TimePickerPreference.java

/* Sourced from http://www.ebessette.com/d/TimePickerPreference
 * on 2010-11-27 by jessev
 */

package com.fsck.k9.preferences;

import android.content.Context;
import android.preference.DialogPreference;
import android.text.format.DateFormat;
import android.util.AttributeSet;
import android.view.View;
import android.widget.TimePicker;

/**
 * A preference type that allows a user to choose a time
 */
public class TimePickerPreference extends DialogPreference implements
    TimePicker.OnTimeChangedListener {

    /**
     * The validation expression for this preference
     */
    public static final String VALIDATION_EXPRESSION = "[0-2]*[0-9]:[0-5]*[0-9]";

    /**
     * The default value for this preference
     */
    private String defaultValue;
    /**
     * Store the original value, in case the user
     * chooses to abort the {@link DialogPreference}
     * after making a change.
     */
    private int originalHour = 0;
    /**
     * Store the original value, in case the user
     * chooses to abort the {@link DialogPreference}
     * after making a change.
     */
    private int originalMinute = 0;
    /**
     * @param context
     * @param attrs
     */
    public TimePickerPreference(final Context context, final AttributeSet attrs) {
        super(context, attrs);
        initialize();
    }

    /**
     * @param context
     * @param attrs
     * @param defStyle
     */
    public TimePickerPreference(final Context context, final AttributeSet attrs,
                                final int defStyle) {
        super(context, attrs, defStyle);
        initialize();
    }

    /**
     * Initialize this preference
     */
    private void initialize() {
        setPersistent(true);
    }

    /*
     * (non-Javadoc)
     *
     * @see android.preference.DialogPreference#onCreateDialogView()
     */
    @Override
    protected View onCreateDialogView() {

        TimePicker tp = new TimePicker(getContext());
        tp.setIs24HourView(DateFormat.is24HourFormat(getContext()));
        tp.setOnTimeChangedListener(this);
        originalHour = getHour();
        originalMinute = getMinute();
        if (originalHour >= 0 && originalMinute >= 0) {
            tp.setCurrentHour(originalHour);
            tp.setCurrentMinute(originalMinute);
        }

        return tp;
    }

    /**
     * @see
     * android.widget.TimePicker.OnTimeChangedListener#onTimeChanged(android
     * .widget.TimePicker, int, int)
     */
    @Override
    public void onTimeChanged(final TimePicker view, final int hour, final int minute) {

        persistString(String.format("%02d:%02d", hour, minute));
        callChangeListener(String.format("%02d:%02d", hour, minute));
    }

    /**
     * If not a positive result, restore the original value
     * before going to super.onDialogClosed(positiveResult).
     */
    @Override
    protected void onDialogClosed(boolean positiveResult) {

        if (!positiveResult) {
            persistString(String.format("%02d:%02d", originalHour, originalMinute));
            callChangeListener(String.format("%02d:%02d", originalHour, originalMinute));
        }
        super.onDialogClosed(positiveResult);
    }

    /**
     * @see android.preference.Preference#setDefaultValue(java.lang.Object)
     */
    @Override
    public void setDefaultValue(final Object defaultValue) {
        // BUG this method is never called if you use the 'android:defaultValue' attribute in your XML preference file, not sure why it isn't

        super.setDefaultValue(defaultValue);

        if (!(defaultValue instanceof String)) {
            return;
        }

        if (!((String) defaultValue).matches(VALIDATION_EXPRESSION)) {
            return;
        }

        this.defaultValue = (String) defaultValue;
    }

    /**
     * Get the hour value (in 24 hour time)
     *
     * @return The hour value, will be 0 to 23 (inclusive) or -1 if illegal
     */
    private int getHour() {
        String time = getTime();
        if (time == null || !time.matches(VALIDATION_EXPRESSION)) {
            return -1;
        }

        return Integer.valueOf(time.split(":")[0]);
    }

    /**
     * Get the minute value
     *
     * @return the minute value, will be 0 to 59 (inclusive) or -1 if illegal
     */
    private int getMinute() {
        String time = getTime();
        if (time == null || !time.matches(VALIDATION_EXPRESSION)) {
            return -1;
        }

        return Integer.valueOf(time.split(":")[1]);
    }

    /**
     * Get the time. It is only legal, if it matches
     * {@link #VALIDATION_EXPRESSION}.
     *
     * @return the time as hh:mm
     */
    public String getTime() {
        return getPersistedString(this.defaultValue);
    }

}