PC World Komputer 1995 November/PCWK1195.iso/inne/win95/sieciowe/hotja32.lzh/hotjava/classsrc/browser/forms/select.java

Text File | 1995-08-11 | 5KB | 213 lines

/*
 * @(#)select.java    1.7 95/03/14 Jonathan Payne
 *
 * Copyright (c) 1994 Sun Microsystems, Inc. All Rights Reserved.
 *
 * Permission to use, copy, modify, and distribute this software
 * and its documentation for NON-COMMERCIAL purposes and without
 * fee is hereby granted provided that this copyright notice
 * appears in all copies. Please refer to the file "copyright.html"
 * for further important copyright and licensing information.
 *
 * SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF
 * THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
 * TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
 * PARTICULAR PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR
 * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
 * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
 */

package browser.forms;

import browser.FormTagRef;
import awt.DisplayItem;
import awt.Component;
import awt.DisplayItemWindow;
import awt.NativeDisplayItem;
import awt.OptionMenu;
import awt.List;
import browser.WRFormatter;
import java.util.Hashtable;

/**
 * An instance of class option is created for each occurrence of a
 * <select size=1> in a form.
 *
 * @version 1.3, 12 Dec 1994
 * @author Jonathan Payne
 */

public class select extends FormItem {
    boolean useOptionMenu;
    boolean selected;
    boolean finished = false;
    Hashtable    optionValues;

    public DisplayItem buildDisplayItem(WRFormatter f) {
    NativeDisplayItem   ndi = new FormDisplayItem();
    String            sizeAttribute;
    int            size = 1;
    boolean            multiple;

    size = getIntegerAttribute("size", 1);
    multiple = owner.getAttribute("multiple") != null;

    useOptionMenu = !(multiple || size >= 2);

    Component c;

    if (useOptionMenu) {
        c = new OptionMenu(f.win, "", null);
    } else {
        c = new List(f.win, null, null, size, multiple);
    }
    ndi.setComponent(c);
    ndi.reshape(ndi.x, ndi.y, c.width, c.height);

    if (optionValues != null) {
        optionValues = null;
    }

    return ndi;
    }

    public void addOption(String option, String value, boolean selected) {
    /* This item has already been built once, and now we're building
       it again because we're relayingout the document.  But we want
       to preserve the current settings.  This feels slightly bogus. */
    if (finished) {
        return;
    }

    int limit = option.length();
    int i0 = 0;
    int c;

    while (i0 < limit) {
        if (!((c = option.charAt(i0)) == ' ' || c == '\t' || c == '\n'))
        break;
        i0 += 1;
    }
    int i1 = limit;
    while (i1 > i0) {
        if (!((c = option.charAt(i1 - 1)) == ' ' || c == '\t' || c == '\n'))
        break;
        i1 -= 1;
    }
    option = option.substring(i0, i1);

    /* If a value was associated with this option, store that
       now.  It's used instead of the name of the option, when
       the value of this select is requested. */
    if (value != null) {
        if (optionValues == null) {
        optionValues = new Hashtable();
        }
        optionValues.put(option, value);
    }

    int count;

    if (useOptionMenu) {
        OptionMenu  om = (OptionMenu) getComponent();

        om.addItem(option);
        count = om.nItems();
    } else {
        List    list = (List) getComponent();

        list.addItem(option);
        count = list.nItems();
    }
    if (selected) {
        select(count - 1);
    }
    }

    public void finish() {
    if (!finished) {
        if (!selected) {
        select(0);
        }
        finished = true;
    }
    }

    void select(int item) {
    if (useOptionMenu) {
        OptionMenu  om = (OptionMenu) getComponent();

        om.select(item);
    } else {
        List    list = (List) getComponent();

        list.select(item);
    }
    selected = true;
    }

    public void acceptStringValue(String newValue) {}

    public void reset() {
    }

    /* If a value=foo was specified, return the value; otherwise,
       return the actual item displayed in the list/option menu. */
    private String optionSpecifiedValue(String option) {
    if (optionValues != null) {
        String  value = (String) optionValues.get(option);

        if (value != null) {
        return value;
        }
    }
    return option;
    }

    final String getOptionMenuValue() {
    OptionMenu  om = (OptionMenu) getComponent();

    return optionSpecifiedValue(om.selectedItem());
    }

    private int    offset;

    final String getListValue() {
    List    list = (List) getComponent();

    int    cnt = list.nItems() - offset;

    while (--cnt >= 0) {
        if (list.isSelected(offset++)) {
        return optionSpecifiedValue(list.itemAt(offset - 1));
        }
    }
    return null;
    }

    public String getFormString() {
    if (useOptionMenu) {
        return name + "=" + processString(getOptionMenuValue());
    } else {
        String  value;
        String  result = "";
        boolean doneOne = false;

        offset = 0;

        while ((value = getListValue()) != null) {
        if (doneOne) {
            result += "&";
        }
        result += name + "=" + processString(value);
        doneOne = true;
        }
        return result;
    }
    }

    public String getFormValue() {
    throw new Exception("Internal error: select form item");
    }
}