java/src/com/android/inputmethod/accessibility/AccessibilityUtils.java - platform/packages/inputmethods/LatinIME - Git at Google

 /*
  * Copyright (C) 2011 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package com.android.inputmethod.accessibility;

 import android.content.Context;
 import android.media.AudioManager;
 import android.os.Build;
 import android.os.SystemClock;
 import android.provider.Settings;
 import android.support.v4.view.accessibility.AccessibilityEventCompat;
 import android.text.TextUtils;
 import android.util.Log;
 import android.view.MotionEvent;
 import android.view.View;
 import android.view.ViewGroup;
 import android.view.ViewParent;
 import android.view.accessibility.AccessibilityEvent;
 import android.view.accessibility.AccessibilityManager;
 import android.view.inputmethod.EditorInfo;

 import com.android.inputmethod.compat.SettingsSecureCompatUtils;
 import com.android.inputmethod.latin.R;
 import com.android.inputmethod.latin.SuggestedWords;
 import com.android.inputmethod.latin.utils.InputTypeUtils;

 public final class AccessibilityUtils {
     private static final String TAG = AccessibilityUtils.class.getSimpleName();
     private static final String CLASS = AccessibilityUtils.class.getClass().getName();
     private static final String PACKAGE =
             AccessibilityUtils.class.getClass().getPackage().getName();

     private static final AccessibilityUtils sInstance = new AccessibilityUtils();

     private Context mContext;
     private AccessibilityManager mAccessibilityManager;
     private AudioManager mAudioManager;

     /** The most recent auto-correction. */
     private String mAutoCorrectionWord;

     /** The most recent typed word for auto-correction. */
     private String mTypedWord;

     /*
      * Setting this constant to {@code false} will disable all keyboard
      * accessibility code, regardless of whether Accessibility is turned on in
      * the system settings. It should ONLY be used in the event of an emergency.
      */
     private static final boolean ENABLE_ACCESSIBILITY = true;

     public static void init(final Context context) {
         if (!ENABLE_ACCESSIBILITY) return;

         // These only need to be initialized if the kill switch is off.
         sInstance.initInternal(context);
     }

     public static AccessibilityUtils getInstance() {
         return sInstance;
     }

     private AccessibilityUtils() {
         // This class is not publicly instantiable.
     }

     private void initInternal(final Context context) {
         mContext = context;
         mAccessibilityManager =
                 (AccessibilityManager) context.getSystemService(Context.ACCESSIBILITY_SERVICE);
         mAudioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
     }

     /**
      * Returns {@code true} if accessibility is enabled. Currently, this means
      * that the kill switch is off and system accessibility is turned on.
      *
      * @return {@code true} if accessibility is enabled.
      */
     public boolean isAccessibilityEnabled() {
         return ENABLE_ACCESSIBILITY && mAccessibilityManager.isEnabled();
     }

     /**
      * Returns {@code true} if touch exploration is enabled. Currently, this
      * means that the kill switch is off, the device supports touch exploration,
      * and system accessibility is turned on.
      *
      * @return {@code true} if touch exploration is enabled.
      */
     public boolean isTouchExplorationEnabled() {
         return isAccessibilityEnabled() && mAccessibilityManager.isTouchExplorationEnabled();
     }

     /**
      * Returns {@true} if the provided event is a touch exploration (e.g. hover)
      * event. This is used to determine whether the event should be processed by
      * the touch exploration code within the keyboard.
      *
      * @param event The event to check.
      * @return {@true} is the event is a touch exploration event
      */
     public static boolean isTouchExplorationEvent(final MotionEvent event) {
         final int action = event.getAction();
         return action == MotionEvent.ACTION_HOVER_ENTER
                 || action == MotionEvent.ACTION_HOVER_EXIT
                 || action == MotionEvent.ACTION_HOVER_MOVE;
     }

     /**
      * Returns whether the device should obscure typed password characters.
      * Typically this means speaking "dot" in place of non-control characters.
      *
      * @return {@code true} if the device should obscure password characters.
      */
     @SuppressWarnings("deprecation")
     public boolean shouldObscureInput(final EditorInfo editorInfo) {
         if (editorInfo == null) return false;

         // The user can optionally force speaking passwords.
         if (SettingsSecureCompatUtils.ACCESSIBILITY_SPEAK_PASSWORD != null) {
             final boolean speakPassword = Settings.Secure.getInt(mContext.getContentResolver(),
                     SettingsSecureCompatUtils.ACCESSIBILITY_SPEAK_PASSWORD, 0) != 0;
             if (speakPassword) return false;
         }

