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diff --git a/java/src/com/android/inputmethod/accessibility/AccessibilityEntityProvider.java b/java/src/com/android/inputmethod/accessibility/AccessibilityEntityProvider.java
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+/*
+ * Copyright (C) 2012 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.graphics.Rect;
+import android.inputmethodservice.InputMethodService;
+import android.os.Bundle;
+import android.os.SystemClock;
+import android.support.v4.view.ViewCompat;
+import android.support.v4.view.accessibility.AccessibilityEventCompat;
+import android.support.v4.view.accessibility.AccessibilityNodeInfoCompat;
+import android.support.v4.view.accessibility.AccessibilityNodeProviderCompat;
+import android.support.v4.view.accessibility.AccessibilityRecordCompat;
+import android.util.Log;
+import android.util.SparseArray;
+import android.view.MotionEvent;
+import android.view.View;
+import android.view.accessibility.AccessibilityEvent;
+import android.view.inputmethod.EditorInfo;
+
+import com.android.inputmethod.keyboard.Key;
+import com.android.inputmethod.keyboard.Keyboard;
+import com.android.inputmethod.keyboard.KeyboardView;
+
+/**
+ * Exposes a virtual view sub-tree for {@link KeyboardView} and generates
+ * {@link AccessibilityEvent}s for individual {@link Key}s.
+ * <p>
+ * A virtual sub-tree is composed of imaginary {@link View}s that are reported
+ * as a part of the view hierarchy for accessibility purposes. This enables
+ * custom views that draw complex content to report them selves as a tree of
+ * virtual views, thus conveying their logical structure.
+ * </p>
+ */
+public class AccessibilityEntityProvider extends AccessibilityNodeProviderCompat {
+    private static final String TAG = AccessibilityEntityProvider.class.getSimpleName();
+    private static final int UNDEFINED = Integer.MIN_VALUE;
+
+    private final InputMethodService mInputMethodService;
+    private final KeyCodeDescriptionMapper mKeyCodeDescriptionMapper;
+    private final AccessibilityUtils mAccessibilityUtils;
+
+    /** A map of integer IDs to {@link Key}s. */
+    private final SparseArray<Key> mVirtualViewIdToKey = new SparseArray<Key>();
+
+    /** Temporary rect used to calculate in-screen bounds. */
+    private final Rect mTempBoundsInScreen = new Rect();
+
+    /** The parent view's cached on-screen location. */
+    private final int[] mParentLocation = new int[2];
+
+    /** The virtual view identifier for the focused node. */
+    private int mAccessibilityFocusedView = UNDEFINED;
+
+    /** The current keyboard view. */
+    private KeyboardView mKeyboardView;
+
+    public AccessibilityEntityProvider(KeyboardView keyboardView, InputMethodService inputMethod) {
+        mInputMethodService = inputMethod;
+
+        mKeyCodeDescriptionMapper = KeyCodeDescriptionMapper.getInstance();
+        mAccessibilityUtils = AccessibilityUtils.getInstance();
+
+        setView(keyboardView);
+    }
+
+    /**
+     * Sets the keyboard view represented by this node provider.
+     *
+     * @param keyboardView The keyboard view to represent.
+     */
+    public void setView(KeyboardView keyboardView) {
+        mKeyboardView = keyboardView;
+        updateParentLocation();
+
+        // Since this class is constructed lazily, we might not get a subsequent
+        // call to setKeyboard() and therefore need to call it now.
+        setKeyboard(mKeyboardView.getKeyboard());
+    }
+
+    /**
+     * Sets the keyboard represented by this node provider.
+     *
+     * @param keyboard The keyboard to represent.
+     */
+    public void setKeyboard(Keyboard keyboard) {
+        assignVirtualViewIds();
+    }
+
+    /**
+     * Creates and populates an {@link AccessibilityEvent} for the specified key
+     * and event type.
+     *
+     * @param key A key on the host keyboard view.
