datefield.java

j2me下的1套UI框架.包含j2me开发中会应用的各种低级组件

package com.jmobilecore.ui;

import com.jmobilecore.ui.core.TextField;
import com.jmobilecore.ui.core.TextComponent;

import java.util.Date;
import java.util.Calendar;

/**
 * This class displays formatted textfield for entering date information
 * Format of the date is specified by user.
 * Blocks of digits are separated by divider.
 *
 * @author Igor Shevlyakov - initial implementation
 * @author Greg Gridin - redesign
 */
public class DateField extends TextField {

// internal constants and variables
    static final protected int days[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
    protected int day, month, year;

    /**
     * Date format, example: 2004:03:26.
     */
    public static final byte YYYY_MM_DD = 1;

    /**
     * Date format, example: 26/03/2004.
     */
    public static final byte DD_MM_YYYY = 2;

    /**
     * Date format, example: 03/26/2004.
     */
    public static final byte MM_DD_YYYY = 3;

    /**
     * The current DateField formatting style.
     */
    protected byte STYLE;

    /**
     * The divider for date formatting
     */
    public char divider = '/';

    /**
     * Constructs a new <code>DateField</code> field.
     */
    public DateField() {
        this(MM_DD_YYYY, '/', null);
    }

    /**
     * Constructs a new <code>DateField</code> object of specified format.
     *
     * @param style   the date format
     */
    public DateField(byte style) {
        this(style, '/', null);
    }

    /**
     * Constructs a new <code>DateField</code> object of specified format.
     *
     * @param style   the date format
     * @param divider the divider for the date field
     */
    public DateField(byte style, char divider) {
        this(style, divider, null);
    }

    /**
     * Constructs a new <code>DateField</code> object of specified format
     * with the specified value.
     *
     * @param style   the date format
     * @param divider the divider for the date field
     * @param date    the date value
     * @see #setStyle
     */
    public DateField(byte style, char divider, Date date) {
        super(-1, TextComponent.C_NUMERIC);
        setStyle(style, divider, date);
    }

    /**
     * Initialize date field composer
     *
     * @return <code>CustomFieldComposer</code> for date field
     */
    protected CustomFieldComposer initComposer() {

        DigitalBlockComposer[] textBlocks = new DigitalBlockComposer[3];
        textBlocks[0] = new DigitalBlockComposer(DigitalBlockComposer.FIXED_SIZE, 4, ' ', 1970, 2038);
        textBlocks[1] = new DigitalBlockComposer(DigitalBlockComposer.FIXED_SIZE, 2, ' ', 1, 12);
        textBlocks[2] = new DigitalBlockComposer(DigitalBlockComposer.FIXED_SIZE, 2, ' ', 1, 31);
        return new CustomFieldComposer(textBlocks) {
            public void setText(String text) {
            }

            public boolean caretLeft() {
                if (textBlocks[curBlock].caretLeft()) {
                    if (textBlocks[curBlock].getCaretPosition() >= 0) {
                        return true;
                    }
                }
                boolean isComplete = textBlocks[curBlock].isComplete();
                if (!isComplete) return true;
                return setCaretPosition(getCaretPosition()-1);
            }

            public boolean caretRight() {
                if (textBlocks[curBlock].caretRight()) {
                    if (textBlocks[curBlock].getCaretPosition() < textBlocks[curBlock].getMaxSize()) {
                        return true;
                    }
                }
                boolean isComplete = textBlocks[curBlock].isComplete();
                if (!isComplete) return true;
                return setCaretPosition(getCaretPosition());
            }

            public int getCaretPosition() {
                if (STYLE==YYYY_MM_DD) {
                    if (curBlock==0) return textBlocks[0].getCaretPosition();
                    if (curBlock==1) return textBlocks[1].getCaretPosition()+4;
                    if (curBlock==2) return textBlocks[2].getCaretPosition()+6;
                }
                if (STYLE==DD_MM_YYYY) {
                    if (curBlock==0) return textBlocks[0].getCaretPosition()+4;
                    if (curBlock==1) return textBlocks[1].getCaretPosition()+2;
                    if (curBlock==2) return textBlocks[2].getCaretPosition();
                }
                if (STYLE==MM_DD_YYYY) {
                    if (curBlock==0) return textBlocks[0].getCaretPosition()+4;
                    if (curBlock==1) return textBlocks[1].getCaretPosition();
                    if (curBlock==2) return textBlocks[2].getCaretPosition()+2;
                }
                return 0;
            }

