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      1 /*
      2  * Copyright 2017, 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.managedprovisioning.common;
     17 
     18 import static android.view.accessibility.AccessibilityNodeInfo.AccessibilityAction.ACTION_CLICK;
     19 
     20 import android.app.Activity;
     21 import android.support.annotation.NonNull;
     22 import android.support.annotation.Nullable;
     23 import android.text.Spanned;
     24 import android.text.style.ClickableSpan;
     25 import android.view.ContextMenu;
     26 import android.view.View;
     27 import android.view.accessibility.AccessibilityManager;
     28 import android.view.accessibility.AccessibilityNodeInfo;
     29 import android.widget.TextView;
     30 
     31 import com.android.managedprovisioning.R;
     32 
     33 /**
     34  * Creates a new {@link ContextMenu}, and populates it with a list of links contained in a target
     35  * {@link TextView}.
     36  * <p>
     37  * Known issue: does not listen to TalkBack on / off events.
     38  */
     39 public class AccessibilityContextMenuMaker {
     40     private final Activity mActivity;
     41 
     42     /**
     43      * @param activity the target {@link TextView} belongs to
     44      */
     45     public AccessibilityContextMenuMaker(Activity activity) {
     46         mActivity = activity;
     47     }
     48 
     49     /**
     50      * If {@link ClickableSpan} links present, registers a context menu with the {@link Activity}.
     51      * If no links present, unregisters, which is useful in case of recyclable views.
     52      *
     53      * @param textView target TextView potentially containing links.
     54      */
     55     public void registerWithActivity(TextView textView) {
     56         if (getSpans(getText(textView)).length == 0) {
     57             mActivity.unregisterForContextMenu(textView);
     58             textView.setAccessibilityDelegate(null);
     59             textView.setClickable(false);
     60             textView.setLongClickable(false);
     61             return;
     62         }
     63 
     64         mActivity.registerForContextMenu(textView);
     65         textView.setOnClickListener(View::showContextMenu);
     66         textView.setLongClickable(false);
     67         textView.setAccessibilityDelegate(
     68                 new View.AccessibilityDelegate() {
     69                     @Override
     70                     public void onInitializeAccessibilityNodeInfo(View host,
     71                             AccessibilityNodeInfo info) {
     72                         super.onInitializeAccessibilityNodeInfo(host, info);
     73                         info.addAction(
     74                                 new AccessibilityNodeInfo.AccessibilityAction(ACTION_CLICK.getId(),
     75                                         textView.getContext().getString(
     76                                                 R.string.access_list_of_links)));
     77                     }
     78                 }
     79         );
     80     }
     81 
     82     /**
     83      * Call inside
     84      * {@link Activity#onCreateContextMenu(ContextMenu, View, ContextMenu.ContextMenuInfo)}
     85      */
     86     public void populateMenuContent(ContextMenu menu, TextView textView) {
     87         if (!isScreenReaderEnabled()) {
     88             return;
     89         }
     90 
     91         Spanned spanned = getText(textView);
     92         ClickableSpan[] spans = getSpans(spanned);
     93 
     94         if (spanned == null || spans.length == 0) {
     95             return;
     96         }
     97 
     98         for (ClickableSpan span : spans) {
     99             int s = spanned.getSpanStart(span);
    100             int t = spanned.getSpanEnd(span);
    101             menu.add(spanned.subSequence(s, t)).setOnMenuItemClickListener(menuItem -> {
    102                 span.onClick(textView);
    103                 return false;
    104             });
    105         }
    106         menu.add(R.string.close_list).setOnMenuItemClickListener(menuItem -> {
    107             menu.close();
    108             return false;
    109         });
    110     }
    111 
    112     private boolean isScreenReaderEnabled() {
    113         AccessibilityManager am = mActivity.getSystemService(AccessibilityManager.class);
    114         return am.isEnabled() && am.isTouchExplorationEnabled();
    115     }
    116 
    117     private @Nullable Spanned getText(TextView textView) {
    118         CharSequence text = textView.getText();
    119         return (text instanceof Spanned) ? (Spanned) text : null;
    120     }
    121 
    122     private @NonNull ClickableSpan[] getSpans(Spanned spanned) {
    123         if (spanned == null) {
    124             return new ClickableSpan[0];
    125         }
    126         ClickableSpan[] spans = spanned.getSpans(0, spanned.length(), ClickableSpan.class);
    127         return spans.length == 0 ? new ClickableSpan[0] : spans;
    128     }
    129 }