         // Always speak if the user is listening through headphones.
         if (mAudioManager.isWiredHeadsetOn() || mAudioManager.isBluetoothA2dpOn()) {
             return false;
         }

         // Don't speak if the IME is connected to a password field.
         return InputTypeUtils.isPasswordInputType(editorInfo.inputType);
     }

     /**
      * Sets the current auto-correction word and typed word. These may be used
      * to provide the user with a spoken description of what auto-correction
      * will occur when a key is typed.
      *
      * @param suggestedWords the list of suggested auto-correction words
      */
     public void setAutoCorrection(final SuggestedWords suggestedWords) {
         if (suggestedWords.mWillAutoCorrect) {
             mAutoCorrectionWord = suggestedWords.getWord(SuggestedWords.INDEX_OF_AUTO_CORRECTION);
             final SuggestedWords.SuggestedWordInfo typedWordInfo = suggestedWords.mTypedWordInfo;
             if (null == typedWordInfo) {
                 mTypedWord = null;
             } else {
                 mTypedWord = typedWordInfo.mWord;
             }
         } else {
             mAutoCorrectionWord = null;
             mTypedWord = null;
         }
     }

     /**
      * Obtains a description for an auto-correction key, taking into account the
      * currently typed word and auto-correction.
      *
      * @param keyCodeDescription spoken description of the key that will insert
      *            an auto-correction
      * @param shouldObscure whether the key should be obscured
      * @return a description including a description of the auto-correction, if
      *         needed
      */
     public String getAutoCorrectionDescription(
             final String keyCodeDescription, final boolean shouldObscure) {
         if (!TextUtils.isEmpty(mAutoCorrectionWord)) {
             if (!TextUtils.equals(mAutoCorrectionWord, mTypedWord)) {
                 if (shouldObscure) {
                     // This should never happen, but just in case...
                     return mContext.getString(R.string.spoken_auto_correct_obscured,
                             keyCodeDescription);
                 }
                 return mContext.getString(R.string.spoken_auto_correct, keyCodeDescription,
                         mTypedWord, mAutoCorrectionWord);
             }
         }

         return keyCodeDescription;
     }

     /**
      * Sends the specified text to the {@link AccessibilityManager} to be
      * spoken.
      *
      * @param view The source view.
      * @param text The text to speak.
      */
     public void announceForAccessibility(final View view, final CharSequence text) {
         if (!mAccessibilityManager.isEnabled()) {
             Log.e(TAG, "Attempted to speak when accessibility was disabled!");
             return;
         }

         // The following is a hack to avoid using the heavy-weight TextToSpeech
         // class. Instead, we're just forcing a fake AccessibilityEvent into
         // the screen reader to make it speak.
         final AccessibilityEvent event = AccessibilityEvent.obtain();

         event.setPackageName(PACKAGE);
         event.setClassName(CLASS);
         event.setEventTime(SystemClock.uptimeMillis());
         event.setEnabled(true);
         event.getText().add(text);

         // Platforms starting at SDK version 16 (Build.VERSION_CODES.JELLY_BEAN) should use
         // announce events.
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
             event.setEventType(AccessibilityEventCompat.TYPE_ANNOUNCEMENT);
         } else {
             event.setEventType(AccessibilityEvent.TYPE_VIEW_FOCUSED);
         }

         final ViewParent viewParent = view.getParent();
         if ((viewParent == null) || !(viewParent instanceof ViewGroup)) {
             Log.e(TAG, "Failed to obtain ViewParent in announceForAccessibility");
             return;
         }

         viewParent.requestSendAccessibilityEvent(view, event);
     }

     /**
      * Handles speaking the "connect a headset to hear passwords" notification
      * when connecting to a password field.
      *
      * @param view The source view.
      * @param editorInfo The input connection's editor info attribute.
      * @param restarting Whether the connection is being restarted.
      */
     public void onStartInputViewInternal(final View view, final EditorInfo editorInfo,
             final boolean restarting) {
         if (shouldObscureInput(editorInfo)) {
             final CharSequence text = mContext.getText(R.string.spoken_use_headphones);
             announceForAccessibility(view, text);
         }
     }