            public boolean setCaretPosition(int caretPosition) {

                if (caretPosition<0 || caretPosition>8) {
                    return false;
                }
                if (STYLE==YYYY_MM_DD) {
                    if (caretPosition<4) { textBlocks[curBlock=0].setCaretPosition(caretPosition); }
                    else if (caretPosition<6) { textBlocks[curBlock=1].setCaretPosition(caretPosition-4); }
                    else textBlocks[curBlock=2].setCaretPosition(caretPosition-6);
                    return true;
                }
                if (STYLE==DD_MM_YYYY) {
                    if (caretPosition<2) textBlocks[curBlock=2].setCaretPosition(caretPosition);
                    else if (caretPosition<4) textBlocks[curBlock=1].setCaretPosition(caretPosition-2);
                    else textBlocks[curBlock=0].setCaretPosition(caretPosition-4);
                    return true;
                }
                if (STYLE==MM_DD_YYYY) {
                    if (caretPosition<2) textBlocks[curBlock=1].setCaretPosition(caretPosition);
                    else if (caretPosition<4) textBlocks[curBlock=2].setCaretPosition(caretPosition-2);
                    else textBlocks[curBlock=0].setCaretPosition(caretPosition-4);
                    return true;
                }
                return false;
            }
        };
    }

    /**
     * Sets <code>day, month, year</code> variables
     * If the field contains invalid value, the method sets
     * variable <code>year</code> to <code>-1</code>
     */
    protected void getBlocks() {
        day = month = year = 0;

        try {
            DigitalBlockComposer blocks[] = (DigitalBlockComposer[])((CustomFieldComposer) composer).textBlocks;
            year = (int) blocks[0].getValue();
            month = (int) blocks[1].getValue();
            day = (int) blocks[2].getValue();
        } catch (Exception e) {
            year = -1;
            return;
        }
    }

    protected char[] getFormattedText(boolean calcCursorOffset) {

        TextBlockComposer blocks[] = ((CustomFieldComposer) composer).textBlocks;
        currentLength = 10;
        char formattedText[] = new char[currentLength];
        int curBlock = ((CustomFieldComposer)composer).getCurrentBlock();
        int fmtCaretPos = 0;
        char [] yearText = blocks[0].getChars();
        char [] monthText = blocks[1].getChars();
        char [] dayText = blocks[2].getChars();
        int yearPos = blocks[0].getCaretPosition();
        int monthPos = blocks[1].getCaretPosition();
        int dayPos = blocks[2].getCaretPosition();

        if (STYLE==YYYY_MM_DD) {
            System.arraycopy(yearText, 0, formattedText, 0, 4);
            formattedText[4] = divider;
            System.arraycopy(monthText, 0, formattedText, 5, 2);
            formattedText[7] = divider;
            System.arraycopy(dayText, 0, formattedText, 8, 2);
            if (curBlock == 0) {
                fmtCaretPos = yearPos;
            }
            if (curBlock == 1) {
                fmtCaretPos = 5 + monthPos;
            }
            if (curBlock == 2) {
                fmtCaretPos = 8 + dayPos;
            }
        }
        if (STYLE==DD_MM_YYYY) {
            System.arraycopy(dayText, 0, formattedText, 0, 2);
            formattedText[2] = divider;
            System.arraycopy(monthText, 0, formattedText, 3, 2);
            formattedText[5] = divider;
            System.arraycopy(yearText, 0, formattedText, 6, 4);
            if (curBlock == 0) {
                fmtCaretPos = 6 + yearPos;
            }
            if (curBlock == 1) {
                fmtCaretPos = 3 + monthPos;
            }
            if (curBlock == 2) {
                fmtCaretPos = dayPos;
            }
        }
        if (STYLE==MM_DD_YYYY) {
            System.arraycopy(monthText, 0, formattedText, 0, 2);
            formattedText[2] = divider;
            System.arraycopy(dayText, 0, formattedText, 3, 2);
            formattedText[5] = divider;
            System.arraycopy(yearText, 0, formattedText, 6, 4);
            if (curBlock == 0) {
                fmtCaretPos = 6 + yearPos;
            }
            if (curBlock == 1) {
                fmtCaretPos = monthPos;
            }
            if (curBlock == 2) {
                fmtCaretPos = 3 + dayPos;
            }
        }

