1 /*
2  * Copyright (C) 2008 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 com.android.phone;
18 
19 import android.app.Activity;
20 import android.app.AlertDialog;
21 import android.app.Dialog;
22 import android.app.StatusBarManager;
23 import android.content.BroadcastReceiver;
24 import android.content.Context;
25 import android.content.Intent;
26 import android.content.IntentFilter;
27 import android.content.res.Resources;
28 import android.media.AudioManager;
29 import android.media.ToneGenerator;
30 import android.net.Uri;
31 import android.os.Bundle;
32 import android.os.PersistableBundle;
33 import android.provider.Settings;
34 import android.telecom.PhoneAccount;
35 import android.telephony.CarrierConfigManager;
36 import android.telephony.PhoneNumberUtils;
37 import android.telephony.SubscriptionManager;
38 import android.text.Editable;
39 import android.text.InputType;
40 import android.text.Spannable;
41 import android.text.SpannableString;
42 import android.text.TextUtils;
43 import android.text.TextWatcher;
44 import android.text.method.DialerKeyListener;
45 import android.text.style.TtsSpan;
46 import android.util.Log;
47 import android.view.HapticFeedbackConstants;
48 import android.view.KeyEvent;
49 import android.view.MenuItem;
50 import android.view.MotionEvent;
51 import android.view.View;
52 import android.view.WindowManager;
53 import android.widget.EditText;
54 
55 import com.android.phone.common.dialpad.DialpadKeyButton;
56 import com.android.phone.common.util.ViewUtil;
57 
58 
59 /**
60  * EmergencyDialer is a special dialer that is used ONLY for dialing emergency calls.
61  *
62  * It's a simplified version of the regular dialer (i.e. the TwelveKeyDialer
63  * activity from apps/Contacts) that:
64  *   1. Allows ONLY emergency calls to be dialed
65  *   2. Disallows voicemail functionality
66  *   3. Uses the FLAG_SHOW_WHEN_LOCKED window manager flag to allow this
67  *      activity to stay in front of the keyguard.
68  *
69  * TODO: Even though this is an ultra-simplified version of the normal
70  * dialer, there's still lots of code duplication between this class and
71  * the TwelveKeyDialer class from apps/Contacts.  Could the common code be
72  * moved into a shared base class that would live in the framework?
73  * Or could we figure out some way to move *this* class into apps/Contacts
74  * also?
75  */
76 public class EmergencyDialer extends Activity implements View.OnClickListener,
77         View.OnLongClickListener, View.OnKeyListener, TextWatcher,
78         DialpadKeyButton.OnPressedListener {
79     // Keys used with onSaveInstanceState().
80     private static final String LAST_NUMBER = "lastNumber";
81 
82     // Intent action for this activity.
83     public static final String ACTION_DIAL = "com.android.phone.EmergencyDialer.DIAL";
84 
85     // List of dialer button IDs.
86     private static final int[] DIALER_KEYS = new int[] {
87             R.id.one, R.id.two, R.id.three,
88             R.id.four, R.id.five, R.id.six,
89             R.id.seven, R.id.eight, R.id.nine,
90             R.id.star, R.id.zero, R.id.pound };
91 
92     // Debug constants.
93     private static final boolean DBG = false;
94     private static final String LOG_TAG = "EmergencyDialer";
95 
96     private StatusBarManager mStatusBarManager;
97 
98     /** The length of DTMF tones in milliseconds */
99     private static final int TONE_LENGTH_MS = 150;
100 
101     /** The DTMF tone volume relative to other sounds in the stream */
102     private static final int TONE_RELATIVE_VOLUME = 80;
103 
104     /** Stream type used to play the DTMF tones off call, and mapped to the volume control keys */
105     private static final int DIAL_TONE_STREAM_TYPE = AudioManager.STREAM_DTMF;
106 
107     private static final int BAD_EMERGENCY_NUMBER_DIALOG = 0;
108 
109     // private static final int USER_ACTIVITY_TIMEOUT_WHEN_NO_PROX_SENSOR = 15000; // millis
110 
111     EditText mDigits;
112     private View mDialButton;
113     private View mDelete;
114 
115     private ToneGenerator mToneGenerator;
116     private Object mToneGeneratorLock = new Object();
117 
118     // determines if we want to playback local DTMF tones.
