PreferencesActivity.java

/*
 * Copyright (C) 2008 ZXing authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.zxing.client.android;

import android.content.SharedPreferences;
import android.content.SharedPreferences.OnSharedPreferenceChangeListener;
import android.os.Bundle;
import android.preference.CheckBoxPreference;
import android.preference.PreferenceActivity;
import android.preference.PreferenceScreen;
import com.google.zxing.FakeR;

import java.util.ArrayList;
import java.util.Collection;

/**
 * The main settings activity.
 *
 * @author dswitkin@google.com (Daniel Switkin)
 */
public final class PreferencesActivity extends PreferenceActivity
    implements OnSharedPreferenceChangeListener {

  public static final String KEY_DECODE_1D = "preferences_decode_1D";
  public static final String KEY_DECODE_QR = "preferences_decode_QR";
  public static final String KEY_DECODE_DATA_MATRIX = "preferences_decode_Data_Matrix";
  public static final String KEY_CUSTOM_PRODUCT_SEARCH = "preferences_custom_product_search";

  public static final String KEY_PLAY_BEEP = "preferences_play_beep";
  public static final String KEY_VIBRATE = "preferences_vibrate";
  public static final String KEY_COPY_TO_CLIPBOARD = "preferences_copy_to_clipboard";
  public static final String KEY_FRONT_LIGHT = "preferences_front_light";
  public static final String KEY_BULK_MODE = "preferences_bulk_mode";
  public static final String KEY_REMEMBER_DUPLICATES = "preferences_remember_duplicates";
  public static final String KEY_SUPPLEMENTAL = "preferences_supplemental";
  public static final String KEY_AUTO_FOCUS = "preferences_auto_focus";
  public static final String KEY_SEARCH_COUNTRY = "preferences_search_country";

  public static final String KEY_DISABLE_CONTINUOUS_FOCUS = "preferences_disable_continuous_focus";
  //public static final String KEY_DISABLE_EXPOSURE = "preferences_disable_exposure";

  public static final String KEY_HELP_VERSION_SHOWN = "preferences_help_version_shown";

  private CheckBoxPreference decode1D;
  private CheckBoxPreference decodeQR;
  private CheckBoxPreference decodeDataMatrix;

  private static FakeR fakeR;

  @Override
  protected void onCreate(Bundle icicle) {
    super.onCreate(icicle);
	fakeR = new FakeR(this);
    addPreferencesFromResource(fakeR.getId("xml", "preferences"));

    PreferenceScreen preferences = getPreferenceScreen();
    preferences.getSharedPreferences().registerOnSharedPreferenceChangeListener(this);
    decode1D = (CheckBoxPreference) preferences.findPreference(KEY_DECODE_1D);
    decodeQR = (CheckBoxPreference) preferences.findPreference(KEY_DECODE_QR);
    decodeDataMatrix = (CheckBoxPreference) preferences.findPreference(KEY_DECODE_DATA_MATRIX);
    disableLastCheckedPref();
  }

  @Override
  public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
    disableLastCheckedPref();
  }

  private void disableLastCheckedPref() {
    Collection<CheckBoxPreference> checked = new ArrayList<CheckBoxPreference>(3);
    if (decode1D.isChecked()) {
      checked.add(decode1D);
    }
    if (decodeQR.isChecked()) {
      checked.add(decodeQR);
    }
    if (decodeDataMatrix.isChecked()) {
      checked.add(decodeDataMatrix);
    }
    boolean disable = checked.size() < 2;
    CheckBoxPreference[] checkBoxPreferences = {decode1D, decodeQR, decodeDataMatrix};
    for (CheckBoxPreference pref : checkBoxPreferences) {
      pref.setEnabled(!(disable && checked.contains(pref)));
    }
  }

}