1 /* 2 * Copyright 2018 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package androidx.preference; 18 19 import android.content.DialogInterface; 20 import android.os.Bundle; 21 22 import androidx.annotation.NonNull; 23 import androidx.appcompat.app.AlertDialog; 24 25 public class ListPreferenceDialogFragmentCompat extends PreferenceDialogFragmentCompat { 26 27 private static final String SAVE_STATE_INDEX = "ListPreferenceDialogFragment.index"; 28 private static final String SAVE_STATE_ENTRIES = "ListPreferenceDialogFragment.entries"; 29 private static final String SAVE_STATE_ENTRY_VALUES = 30 "ListPreferenceDialogFragment.entryValues"; 31 32 private int mClickedDialogEntryIndex; 33 private CharSequence[] mEntries; 34 private CharSequence[] mEntryValues; 35 newInstance(String key)36 public static ListPreferenceDialogFragmentCompat newInstance(String key) { 37 final ListPreferenceDialogFragmentCompat fragment = 38 new ListPreferenceDialogFragmentCompat(); 39 final Bundle b = new Bundle(1); 40 b.putString(ARG_KEY, key); 41 fragment.setArguments(b); 42 return fragment; 43 } 44 45 @Override onCreate(Bundle savedInstanceState)46 public void onCreate(Bundle savedInstanceState) { 47 super.onCreate(savedInstanceState); 48 if (savedInstanceState == null) { 49 final ListPreference preference = getListPreference(); 50 51 if (preference.getEntries() == null || preference.getEntryValues() == null) { 52 throw new IllegalStateException( 53 "ListPreference requires an entries array and an entryValues array."); 54 } 55 56 mClickedDialogEntryIndex = preference.findIndexOfValue(preference.getValue()); 57 mEntries = preference.getEntries(); 58 mEntryValues = preference.getEntryValues(); 59 } else { 60 mClickedDialogEntryIndex = savedInstanceState.getInt(SAVE_STATE_INDEX, 0); 61 mEntries = savedInstanceState.getCharSequenceArray(SAVE_STATE_ENTRIES); 62 mEntryValues = savedInstanceState.getCharSequenceArray(SAVE_STATE_ENTRY_VALUES); 63 } 64 } 65 66 @Override onSaveInstanceState(@onNull Bundle outState)67 public void onSaveInstanceState(@NonNull Bundle outState) { 68 super.onSaveInstanceState(outState); 69 outState.putInt(SAVE_STATE_INDEX, mClickedDialogEntryIndex); 70 outState.putCharSequenceArray(SAVE_STATE_ENTRIES, mEntries); 71 outState.putCharSequenceArray(SAVE_STATE_ENTRY_VALUES, mEntryValues); 72 } 73 getListPreference()74 private ListPreference getListPreference() { 75 return (ListPreference) getPreference(); 76 } 77 78 @Override onPrepareDialogBuilder(AlertDialog.Builder builder)79 protected void onPrepareDialogBuilder(AlertDialog.Builder builder) { 80 super.onPrepareDialogBuilder(builder); 81 82 builder.setSingleChoiceItems(mEntries, mClickedDialogEntryIndex, 83 new DialogInterface.OnClickListener() { 84 @Override 85 public void onClick(DialogInterface dialog, int which) { 86 mClickedDialogEntryIndex = which; 87 88 /* 89 * Clicking on an item simulates the positive button 90 * click, and dismisses the dialog. 91 */ 92 ListPreferenceDialogFragmentCompat.this.onClick(dialog, 93 DialogInterface.BUTTON_POSITIVE); 94 dialog.dismiss(); 95 } 96 }); 97 98 /* 99 * The typical interaction for list-based dialogs is to have 100 * click-on-an-item dismiss the dialog instead of the user having to 101 * press 'Ok'. 102 */ 103 builder.setPositiveButton(null, null); 104 } 105 106 @Override onDialogClosed(boolean positiveResult)107 public void onDialogClosed(boolean positiveResult) { 108 final ListPreference preference = getListPreference(); 109 if (positiveResult && mClickedDialogEntryIndex >= 0) { 110 String value = mEntryValues[mClickedDialogEntryIndex].toString(); 111 if (preference.callChangeListener(value)) { 112 preference.setValue(value); 113 } 114 } 115 } 116 117 } 118