.add(add);
        initWidget(wrapper);
        addStyleName("k5-LinkedEntityWidget");
    }

    public void addInputFieldValidator(InputFieldValidator validator) {
        throw new UnsupportedOperationException();
    }

    public void setValidationError(String validationError) {
        throw new UnsupportedOperationException();
    }

    public boolean validate() {
        validationError.setVisible(false);
        if (required && getValue() == null) {
            validationError.setVisible(true);
            return false;
        }
        return true;
    }

    /**
     * Gets the json content
     * 
     * @return
     */
    public String getValue() {
        if (added.size() == 0) {
            return null;
        }
        LinkedEntityValue v = added.get(0);
        return v.getJson();
    }

    private void addLink(String json) {
        if (json == null) {
            return;
        }
        if (!allowMultiple) {
            add.setVisible(false);
        }
        final LinkedEntityValue v = new LinkedEntityValue(json);
        added.add(v);

        reloadLinkViews();
    }

    protected void reloadLinkViews() {
        VerticalPanel vp = new VerticalPanel();
        for (final LinkedEntityValue v : added) {
            HorizontalPanel hp = new HorizontalPanel();
            hp.add(v);
            Anchor remove = new Anchor(labels.delete());
            remove.addClickHandler(new ClickHandler() {

                public void onClick(ClickEvent event) {
                    added.remove(v);
                    reloadLinkViews();
                    add.setVisible(true);
                }
            });
            hp.add(remove);
            vp.add(hp);
        }
        linkViewPlaceholder.setWidget(vp);
    }

    /**
     * Sets the only link to be displayed
     * 
     * @param json
     */
    public void setValue(String json) {
        added.clear();
        addLink(json);
    }

    public void setValues(List<String> jsonLinks) {
        added.clear();
        if (jsonLinks == null) {
            return;
        }
        for (String json : jsonLinks) {
            addLink(json);
        }
    }

    public List<String> getValues() {
        List<String> result = new ArrayList<String>();
        for (LinkedEntityValue v : added) {
            result.add(v.getJson());
        }
        return result;
    }

    @Override
    public void highlight() {
        add.setFocus(true);
    }

}