119     private boolean mDTMFToneEnabled;
120 
121     private EmergencyActionGroup mEmergencyActionGroup;
122 
123     // close activity when screen turns off
124     private BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver() {
125         @Override
126         public void onReceive(Context context, Intent intent) {
127             if (Intent.ACTION_SCREEN_OFF.equals(intent.getAction())) {
128                 finishAndRemoveTask();
129             }
130         }
131     };
132 
133     private String mLastNumber; // last number we tried to dial. Used to restore error dialog.
134 
135     @Override
beforeTextChanged(CharSequence s, int start, int count, int after)136     public void beforeTextChanged(CharSequence s, int start, int count, int after) {
137         // Do nothing
138     }
139 
140     @Override
onTextChanged(CharSequence input, int start, int before, int changeCount)141     public void onTextChanged(CharSequence input, int start, int before, int changeCount) {
142         // Do nothing
143     }
144 
145     @Override
afterTextChanged(Editable input)146     public void afterTextChanged(Editable input) {
147         // Check for special sequences, in particular the "**04" or "**05"
148         // sequences that allow you to enter PIN or PUK-related codes.
149         //
150         // But note we *don't* allow most other special sequences here,
151         // like "secret codes" (*#*#<code>#*#*) or IMEI display ("*#06#"),
152         // since those shouldn't be available if the device is locked.
153         //
154         // So we call SpecialCharSequenceMgr.handleCharsForLockedDevice()
155         // here, not the regular handleChars() method.
156         if (SpecialCharSequenceMgr.handleCharsForLockedDevice(this, input.toString(), this)) {
157             // A special sequence was entered, clear the digits
158             mDigits.getText().clear();
159         }
160 
161         updateDialAndDeleteButtonStateEnabledAttr();
162         updateTtsSpans();
163     }
164 
165     @Override
onCreate(Bundle icicle)166     protected void onCreate(Bundle icicle) {
167         super.onCreate(icicle);
168 
169         mStatusBarManager = (StatusBarManager) getSystemService(Context.STATUS_BAR_SERVICE);
170 
171         // Allow this activity to be displayed in front of the keyguard / lockscreen.
172         WindowManager.LayoutParams lp = getWindow().getAttributes();
173         lp.flags |= WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED;
174 
175         // When no proximity sensor is available, use a shorter timeout.
176         // TODO: Do we enable this for non proximity devices any more?
177         // lp.userActivityTimeout = USER_ACTIVITY_TIMEOUT_WHEN_NO_PROX_SENSOR;
178 
179         getWindow().setAttributes(lp);
180 
181         setContentView(R.layout.emergency_dialer);
182 
183         mDigits = (EditText) findViewById(R.id.digits);
184         mDigits.setKeyListener(DialerKeyListener.getInstance());
185         mDigits.setOnClickListener(this);
186         mDigits.setOnKeyListener(this);
187         mDigits.setLongClickable(false);
188         mDigits.setInputType(InputType.TYPE_NULL);
189         maybeAddNumberFormatting();
190 
191         // Check for the presence of the keypad
192         View view = findViewById(R.id.one);
193         if (view != null) {
194             setupKeypad();
195         }
196 
197         mDelete = findViewById(R.id.deleteButton);
198         mDelete.setOnClickListener(this);
199         mDelete.setOnLongClickListener(this);
200 
201         mDialButton = findViewById(R.id.floating_action_button);
202 
203         // Check whether we should show the onscreen "Dial" button and co.
204         // Read carrier config through the public API because PhoneGlobals is not available when we
205         // run as a secondary user.
206         CarrierConfigManager configMgr =
207                 (CarrierConfigManager) getSystemService(Context.CARRIER_CONFIG_SERVICE);
208         PersistableBundle carrierConfig =
209                 configMgr.getConfigForSubId(SubscriptionManager.getDefaultVoiceSubscriptionId());
210         if (carrierConfig.getBoolean(CarrierConfigManager.KEY_SHOW_ONSCREEN_DIAL_BUTTON_BOOL)) {
211             mDialButton.setOnClickListener(this);
212         } else {
213             mDialButton.setVisibility(View.GONE);
214         }
215         ViewUtil.setupFloatingActionButton(mDialButton, getResources());
216 
217         if (icicle != null) {
218             super.onRestoreInstanceState(icicle);
219         }
220 
221         // Extract phone number from intent
222         Uri data = getIntent().getData();
223         if (data != null && (PhoneAccount.SCHEME_TEL.equals(data.getScheme()))) {
224             String number = PhoneNumberUtils.getNumberFromIntent(getIntent(), this);
225             if (number != null) {
226                 mDigits.setText(number);
227             }
228         }
229 
230         // if the mToneGenerator creation fails, just continue without it.  It is
231         // a local audio signal, and is not as important as the dtmf tone itself.
