Android Preference for Selecting Hour of Day (12/24 Hour Clock Compatible)

HourOfDayPreference.java

/*
The MIT License (MIT)

Copyright (c) 2015 Brandon Sara (http://bsara.github.io)

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/


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



public class HourOfDayPreference extends DialogPreference {

  private String[] _hourStrings;
  private String[] _ampmStrings;

  private NumberPicker _hourView;
  private NumberPicker _ampmView;

  private boolean _isValueSet;
  private int     _value;



  // region Constructors


  public HourOfDayPreference(Context context, AttributeSet attrs) {
    super(context, attrs);
    this.init();
  }


  public HourOfDayPreference(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    this.init();
  }


  private void init() {
    _hourStrings = this.getContext().getResources().getStringArray(DateFormat.is24HourFormat(this.getContext()) ? R.array.customPref_hourOfDay_hours_24 : R.array.customPref_hourOfDay_hours_12);
    _ampmStrings = this.getContext().getResources().getStringArray(R.array.customPref_hourOfDay_ampm);

    _hourView = null;
    _ampmView = null;

    _isValueSet = false;
    _value = 0;

    this.setDialogLayoutResource(R.layout.pref_hourofday);
  }


  // endregion



  // region Event Handlers


  @Override
  protected void onBindDialogView(View view) {
    super.onBindDialogView(view);

    final boolean isUsing24HourFormat = DateFormat.is24HourFormat(this.getContext());

    _hourView = (NumberPicker)view.findViewById(R.id.customPref_hourOfDay_hour);
    _hourView.setSaveFromParentEnabled(false);
    _hourView.setSaveEnabled(true);
    _hourView.setMinValue(0);
    _hourView.setMaxValue(isUsing24HourFormat ? 23 : 11);
    _hourView.setDisplayedValues(_hourStrings);

    _ampmView = (NumberPicker)view.findViewById(R.id.customPref_hourOfDay_ampm);
    _ampmView.setSaveFromParentEnabled(false);
    _ampmView.setSaveEnabled(true);
    if (isUsing24HourFormat) {
      _ampmView.setVisibility(View.GONE);
    } else {
      _ampmView.setVisibility(View.VISIBLE);
      _ampmView.setMinValue(0);
      _ampmView.setMaxValue(1);
      _ampmView.setDisplayedValues(_ampmStrings);

      if (_value > 11) {
        _hourView.setValue(_value - 12);
        _ampmView.setValue(1);
        return;
      }
      _ampmView.setValue(0);
    }
    _hourView.setValue(_value);
  }


  @Override
  protected void onSetInitialValue(boolean restorePersistedValue, Object defaultValue) {
    if (defaultValue == null || !(defaultValue instanceof Integer)) {
      defaultValue = 0;
    }

    if (restorePersistedValue) {
      _value = this.getPersistedInt((Integer)defaultValue);
      _isValueSet = true;
      return;
    }
    this.setValue((Integer)defaultValue);
  }


  @Override
  protected void onDialogClosed(boolean positiveResult) {
    super.onDialogClosed(positiveResult);

    if (positiveResult) {
      int hour = _hourView.getValue();

      if (!DateFormat.is24HourFormat(this.getContext()) && _ampmView.getValue() == 1) {
        hour += 12;
      }

      if (this.callChangeListener(hour)) {
        this.setValue(hour);
      }
    }
  }


  // endregion



  // region Getters/Setters


  public int getValue() {
    return _value;
  }


  public void setValue(int newValue) {
    final boolean wasChanged = (newValue != _value);

    if (wasChanged || !_isValueSet) {
      _value = newValue;
      _isValueSet = true;

      this.persistInt(_value);

      if (wasChanged) {
        this.notifyChanged();
      }
    }
  }


  @Override
  public CharSequence getSummary() {
    if (DateFormat.is24HourFormat(this.getContext())) {
      return _hourStrings[ _value ];
    }
    if (_value > 11) {
      return String.format("%s %s", _hourStrings[ _value - 12 ], _ampmStrings[ 1 ]);
    }
    return String.format("%s %s", _hourStrings[ _value ], _ampmStrings[ 0 ]);
  }


  // endregion
}

layout_pref_hourofday.xml

<!--
The MIT License (MIT)

Copyright (c) 2015 Brandon Sara (http://bsara.github.io)

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
-->

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:orientation="horizontal"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:gravity="center">
  <NumberPicker
    android:id="@+id/customPref_hourOfDay_hour"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_margin="2dp" />
  <NumberPicker
    android:id="@+id/customPref_hourOfDay_ampm"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_margin="2dp" />
</LinearLayout>

strings_pref_hourofday.xml

<!--
The MIT License (MIT)

Copyright (c) 2015 Brandon Sara (http://bsara.github.io)

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
-->

<?xml version="1.0" encoding="utf-8"?>
<resources>
  <string-array name="customPref_hourOfDay_hours_12">
    <item>12:00</item>
    <item>1:00</item>
    <item>2:00</item>
    <item>3:00</item>
    <item>4:00</item>
    <item>5:00</item>
    <item>6:00</item>
    <item>7:00</item>
    <item>8:00</item>
    <item>9:00</item>
    <item>10:00</item>
    <item>11:00</item>
  </string-array>
  <string-array name="customPref_hourOfDay_hours_24">
    <item>00:00</item>
    <item>01:00</item>
    <item>02:00</item>
    <item>03:00</item>
    <item>04:00</item>
    <item>05:00</item>
    <item>06:00</item>
    <item>07:00</item>
    <item>08:00</item>
    <item>09:00</item>
    <item>10:00</item>
    <item>11:00</item>
    <item>12:00</item>
    <item>13:00</item>
    <item>14:00</item>
    <item>15:00</item>
    <item>16:00</item>
    <item>17:00</item>
    <item>18:00</item>
    <item>19:00</item>
    <item>20:00</item>
    <item>21:00</item>
    <item>22:00</item>
    <item>23:00</item>
  </string-array>
  <string-array name="customPref_hourOfDay_ampm">
    <item>AM</item>
    <item>PM</item>
  </string-array>
</resources>