     /**
      * Sends the specified {@link AccessibilityEvent} if accessibility is
      * enabled. No operation if accessibility is disabled.
      *
      * @param event The event to send.
      */
     public void requestSendAccessibilityEvent(final AccessibilityEvent event) {
         if (mAccessibilityManager.isEnabled()) {
             mAccessibilityManager.sendAccessibilityEvent(event);
         }
     }
 }
	/*
	* Copyright (C) 2011 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.android.inputmethod.accessibility;

	import android.content.Context;
	import android.media.AudioManager;
	import android.os.Build;
	import android.os.SystemClock;
	import android.provider.Settings;
	import android.support.v4.view.accessibility.AccessibilityEventCompat;
	import android.text.TextUtils;
	import android.util.Log;
	import android.view.MotionEvent;
	import android.view.View;
	import android.view.ViewGroup;
	import android.view.ViewParent;
	import android.view.accessibility.AccessibilityEvent;
	import android.view.accessibility.AccessibilityManager;
	import android.view.inputmethod.EditorInfo;

	import com.android.inputmethod.compat.SettingsSecureCompatUtils;
	import com.android.inputmethod.latin.R;
	import com.android.inputmethod.latin.SuggestedWords;
	import com.android.inputmethod.latin.utils.InputTypeUtils;

	public final class AccessibilityUtils {
	private static final String TAG = AccessibilityUtils.class.getSimpleName();
	private static final String CLASS = AccessibilityUtils.class.getClass().getName();
	private static final String PACKAGE =
	AccessibilityUtils.class.getClass().getPackage().getName();

	private static final AccessibilityUtils sInstance = new AccessibilityUtils();

	private Context mContext;
	private AccessibilityManager mAccessibilityManager;
	private AudioManager mAudioManager;

	/** The most recent auto-correction. */
	private String mAutoCorrectionWord;

	/** The most recent typed word for auto-correction. */
	private String mTypedWord;

	/*
	* Setting this constant to {@code false} will disable all keyboard
	* accessibility code, regardless of whether Accessibility is turned on in
	* the system settings. It should ONLY be used in the event of an emergency.
	*/
	private static final boolean ENABLE_ACCESSIBILITY = true;

	public static void init(final Context context) {
	if (!ENABLE_ACCESSIBILITY) return;

	// These only need to be initialized if the kill switch is off.
	sInstance.initInternal(context);
	}

	public static AccessibilityUtils getInstance() {
	return sInstance;
	}

	private AccessibilityUtils() {
	// This class is not publicly instantiable.
	}

	private void initInternal(final Context context) {
	mContext = context;
	mAccessibilityManager =
	(AccessibilityManager) context.getSystemService(Context.ACCESSIBILITY_SERVICE);
	mAudioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
	}

	/**
	* Returns {@code true} if accessibility is enabled. Currently, this means
	* that the kill switch is off and system accessibility is turned on.
	*
	* @return {@code true} if accessibility is enabled.
	*/
	public boolean isAccessibilityEnabled() {
	return ENABLE_ACCESSIBILITY && mAccessibilityManager.isEnabled();
	}

	/**
	* Returns {@code true} if touch exploration is enabled. Currently, this
	* means that the kill switch is off, the device supports touch exploration,
	* and system accessibility is turned on.
	*
	* @return {@code true} if touch exploration is enabled.
	*/
	public boolean isTouchExplorationEnabled() {
	return isAccessibilityEnabled() && mAccessibilityManager.isTouchExplorationEnabled();
	}

	/**
	* Returns {@true} if the provided event is a touch exploration (e.g. hover)
	* event. This is used to determine whether the event should be processed by
	* the touch exploration code within the keyboard.
	*
	* @param event The event to check.
	* @return {@true} is the event is a touch exploration event
	*/
	public static boolean isTouchExplorationEvent(final MotionEvent event) {
	final int action = event.getAction();
	return action == MotionEvent.ACTION_HOVER_ENTER
	\|\| action == MotionEvent.ACTION_HOVER_EXIT
	\|\| action == MotionEvent.ACTION_HOVER_MOVE;
	}

	/**
	* Returns whether the device should obscure typed password characters.
	* Typically this means speaking "dot" in place of non-control characters.
	*
	* @return {@code true} if the device should obscure password characters.
	*/
	@SuppressWarnings("deprecation")
	public boolean shouldObscureInput(final EditorInfo editorInfo) {
	if (editorInfo == null) return false;

	// The user can optionally force speaking passwords.
	if (SettingsSecureCompatUtils.ACCESSIBILITY_SPEAK_PASSWORD != null) {
	final boolean speakPassword = Settings.Secure.getInt(mContext.getContentResolver(),
	SettingsSecureCompatUtils.ACCESSIBILITY_SPEAK_PASSWORD, 0) != 0;
	if (speakPassword) return false;
	}