232         synchronized (mToneGeneratorLock) {
233             if (mToneGenerator == null) {
234                 try {
235                     mToneGenerator = new ToneGenerator(DIAL_TONE_STREAM_TYPE, TONE_RELATIVE_VOLUME);
236                 } catch (RuntimeException e) {
237                     Log.w(LOG_TAG, "Exception caught while creating local tone generator: " + e);
238                     mToneGenerator = null;
239                 }
240             }
241         }
242 
243         final IntentFilter intentFilter = new IntentFilter();
244         intentFilter.addAction(Intent.ACTION_SCREEN_OFF);
245         registerReceiver(mBroadcastReceiver, intentFilter);
246 
247         mEmergencyActionGroup = (EmergencyActionGroup) findViewById(R.id.emergency_action_group);
248     }
249 
250     @Override
onDestroy()251     protected void onDestroy() {
252         super.onDestroy();
253         synchronized (mToneGeneratorLock) {
254             if (mToneGenerator != null) {
255                 mToneGenerator.release();
256                 mToneGenerator = null;
257             }
258         }
259         unregisterReceiver(mBroadcastReceiver);
260     }
261 
262     @Override
onRestoreInstanceState(Bundle icicle)263     protected void onRestoreInstanceState(Bundle icicle) {
264         mLastNumber = icicle.getString(LAST_NUMBER);
265     }
266 
267     @Override
onSaveInstanceState(Bundle outState)268     protected void onSaveInstanceState(Bundle outState) {
269         super.onSaveInstanceState(outState);
270         outState.putString(LAST_NUMBER, mLastNumber);
271     }
272 
273     /**
274      * Explicitly turn off number formatting, since it gets in the way of the emergency
275      * number detector
276      */
maybeAddNumberFormatting()277     protected void maybeAddNumberFormatting() {
278         // Do nothing.
279     }
280 
281     @Override
onPostCreate(Bundle savedInstanceState)282     protected void onPostCreate(Bundle savedInstanceState) {
283         super.onPostCreate(savedInstanceState);
284 
285         // This can't be done in onCreate(), since the auto-restoring of the digits
286         // will play DTMF tones for all the old digits if it is when onRestoreSavedInstanceState()
287         // is called. This method will be called every time the activity is created, and
288         // will always happen after onRestoreSavedInstanceState().
289         mDigits.addTextChangedListener(this);
290     }
291 
setupKeypad()292     private void setupKeypad() {
293         // Setup the listeners for the buttons
294         for (int id : DIALER_KEYS) {
295             final DialpadKeyButton key = (DialpadKeyButton) findViewById(id);
296             key.setOnPressedListener(this);
297         }
298 
299         View view = findViewById(R.id.zero);
300         view.setOnLongClickListener(this);
301     }
302 
303     /**
304      * handle key events
305      */
306     @Override
onKeyDown(int keyCode, KeyEvent event)307     public boolean onKeyDown(int keyCode, KeyEvent event) {
308         switch (keyCode) {
309             // Happen when there's a "Call" hard button.
310             case KeyEvent.KEYCODE_CALL: {
311                 if (TextUtils.isEmpty(mDigits.getText().toString())) {
312                     // if we are adding a call from the InCallScreen and the phone
313                     // number entered is empty, we just close the dialer to expose
314                     // the InCallScreen under it.
315                     finish();
316                 } else {
317                     // otherwise, we place the call.
