• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (C) 2015 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 android.support.v14.preference;
18 
19 import android.content.Context;
20 import android.content.SharedPreferences;
21 import android.content.res.TypedArray;
22 import android.os.Parcel;
23 import android.os.Parcelable;
24 import android.support.annotation.ArrayRes;
25 import android.support.annotation.NonNull;
26 import android.support.v4.content.SharedPreferencesCompat;
27 import android.support.v4.content.res.TypedArrayUtils;
28 import android.support.v7.preference.DialogPreference;
29 import android.util.AttributeSet;
30 
31 import java.util.Collections;
32 import java.util.HashSet;
33 import java.util.Set;
34 
35 /**
36  * A {@link android.support.v7.preference.Preference} that displays a list of entries as
37  * a dialog.
38  * <p>
39  * This preference will store a set of strings into the SharedPreferences.
40  * This set will contain one or more values from the
41  * {@link #setEntryValues(CharSequence[])} array.
42  *
43  * @attr ref android.R.styleable#MultiSelectListPreference_entries
44  * @attr ref android.R.styleable#MultiSelectListPreference_entryValues
45  */
46 public class MultiSelectListPreference extends DialogPreference {
47     private CharSequence[] mEntries;
48     private CharSequence[] mEntryValues;
49     private Set<String> mValues = new HashSet<>();
50 
MultiSelectListPreference( Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes)51     public MultiSelectListPreference(
52             Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
53         super(context, attrs, defStyleAttr, defStyleRes);
54 
55         final TypedArray a = context.obtainStyledAttributes(attrs,
56                 R.styleable.MultiSelectListPreference, defStyleAttr,
57                 defStyleRes);
58 
59         mEntries = TypedArrayUtils.getTextArray(a,
60                 R.styleable.MultiSelectListPreference_entries,
61                 R.styleable.MultiSelectListPreference_android_entries);
62 
63         mEntryValues = TypedArrayUtils.getTextArray(a,
64                 R.styleable.MultiSelectListPreference_entryValues,
65                 R.styleable.MultiSelectListPreference_android_entryValues);
66 
67         a.recycle();
68     }
69 
MultiSelectListPreference(Context context, AttributeSet attrs, int defStyleAttr)70     public MultiSelectListPreference(Context context, AttributeSet attrs, int defStyleAttr) {
71         this(context, attrs, defStyleAttr, 0);
72     }
73 
MultiSelectListPreference(Context context, AttributeSet attrs)74     public MultiSelectListPreference(Context context, AttributeSet attrs) {
75         this(context, attrs, R.attr.dialogPreferenceStyle);
76     }
77 
MultiSelectListPreference(Context context)78     public MultiSelectListPreference(Context context) {
79         this(context, null);
80     }
81 
82     /**
83      * Attempts to persist a set of Strings to the {@link android.content.SharedPreferences}.
84      * <p>
85      * This will check if this Preference is persistent, get an editor from
86      * the {@link android.preference.PreferenceManager}, put in the strings, and check if we should
87      * commit (and commit if so).
88      *
89      * @param values The values to persist.
90      * @return True if the Preference is persistent. (This is not whether the
91      *         value was persisted, since we may not necessarily commit if there
92      *         will be a batch commit later.)
93      * @see #getPersistedString
94      *
95      * @hide
96      */
persistStringSet(Set<String> values)97     protected boolean persistStringSet(Set<String> values) {
98         if (shouldPersist()) {
99             // Shouldn't store null
100             if (values.equals(getPersistedStringSet(null))) {
101                 // It's already there, so the same as persisting
102                 return true;
103             }
104 
105             SharedPreferences.Editor editor = getPreferenceManager().getSharedPreferences().edit();
106             editor.putStringSet(getKey(), values);
107             SharedPreferencesCompat.EditorCompat.getInstance().apply(editor);
108             return true;
109         }
110         return false;
111     }
112 
113     /**
114      * Attempts to get a persisted set of Strings from the
115      * {@link android.content.SharedPreferences}.
116      * <p>
117      * This will check if this Preference is persistent, get the SharedPreferences
118      * from the {@link android.preference.PreferenceManager}, and get the value.
119      *
120      * @param defaultReturnValue The default value to return if either the
121      *            Preference is not persistent or the Preference is not in the
122      *            shared preferences.
123      * @return The value from the SharedPreferences or the default return
124      *         value.
125      * @see #persistStringSet(Set)
126      *
127      * @hide
128      */
getPersistedStringSet(Set<String> defaultReturnValue)129     protected Set<String> getPersistedStringSet(Set<String> defaultReturnValue) {
130         if (!shouldPersist()) {
131             return defaultReturnValue;
132         }
133 
134         return getPreferenceManager().getSharedPreferences()
135                 .getStringSet(getKey(), defaultReturnValue);
136     }
137 
138     /**
139      * Sets the human-readable entries to be shown in the list. This will be
140      * shown in subsequent dialogs.
141      * <p>
142      * Each entry must have a corresponding index in
143      * {@link #setEntryValues(CharSequence[])}.
144      *
145      * @param entries The entries.
146      * @see #setEntryValues(CharSequence[])
147      */
setEntries(CharSequence[] entries)148     public void setEntries(CharSequence[] entries) {
149         mEntries = entries;
150     }
151 
152     /**
153      * @see #setEntries(CharSequence[])
154      * @param entriesResId The entries array as a resource.
