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      1 /*
      2  * Copyright (C) 2016 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 package com.android.emergency.preferences;
     17 
     18 import android.content.Context;
     19 import android.content.res.TypedArray;
     20 import android.preference.ListPreference;
     21 import android.support.annotation.Nullable;
     22 import android.text.Spannable;
     23 import android.text.SpannableString;
     24 import android.text.TextUtils;
     25 import android.text.style.TtsSpan;
     26 import android.util.AttributeSet;
     27 
     28 import com.android.emergency.R;
     29 import com.android.emergency.ReloadablePreferenceInterface;
     30 import com.android.internal.annotations.VisibleForTesting;
     31 
     32 /**
     33  * Custom {@link ListPreference} that allows us to refresh and update the summary.
     34  */
     35 public class EmergencyListPreference extends ListPreference
     36         implements ReloadablePreferenceInterface {
     37     @Nullable
     38     private CharSequence[] mContentDescriptions;
     39 
     40     public EmergencyListPreference(Context context, AttributeSet attrs) {
     41         super(context, attrs);
     42         TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.EmergencyListPreference);
     43         mContentDescriptions =
     44                 a.getTextArray(R.styleable.EmergencyListPreference_entryContentDescriptions);
     45         a.recycle();
     46 
     47         if (mContentDescriptions != null) {
     48             // Override entries with accessible entries.
     49             setEntries(createAccessibleEntries(getEntries(), mContentDescriptions));
     50         }
     51     }
     52 
     53     @Override
     54     public void reloadFromPreference() {
     55         setValue(getPersistedString(""));
     56     }
     57 
     58     @Override
     59     public boolean isNotSet() {
     60         return TextUtils.isEmpty(getValue());
     61     }
     62 
     63     @Override
     64     public CharSequence getSummary() {
     65         final String value = getValue();
     66         int index = findIndexOfValue(value);
     67         if (index < 0) {
     68             return super.getSummary();
     69         } else {
     70             return getEntry();
     71         }
     72     }
     73 
     74     @Nullable
     75     @VisibleForTesting
     76     CharSequence[] getContentDescriptions() {
     77         return mContentDescriptions;
     78     }
     79 
     80     private static CharSequence[] createAccessibleEntries(CharSequence entries[],
     81                                                           CharSequence[] contentDescriptions) {
     82         CharSequence[] accessibleEntries = new CharSequence[entries.length];
     83         for (int i = 0; i < entries.length; i++) {
     84             accessibleEntries[i] = createAccessibleSequence(entries[i], contentDescriptions[i]);
     85         }
     86         return accessibleEntries;
     87     }
     88 
     89     private static SpannableString createAccessibleSequence(CharSequence displayText,
     90                                                             CharSequence accessibleText) {
     91         SpannableString str = new SpannableString(displayText);
     92         str.setSpan(new TtsSpan.TextBuilder((String) accessibleText).build(), 0,
     93                 displayText.length(),
     94                 Spannable.SPAN_INCLUSIVE_INCLUSIVE);
     95         return str;
     96     }
     97 }
     98