318                     placeCall();
319                 }
320                 return true;
321             }
322         }
323         return super.onKeyDown(keyCode, event);
324     }
325 
keyPressed(int keyCode)326     private void keyPressed(int keyCode) {
327         mDigits.performHapticFeedback(HapticFeedbackConstants.VIRTUAL_KEY);
328         KeyEvent event = new KeyEvent(KeyEvent.ACTION_DOWN, keyCode);
329         mDigits.onKeyDown(keyCode, event);
330     }
331 
332     @Override
onKey(View view, int keyCode, KeyEvent event)333     public boolean onKey(View view, int keyCode, KeyEvent event) {
334         switch (view.getId()) {
335             case R.id.digits:
336                 // Happen when "Done" button of the IME is pressed. This can happen when this
337                 // Activity is forced into landscape mode due to a desk dock.
338                 if (keyCode == KeyEvent.KEYCODE_ENTER
339                         && event.getAction() == KeyEvent.ACTION_UP) {
340                     placeCall();
341                     return true;
342                 }
343                 break;
344         }
345         return false;
346     }
347 
348     @Override
dispatchTouchEvent(MotionEvent ev)349     public boolean dispatchTouchEvent(MotionEvent ev) {
350         mEmergencyActionGroup.onPreTouchEvent(ev);
351         boolean handled = super.dispatchTouchEvent(ev);
352         mEmergencyActionGroup.onPostTouchEvent(ev);
353         return handled;
354     }
355 
356     @Override
onClick(View view)357     public void onClick(View view) {
358         switch (view.getId()) {
359             case R.id.deleteButton: {
360                 keyPressed(KeyEvent.KEYCODE_DEL);
361                 return;
362             }
363             case R.id.floating_action_button: {
364                 view.performHapticFeedback(HapticFeedbackConstants.VIRTUAL_KEY);
365                 placeCall();
366                 return;
367             }
368             case R.id.digits: {
369                 if (mDigits.length() != 0) {
370                     mDigits.setCursorVisible(true);
371                 }
372                 return;
373             }
374         }
375     }
376 
377     @Override
onPressed(View view, boolean pressed)378     public void onPressed(View view, boolean pressed) {
379         if (!pressed) {
380             return;
381         }
382         switch (view.getId()) {
383             case R.id.one: {
384                 playTone(ToneGenerator.TONE_DTMF_1);
385                 keyPressed(KeyEvent.KEYCODE_1);
386                 return;
387             }
388             case R.id.two: {
389                 playTone(ToneGenerator.TONE_DTMF_2);
390                 keyPressed(KeyEvent.KEYCODE_2);
391                 return;
392             }
393             case R.id.three: {
394                 playTone(ToneGenerator.TONE_DTMF_3);
395                 keyPressed(KeyEvent.KEYCODE_3);
396                 return;
397             }
398             case R.id.four: {
399                 playTone(ToneGenerator.TONE_DTMF_4);
400                 keyPressed(KeyEvent.KEYCODE_4);
401                 return;
402             }
403             case R.id.five: {
404                 playTone(ToneGenerator.TONE_DTMF_5);
405                 keyPressed(KeyEvent.KEYCODE_5);
406                 return;
407             }
408             case R.id.six: {
409                 playTone(ToneGenerator.TONE_DTMF_6);
410                 keyPressed(KeyEvent.KEYCODE_6);
411                 return;
412             }
413             case R.id.seven: {
414                 playTone(ToneGenerator.TONE_DTMF_7);
415                 keyPressed(KeyEvent.KEYCODE_7);
416                 return;
417             }
418             case R.id.eight: {
419                 playTone(ToneGenerator.TONE_DTMF_8);
420                 keyPressed(KeyEvent.KEYCODE_8);
421                 return;
422             }
423             case R.id.nine: {
424                 playTone(ToneGenerator.TONE_DTMF_9);
425                 keyPressed(KeyEvent.KEYCODE_9);
426                 return;
427             }
428             case R.id.zero: {
429                 playTone(ToneGenerator.TONE_DTMF_0);
430                 keyPressed(KeyEvent.KEYCODE_0);
431                 return;
432             }
433             case R.id.pound: {
434                 playTone(ToneGenerator.TONE_DTMF_P);
435                 keyPressed(KeyEvent.KEYCODE_POUND);
436                 return;
437             }
438             case R.id.star: {
439                 playTone(ToneGenerator.TONE_DTMF_S);
440                 keyPressed(KeyEvent.KEYCODE_STAR);
441                 return;
442             }
443         }
444     }
445 
446     /**
447      * called for long touch events
448      */
449     @Override
onLongClick(View view)450     public boolean onLongClick(View view) {
451         int id = view.getId();
452         switch (id) {
453             case R.id.deleteButton: {
454                 mDigits.getText().clear();
455                 return true;
456             }
457             case R.id.zero: {
458                 removePreviousDigitIfPossible();
459                 keyPressed(KeyEvent.KEYCODE_PLUS);
460                 return true;
461             }
462         }
463         return false;
464     }
465 
466     @Override
onResume()467     protected void onResume() {
468         super.onResume();
469 
470         // retrieve the DTMF tone play back setting.