155      */
setEntries(@rrayRes int entriesResId)156     public void setEntries(@ArrayRes int entriesResId) {
157         setEntries(getContext().getResources().getTextArray(entriesResId));
158     }
159 
160     /**
161      * The list of entries to be shown in the list in subsequent dialogs.
162      *
163      * @return The list as an array.
164      */
getEntries()165     public CharSequence[] getEntries() {
166         return mEntries;
167     }
168 
169     /**
170      * The array to find the value to save for a preference when an entry from
171      * entries is selected. If a user clicks on the second item in entries, the
172      * second item in this array will be saved to the preference.
173      *
174      * @param entryValues The array to be used as values to save for the preference.
175      */
setEntryValues(CharSequence[] entryValues)176     public void setEntryValues(CharSequence[] entryValues) {
177         mEntryValues = entryValues;
178     }
179 
180     /**
181      * @see #setEntryValues(CharSequence[])
182      * @param entryValuesResId The entry values array as a resource.
183      */
setEntryValues(@rrayRes int entryValuesResId)184     public void setEntryValues(@ArrayRes int entryValuesResId) {
185         setEntryValues(getContext().getResources().getTextArray(entryValuesResId));
186     }
187 
188     /**
189      * Returns the array of values to be saved for the preference.
190      *
191      * @return The array of values.
192      */
getEntryValues()193     public CharSequence[] getEntryValues() {
194         return mEntryValues;
195     }
196 
197     /**
198      * Sets the value of the key. This should contain entries in
199      * {@link #getEntryValues()}.
200      *
201      * @param values The values to set for the key.
202      */
setValues(Set<String> values)203     public void setValues(Set<String> values) {
204         mValues.clear();
205         mValues.addAll(values);
206 
207         persistStringSet(values);
208     }
209 
210     /**
211      * Retrieves the current value of the key.
212      */
getValues()213     public Set<String> getValues() {
214         return mValues;
215     }
216 
217     /**
218      * Returns the index of the given value (in the entry values array).
219      *
220      * @param value The value whose index should be returned.
221      * @return The index of the value, or -1 if not found.
222      */
findIndexOfValue(String value)223     public int findIndexOfValue(String value) {
224         if (value != null && mEntryValues != null) {
225             for (int i = mEntryValues.length - 1; i >= 0; i--) {
226                 if (mEntryValues[i].equals(value)) {
227                     return i;
228                 }
229             }
230         }
231         return -1;
232     }
233 
getSelectedItems()234     protected boolean[] getSelectedItems() {
235         final CharSequence[] entries = mEntryValues;
236         final int entryCount = entries.length;
237         final Set<String> values = mValues;
238         boolean[] result = new boolean[entryCount];
239 
240         for (int i = 0; i < entryCount; i++) {
241             result[i] = values.contains(entries[i].toString());
242         }
243 
244         return result;
245     }
246 
247     @Override
onGetDefaultValue(TypedArray a, int index)248     protected Object onGetDefaultValue(TypedArray a, int index) {
249         final CharSequence[] defaultValues = a.getTextArray(index);
250         final Set<String> result = new HashSet<>();
251 
252         for (final CharSequence defaultValue : defaultValues) {
253             result.add(defaultValue.toString());
254         }
255 
256         return result;
257     }
258 
259     @Override
onSetInitialValue(boolean restoreValue, Object defaultValue)260     protected void onSetInitialValue(boolean restoreValue, Object defaultValue) {
261         setValues(restoreValue ? getPersistedStringSet(mValues) : (Set<String>) defaultValue);
262     }
263 
264     @Override
onSaveInstanceState()265     protected Parcelable onSaveInstanceState() {
266         final Parcelable superState = super.onSaveInstanceState();
267         if (isPersistent()) {
268             // No need to save instance state
269             return superState;
270         }
271 
272         final SavedState myState = new SavedState(superState);
273         myState.values = getValues();
274         return myState;
275     }
276 
277     @Override
onRestoreInstanceState(Parcelable state)278     protected void onRestoreInstanceState(Parcelable state) {
279         if (state == null || !state.getClass().equals(SavedState.class)) {
280             // Didn't save state for us in onSaveInstanceState
281             super.onRestoreInstanceState(state);
282             return;
283         }
284 
285         SavedState myState = (SavedState) state;
286         super.onRestoreInstanceState(myState.getSuperState());
287         setValues(myState.values);
288     }
289 
290     private static class SavedState extends BaseSavedState {
291         Set<String> values;
292 
SavedState(Parcel source)293         public SavedState(Parcel source) {
294             super(source);
295             final int size = source.readInt();
296             values = new HashSet<>();
297             String[] strings = new String[size];
298             source.readStringArray(strings);
299 
300             Collections.addAll(values, strings);
301         }
302 
SavedState(Parcelable superState)303         public SavedState(Parcelable superState) {
304             super(superState);
305         }
306 
307         @Override
writeToParcel(@onNull Parcel dest, int flags)308         public void writeToParcel(@NonNull Parcel dest, int flags) {
309             super.writeToParcel(dest, flags);
310             dest.writeInt(values.size());
311             dest.writeStringArray(values.toArray(new String[values.size()]));
312         }
313 
314         public static final Parcelable.Creator<SavedState> CREATOR =
315                 new Parcelable.Creator<SavedState>() {
316                     public SavedState createFromParcel(Parcel in) {
317                         return new SavedState(in);
318                     }
319 
320                     public SavedState[] newArray(int size) {
321                         return new SavedState[size];
322                     }
323                 };
324     }
325 }
326