org.freemedsoftware.gwt.client.widget.AsyncPicklistWidgetBase.java Source code

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Here is the source code for org.freemedsoftware.gwt.client.widget.AsyncPicklistWidgetBase.java

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/*
 * $Id$
 *
 * Authors:
 *      Jeff Buchbinder <jeff@freemedsoftware.org>
 *
 * FreeMED Electronic Medical Record and Practice Management System
 * Copyright (C) 1999-2012 FreeMED Software Foundation
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

package org.freemedsoftware.gwt.client.widget;

import java.util.HashMap;
import java.util.Iterator;
import java.util.List;

import org.freemedsoftware.gwt.client.JsonUtil;
import org.freemedsoftware.gwt.client.WidgetInterface;

import com.google.gwt.event.dom.client.KeyCodes;
import com.google.gwt.event.dom.client.KeyUpEvent;
import com.google.gwt.event.dom.client.KeyUpHandler;
import com.google.gwt.event.logical.shared.HasValueChangeHandlers;
import com.google.gwt.event.logical.shared.SelectionEvent;
import com.google.gwt.event.logical.shared.SelectionHandler;
import com.google.gwt.event.logical.shared.ValueChangeEvent;
import com.google.gwt.event.logical.shared.ValueChangeHandler;
import com.google.gwt.event.shared.HandlerRegistration;
import com.google.gwt.user.client.ui.SuggestBox;
import com.google.gwt.user.client.ui.SuggestOracle;
import com.google.gwt.user.client.ui.SuggestOracle.Callback;
import com.google.gwt.user.client.ui.SuggestOracle.Request;
import com.google.gwt.user.client.ui.SuggestOracle.Suggestion;
import com.google.gwt.user.client.ui.TextBox;
import com.google.gwt.user.client.ui.VerticalPanel;

abstract public class AsyncPicklistWidgetBase extends WidgetInterface implements HasValueChangeHandlers<Integer> {

    protected Integer value = new Integer(0);

    protected HashMap<String, String> map;

    // private final FlexTable listPanel;

    protected SuggestBox searchBox;

    protected TextBox textBox;

    private final VerticalPanel layout;

    private HashMap<ValueChangeHandler<Integer>, HandlerRegistration> changeHandlers = new HashMap<ValueChangeHandler<Integer>, HandlerRegistration>();

    public AsyncPicklistWidgetBase() {
        // Log.setUncaughtExceptionHandler();

        map = new HashMap<String, String>();

        layout = new VerticalPanel();

        textBox = new TextBox();

        searchBox = new SuggestBox(new SuggestOracle() {
            public void requestSuggestions(Request r, Callback cb) {
                loadSuggestions(r.getQuery(), r, cb);
            }
        }, textBox);
        searchBox.addValueChangeHandler(new ValueChangeHandler<String>() {
            @Override
            public void onValueChange(ValueChangeEvent<String> event) {
                // Window.alert("Here be the new value:" + event.getValue());
            }
        });
        searchBox.addKeyUpHandler(new KeyUpHandler() {
            @Override
            public void onKeyUp(KeyUpEvent event) {
                int keyCode = event.getNativeKeyCode();
                switch (keyCode) {
                case KeyCodes.KEY_ESCAPE:
                case KeyCodes.KEY_BACKSPACE:
                    // Clear any current values
                    searchBox.setText("");
                    searchBox.setTitle("");
                    setValue(0);
                    textBox.cancelKey();
                    break;

                default:
                    // Ignore any other keystroke
                    break;
                }
            }
        });
        searchBox.addSelectionHandler(new SelectionHandler<Suggestion>() {
            @Override
            public void onSelection(SelectionEvent<Suggestion> event) {
                Suggestion s = (Suggestion) event.getSelectedItem();
                value = getValueFromText(s.getDisplayString());
                setTitle(s.getDisplayString());
                onSelected();
            }
        });
        searchBox.setLimit(10);
        searchBox.setAnimationEnabled(true);
        layout.add(searchBox);

        initWidget(layout);
    }

    public TextBox getTextEntryWidget() {
        return textBox;
    }

    /**
     * Defined in subclasses to actually return data.
     * 
     * @param req
     * @param r
     * @param cb
     */
    abstract protected void loadSuggestions(String req, final Request r, final Callback cb);

    public AsyncPicklistWidgetBase getWidgetBase() {
        return this;
    }

    /**
     * Resolve value of widget from full text.
     * 
     * @param text
     * @return
     */
    public Integer getValueFromText(String text) {
        String found = new String("");
        Iterator<String> keys = map.keySet().iterator();
        while (found.length() == 0 && keys.hasNext()) {
            String cur = (String) keys.next();
            if (cur.compareTo(text) == 0) {
                found = (String) map.get(cur);
            }
        }
        return new Integer((String) found);
    }

    /**
     * Get string value of currently selected patient.
     * 
     * @return
     */
    public String getText() {
        return searchBox.getText();
    }

    /**
     * Get integer value of currently selected patient.
     * 
     * @return Current selected patient value
     */
    public Integer getValue() {
        return value;
    }

    /**
     * Passthrough for focus.
     * 
     * @param focused
     */
    public void setFocus(boolean focused) {
        searchBox.setFocus(focused);
    }

    /**
     * Set widget value.
     * 
     * @param v
     */
    public void setValue(Integer v) {
        value = v;
    }

    public abstract void getTextForValue(Integer val);

    public void addChangeHandler(ValueChangeHandler<Integer> handler) {
        this.addValueChangeHandler(handler);
    }

    public void removeChangeHandler(ValueChangeHandler<Integer> handler) {
        try {
            changeHandlers.get(handler).removeHandler();
        } catch (Exception ex) {
            JsonUtil.debug(ex.toString());
        }
    }

    @Override
    public HandlerRegistration addValueChangeHandler(ValueChangeHandler<Integer> handler) {
        HandlerRegistration r = addHandler(handler, ValueChangeEvent.getType());
        changeHandlers.put(handler, r);
        return r;
    }

    /**
     * Fire ValueChangeHandler classes attached to this object if there are any.
     * 
     */
    protected void onSelected() {
        // Fire change
        ValueChangeEvent.fire(this, value);
    }

    /**
     * Clear contents of composite widget.
     * 
     */
    public void clear() {

        searchBox.setText("");
        map.clear();
        setValue(0);
    }

    /**
     * Map key and value pair into the widget. Only used by subclasses.
     * 
     * @param key
     * @param value
     */
    protected void addKeyValuePair(List<SuggestOracle.Suggestion> items, final String key, final String value) {
        // Log.debug("Adding key = " + key + ", value = " + value);
        map.put(key, value);
        items.add(new SuggestOracle.Suggestion() {
            public String getDisplayString() {
                return key;
            }

            public String getReplacementString() {
                return key;
            }

            @SuppressWarnings("unused")
            public String getValue() {
                return value;
            }
        });
    }

    @Override
    public void setWidth(String width) {
        // TODO Auto-generated method stub
        super.setWidth(width);
        searchBox.setWidth(width);
    }
}