471         mDTMFToneEnabled = Settings.System.getInt(getContentResolver(),
472                 Settings.System.DTMF_TONE_WHEN_DIALING, 1) == 1;
473 
474         // if the mToneGenerator creation fails, just continue without it.  It is
475         // a local audio signal, and is not as important as the dtmf tone itself.
476         synchronized (mToneGeneratorLock) {
477             if (mToneGenerator == null) {
478                 try {
479                     mToneGenerator = new ToneGenerator(AudioManager.STREAM_DTMF,
480                             TONE_RELATIVE_VOLUME);
481                 } catch (RuntimeException e) {
482                     Log.w(LOG_TAG, "Exception caught while creating local tone generator: " + e);
483                     mToneGenerator = null;
484                 }
485             }
486         }
487 
488         // Disable the status bar and set the poke lock timeout to medium.
489         // There is no need to do anything with the wake lock.
490         if (DBG) Log.d(LOG_TAG, "disabling status bar, set to long timeout");
491         mStatusBarManager.disable(StatusBarManager.DISABLE_EXPAND);
492 
493         updateDialAndDeleteButtonStateEnabledAttr();
494     }
495 
496     @Override
onPause()497     public void onPause() {
498         // Reenable the status bar and set the poke lock timeout to default.
499         // There is no need to do anything with the wake lock.
500         if (DBG) Log.d(LOG_TAG, "reenabling status bar and closing the dialer");
501         mStatusBarManager.disable(StatusBarManager.DISABLE_NONE);
502 
503         super.onPause();
504 
505         synchronized (mToneGeneratorLock) {
506             if (mToneGenerator != null) {
507                 mToneGenerator.release();
508                 mToneGenerator = null;
509             }
510         }
511     }
512 
513     /**
514      * place the call, but check to make sure it is a viable number.
515      */
placeCall()516     private void placeCall() {
517         mLastNumber = mDigits.getText().toString();
518         if (PhoneNumberUtils.isLocalEmergencyNumber(this, mLastNumber)) {
519             if (DBG) Log.d(LOG_TAG, "placing call to " + mLastNumber);
520 
521             // place the call if it is a valid number
522             if (mLastNumber == null || !TextUtils.isGraphic(mLastNumber)) {
523                 // There is no number entered.
524                 playTone(ToneGenerator.TONE_PROP_NACK);
525                 return;
526             }
527             Intent intent = new Intent(Intent.ACTION_CALL_EMERGENCY);
528             intent.setData(Uri.fromParts(PhoneAccount.SCHEME_TEL, mLastNumber, null));
529             intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
530             startActivity(intent);
531         } else {
532             if (DBG) Log.d(LOG_TAG, "rejecting bad requested number " + mLastNumber);
533 
534             showDialog(BAD_EMERGENCY_NUMBER_DIALOG);
535         }
536         mDigits.getText().delete(0, mDigits.getText().length());
537     }
538 
539     /**
540      * Plays the specified tone for TONE_LENGTH_MS milliseconds.
541      *
542      * The tone is played locally, using the audio stream for phone calls.
543      * Tones are played only if the "Audible touch tones" user preference
544      * is checked, and are NOT played if the device is in silent mode.
545      *
546      * @param tone a tone code from {@link ToneGenerator}
547      */
playTone(int tone)548     void playTone(int tone) {
549         // if local tone playback is disabled, just return.
550         if (!mDTMFToneEnabled) {
551             return;
552         }
553 
554         // Also do nothing if the phone is in silent mode.