        if (calcCursorOffset) {
            calculatedCaretPosition = fmtCaretPos;
            calculatedCursorOffset = getCursorOffset(formattedText, calculatedCaretPosition);
        }
        return formattedText;
    }

    /**
     * Get formatted representation of <code>Ipv4Field</code> value
     * or <code>null</code> if <code>IPv4Field</code> object value is set to null or incomplete
     *
     * @return the <code>String</code> representing bank card number
     */
    public String getFormattedText() {
        if (isValid()) {
            return String.valueOf(getFormattedText(false));
        }
        return null;
    }

    public void setStyle(byte newStyle) {
        setStyle(newStyle, '/', null);
    }

    public void setStyle(byte newStyle, char divider) {

        setStyle(newStyle, divider, null);
    }

    public void setStyle(byte newStyle, char divider, Date newDate) {

        if (newStyle < 1 || newStyle > 3) return;
        Date date = newDate;
        if (date==null) date = getDate();
        STYLE = newStyle;
        this.divider = divider;
        if (composer != null) {
            composer.destructor();
        }
        composer = initComposer();
        setDate(date);
    }

    public byte getStyle() {

        return STYLE;
    }

    /**
     * Returns the date value that is presented by this component.
     * Time portion of returned <code>Date</code> value is set to 0 (hours,
     * minutes, seconds)
     *
     * @return the <code>Date</code> representing the specified date
     */
    public Date getDate() {
        if (!isValid()) {
            return null;
        }
        Calendar cal = Calendar.getInstance();
        cal.set(Calendar.DATE, day);
        cal.set(Calendar.MONTH, month - 1);
        cal.set(Calendar.YEAR, year);
        cal.set(Calendar.HOUR_OF_DAY, 0);
        cal.set(Calendar.MINUTE, 0);
        cal.set(Calendar.SECOND, 0);
        cal.set(Calendar.MILLISECOND, 0);
        return cal.getTime();
    }

    /**
     * Sets date that is presented by this date component to be the
     * specified value.
     * Time portion of <code>date</code> argument is ignored
     *
     * @param date the date value
     */
    public void setDate(Date date) {

        if (date == null) {
            ((CustomFieldComposer) composer).clear();
        } else {
            Calendar cal = Calendar.getInstance();
            cal.setTime(date);
            day = cal.get(Calendar.DATE);
            month = cal.get(Calendar.MONTH) + 1;
            year = cal.get(Calendar.YEAR);
            cal = null;

            String dayStr = ((day < 10) ? "0" : "") + String.valueOf(day);
            String monthStr = ((month < 10) ? "0" : "") + String.valueOf(month);
            String yearStr = String.valueOf(year);
            DigitalBlockComposer blocks[] = (DigitalBlockComposer[])((CustomFieldComposer) composer).textBlocks;
            blocks[0].setText(yearStr);
            blocks[1].setText(monthStr);
            blocks[2].setText(dayStr);
        }
        setCaretPosition(0);
    }

    /**
     * This method should not be used for the class and intentionally set to deprecated
     * Use #getFormattedText() method instead.
     *
     * @deprecated
     */
    public String getText() {
        return null;
    }

    /**
     * This method should not be used for the class and intentionally set to
     * deprecated
     * Use #setDate(Date date) method instead.
     *
     * @deprecated
     */
    public void setText(String text) {
    }

    /**
     * Tests date field value for correctness
     *
     * @return <code>true</code> if the date field is valid
     *         <code>false</code> otherwise
     */
    public boolean isValid() {
        if (!((CustomFieldComposer) composer).isComplete()) return false;
        getBlocks();
        if (year <= 0) return false;
        days[1] = ((year % 4) == 0) ? 29 : 28;
        return day <= days[month - 1];
    }

}