	// Always speak if the user is listening through headphones.
	if (mAudioManager.isWiredHeadsetOn() \|\| mAudioManager.isBluetoothA2dpOn()) {
	return false;
	}

	// Don't speak if the IME is connected to a password field.
	return InputTypeUtils.isPasswordInputType(editorInfo.inputType);
	}

	/**
	* Sets the current auto-correction word and typed word. These may be used
	* to provide the user with a spoken description of what auto-correction
	* will occur when a key is typed.
	*
	* @param suggestedWords the list of suggested auto-correction words
	*/
	public void setAutoCorrection(final SuggestedWords suggestedWords) {
	if (suggestedWords.mWillAutoCorrect) {
	mAutoCorrectionWord = suggestedWords.getWord(SuggestedWords.INDEX_OF_AUTO_CORRECTION);
	final SuggestedWords.SuggestedWordInfo typedWordInfo = suggestedWords.mTypedWordInfo;
	if (null == typedWordInfo) {
	mTypedWord = null;
	} else {
	mTypedWord = typedWordInfo.mWord;
	}
	} else {
	mAutoCorrectionWord = null;
	mTypedWord = null;
	}
	}

	/**
	* Obtains a description for an auto-correction key, taking into account the
	* currently typed word and auto-correction.
	*
	* @param keyCodeDescription spoken description of the key that will insert
	* an auto-correction
	* @param shouldObscure whether the key should be obscured
	* @return a description including a description of the auto-correction, if
	* needed
	*/
	public String getAutoCorrectionDescription(
	final String keyCodeDescription, final boolean shouldObscure) {
	if (!TextUtils.isEmpty(mAutoCorrectionWord)) {
	if (!TextUtils.equals(mAutoCorrectionWord, mTypedWord)) {
	if (shouldObscure) {
	// This should never happen, but just in case...
	return mContext.getString(R.string.spoken_auto_correct_obscured,
	keyCodeDescription);
	}
	return mContext.getString(R.string.spoken_auto_correct, keyCodeDescription,
	mTypedWord, mAutoCorrectionWord);
	}
	}

	return keyCodeDescription;
	}

	/**
	* Sends the specified text to the {@link AccessibilityManager} to be
	* spoken.
	*
	* @param view The source view.
	* @param text The text to speak.
	*/
	public void announceForAccessibility(final View view, final CharSequence text) {
	if (!mAccessibilityManager.isEnabled()) {
	Log.e(TAG, "Attempted to speak when accessibility was disabled!");
	return;
	}

	// The following is a hack to avoid using the heavy-weight TextToSpeech
	// class. Instead, we're just forcing a fake AccessibilityEvent into
	// the screen reader to make it speak.
	final AccessibilityEvent event = AccessibilityEvent.obtain();

	event.setPackageName(PACKAGE);
	event.setClassName(CLASS);
	event.setEventTime(SystemClock.uptimeMillis());
	event.setEnabled(true);
	event.getText().add(text);

	// Platforms starting at SDK version 16 (Build.VERSION_CODES.JELLY_BEAN) should use
	// announce events.
	if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
	event.setEventType(AccessibilityEventCompat.TYPE_ANNOUNCEMENT);
	} else {
	event.setEventType(AccessibilityEvent.TYPE_VIEW_FOCUSED);
	}

	final ViewParent viewParent = view.getParent();
	if ((viewParent == null) \|\| !(viewParent instanceof ViewGroup)) {
	Log.e(TAG, "Failed to obtain ViewParent in announceForAccessibility");
	return;
	}

	viewParent.requestSendAccessibilityEvent(view, event);
	}

	/**
	* Handles speaking the "connect a headset to hear passwords" notification
	* when connecting to a password field.
	*
	* @param view The source view.
	* @param editorInfo The input connection's editor info attribute.
	* @param restarting Whether the connection is being restarted.
	*/
	public void onStartInputViewInternal(final View view, final EditorInfo editorInfo,
	final boolean restarting) {
	if (shouldObscureInput(editorInfo)) {
	final CharSequence text = mContext.getText(R.string.spoken_use_headphones);
	announceForAccessibility(view, text);
	}
	}

	/**
	* Sends the specified {@link AccessibilityEvent} if accessibility is
	* enabled. No operation if accessibility is disabled.
	*
	* @param event The event to send.
	*/
	public void requestSendAccessibilityEvent(final AccessibilityEvent event) {
	if (mAccessibilityManager.isEnabled()) {
	mAccessibilityManager.sendAccessibilityEvent(event);
	}
	}
	}