555         // We need to re-check the ringer mode for *every* playTone()
556         // call, rather than keeping a local flag that's updated in
557         // onResume(), since it's possible to toggle silent mode without
558         // leaving the current activity (via the ENDCALL-longpress menu.)
559         AudioManager audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
560         int ringerMode = audioManager.getRingerMode();
561         if ((ringerMode == AudioManager.RINGER_MODE_SILENT)
562             || (ringerMode == AudioManager.RINGER_MODE_VIBRATE)) {
563             return;
564         }
565 
566         synchronized (mToneGeneratorLock) {
567             if (mToneGenerator == null) {
568                 Log.w(LOG_TAG, "playTone: mToneGenerator == null, tone: " + tone);
569                 return;
570             }
571 
572             // Start the new tone (will stop any playing tone)
573             mToneGenerator.startTone(tone, TONE_LENGTH_MS);
574         }
575     }
576 
createErrorMessage(String number)577     private CharSequence createErrorMessage(String number) {
578         if (!TextUtils.isEmpty(number)) {
579             String errorString = getString(R.string.dial_emergency_error, number);
580             int startingPosition = errorString.indexOf(number);
581             int endingPosition = startingPosition + number.length();
582             Spannable result = new SpannableString(errorString);
583             PhoneNumberUtils.addTtsSpan(result, startingPosition, endingPosition);
584             return result;
585         } else {
586             return getText(R.string.dial_emergency_empty_error).toString();
587         }
588     }
589 
590     @Override
onCreateDialog(int id)591     protected Dialog onCreateDialog(int id) {
592         AlertDialog dialog = null;
593         if (id == BAD_EMERGENCY_NUMBER_DIALOG) {
594             // construct dialog
595             dialog = new AlertDialog.Builder(this)
596                     .setTitle(getText(R.string.emergency_enable_radio_dialog_title))
597                     .setMessage(createErrorMessage(mLastNumber))
598                     .setPositiveButton(R.string.ok, null)
599                     .setCancelable(true).create();
600 
601             // blur stuff behind the dialog
602             dialog.getWindow().addFlags(WindowManager.LayoutParams.FLAG_BLUR_BEHIND);
603             dialog.getWindow().addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
604         }
605         return dialog;
606     }
607 
608     @Override
onPrepareDialog(int id, Dialog dialog)609     protected void onPrepareDialog(int id, Dialog dialog) {
610         super.onPrepareDialog(id, dialog);
611         if (id == BAD_EMERGENCY_NUMBER_DIALOG) {
612             AlertDialog alert = (AlertDialog) dialog;
613             alert.setMessage(createErrorMessage(mLastNumber));
614         }
615     }
616 
617     @Override
onOptionsItemSelected(MenuItem item)618     public boolean onOptionsItemSelected(MenuItem item) {
619         final int itemId = item.getItemId();
620         if (itemId == android.R.id.home) {
621             onBackPressed();
622             return true;
623         }
624         return super.onOptionsItemSelected(item);
625     }
626 
627     /**
628      * Update the enabledness of the "Dial" and "Backspace" buttons if applicable.
629      */
updateDialAndDeleteButtonStateEnabledAttr()630     private void updateDialAndDeleteButtonStateEnabledAttr() {
631         final boolean notEmpty = mDigits.length() != 0;
632 
633         mDelete.setEnabled(notEmpty);
634     }
635 
636     /**
637      * Remove the digit just before the current position. Used by various long pressed callbacks
638      * to remove the digit that was populated as a result of the short click.
639      */
removePreviousDigitIfPossible()640     private void removePreviousDigitIfPossible() {
641         final int currentPosition = mDigits.getSelectionStart();
642         if (currentPosition > 0) {
643             mDigits.setSelection(currentPosition);
644             mDigits.getText().delete(currentPosition - 1, currentPosition);
645         }
646     }
647 
648     /**
649      * Update the text-to-speech annotations in the edit field.
650      */
updateTtsSpans()651     private void updateTtsSpans() {
652         for (Object o : mDigits.getText().getSpans(0, mDigits.getText().length(), TtsSpan.class)) {
653             mDigits.getText().removeSpan(o);
654         }
655         PhoneNumberUtils.ttsSpanAsPhoneNumber(mDigits.getText(), 0, mDigits.getText().length());
656     }
657 }
658