com.bearsoft.gwt.ui.RadioGroup.java Source code

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Here is the source code for com.bearsoft.gwt.ui.RadioGroup.java

Source

/*
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package com.bearsoft.gwt.ui;

import com.google.gwt.event.logical.shared.ValueChangeEvent;
import com.google.gwt.event.logical.shared.ValueChangeHandler;
import com.google.gwt.event.shared.EventHandler;
import com.google.gwt.event.shared.GwtEvent;
import com.google.gwt.event.shared.HandlerManager;
import com.google.gwt.event.shared.HandlerRegistration;
import com.google.gwt.user.client.DOM;
import com.google.gwt.user.client.ui.HasName;
import com.google.gwt.user.client.ui.HasValue;
import com.google.gwt.user.client.ui.UIObject;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * 
 * @author mg
 */
public class RadioGroup extends UIObject implements ValueChangeHandler<Boolean> {

    protected Map<HasValue<Boolean>, HandlerRegistration> groupedHandlers = new HashMap<>();
    protected List<HasValue<Boolean>> grouped = new ArrayList<>();

    protected String groupName = "group-" + DOM.createUniqueId();
    //
    private HandlerManager handlerManager;

    public RadioGroup() {
        super();
    }

    public String getGroupName() {
        return groupName;
    }

    public HasValue<Boolean> get(int aIndex) {
        return grouped.get(aIndex);
    }

    public void add(HasValue<Boolean> aItem) {
        if (!grouped.contains(aItem)) {
            if (aItem instanceof HasName) {
                ((HasName) aItem).setName(groupName);
            }
            groupedHandlers.put(aItem, aItem.addValueChangeHandler(this));
            grouped.add(aItem);
        }
    }

    public boolean remove(HasValue<Boolean> aItem) {
        HandlerRegistration handler = groupedHandlers.get(aItem);
        if (handler != null) {
            handler.removeHandler();
        }
        if (aItem instanceof HasName) {
            ((HasName) aItem).setName("");
        }
        return grouped.remove(aItem);
    }

    public void clear() {
        for (HandlerRegistration handler : groupedHandlers.values()) {
            if (handler != null) {
                handler.removeHandler();
            }
        }
        groupedHandlers.clear();
        for (HasValue<Boolean> item : grouped) {
            if (item instanceof HasName) {
                ((HasName) item).setName("");
            }
        }
        grouped.clear();
    }

    public int size() {
        return grouped.size();
    }

    @Override
    public void onValueChange(ValueChangeEvent<Boolean> event) {
        if (Boolean.TRUE.equals(event.getValue())) {
            for (HasValue<Boolean> hv : grouped) {
                if (hv != event.getSource()) {
                    hv.setValue(Boolean.FALSE, false);
                }
            }
        }
    }

    /**
     * Adds this handler to the widget.
     * 
     * @param <H>
     *            the type of handler to add
     * @param type
     *            the event type
     * @param handler
     *            the handler
     * @return {@link HandlerRegistration} used to remove the handler
     */
    public final <H extends EventHandler> HandlerRegistration addHandler(final H handler, GwtEvent.Type<H> type) {
        return ensureHandlers().addHandler(type, handler);
    }

    /**
     * Ensures the existence of the handler manager.
     * 
     * @return the handler manager
     * */
    HandlerManager ensureHandlers() {
        return handlerManager == null ? handlerManager = createHandlerManager() : handlerManager;
    }

    HandlerManager getHandlerManager() {
        return handlerManager;
    }

    public void fireEvent(GwtEvent<?> event) {
        ensureHandlers().fireEvent(event);
    }

    /**
     * Creates the {@link HandlerManager} used by this Widget. You can override
     * this method to create a custom {@link HandlerManager}.
     * 
     * @return the {@link HandlerManager} you want to use
     */
    protected HandlerManager createHandlerManager() {
        return new HandlerManager(this);
    }

}