+     * @param eventType The event type to create.
+     * @return A populated {@link AccessibilityEvent} for the key.
+     * @see AccessibilityEvent
+     */
+    public AccessibilityEvent createAccessibilityEvent(Key key, int eventType) {
+        final int virtualViewId = generateVirtualViewIdForKey(key);
+        final String keyDescription = getKeyDescription(key);
+
+        final AccessibilityEvent event = AccessibilityEvent.obtain(eventType);
+        event.setPackageName(mKeyboardView.getContext().getPackageName());
+        event.setClassName(key.getClass().getName());
+        event.setContentDescription(keyDescription);
+        event.setEnabled(true);
+
+        final AccessibilityRecordCompat record = new AccessibilityRecordCompat(event);
+        record.setSource(mKeyboardView, virtualViewId);
+
+        return event;
+    }
+
+    /**
+     * Returns an {@link AccessibilityNodeInfoCompat} representing a virtual
+     * view, i.e. a descendant of the host View, with the given <code>virtualViewId</code> or
+     * the host View itself if <code>virtualViewId</code> equals to {@link View#NO_ID}.
+     * <p>
+     * A virtual descendant is an imaginary View that is reported as a part of
+     * the view hierarchy for accessibility purposes. This enables custom views
+     * that draw complex content to report them selves as a tree of virtual
+     * views, thus conveying their logical structure.
+     * </p>
+     * <p>
+     * The implementer is responsible for obtaining an accessibility node info
+     * from the pool of reusable instances and setting the desired properties of
+     * the node info before returning it.
+     * </p>
+     *
+     * @param virtualViewId A client defined virtual view id.
+     * @return A populated {@link AccessibilityNodeInfoCompat} for a virtual
+     *         descendant or the host View.
+     * @see AccessibilityNodeInfoCompat
+     */
+    @Override
+    public AccessibilityNodeInfoCompat createAccessibilityNodeInfo(int virtualViewId) {
+        AccessibilityNodeInfoCompat info = null;
+
+        if (virtualViewId == UNDEFINED) {
+            return null;
+        } else  if (virtualViewId == View.NO_ID) {
+            // We are requested to create an AccessibilityNodeInfo describing
+            // this View, i.e. the root of the virtual sub-tree.
+            info = AccessibilityNodeInfoCompat.obtain(mKeyboardView);
+            ViewCompat.onInitializeAccessibilityNodeInfo(mKeyboardView, info);
+
+            // Add the virtual children of the root View.
+            final Keyboard keyboard = mKeyboardView.getKeyboard();
+            final Key[] keys = keyboard.mKeys;
+            for (Key key : keys) {
+                final int childVirtualViewId = generateVirtualViewIdForKey(key);
+                info.addChild(mKeyboardView, childVirtualViewId);
+            }
+        } else {
+            // Find the view that corresponds to the given id.
+            final Key key = mVirtualViewIdToKey.get(virtualViewId);
+            if (key == null) {
+                Log.e(TAG, "Invalid virtual view ID: " + virtualViewId);
+                return null;
+            }
+
+            final String keyDescription = getKeyDescription(key);
+            final Rect boundsInParent = key.mHitBox;
+
+            // Calculate the key's in-screen bounds.
+            mTempBoundsInScreen.set(boundsInParent);
+            mTempBoundsInScreen.offset(mParentLocation[0], mParentLocation[1]);
+
+            final Rect boundsInScreen = mTempBoundsInScreen;
+
+            // Obtain and initialize an AccessibilityNodeInfo with
+            // information about the virtual view.
+            info = AccessibilityNodeInfoCompat.obtain();
+            info.setPackageName(mKeyboardView.getContext().getPackageName());
+            info.setClassName(key.getClass().getName());
+            info.setContentDescription(keyDescription);
+            info.setBoundsInParent(boundsInParent);
+            info.setBoundsInScreen(boundsInScreen);
+            info.setParent(mKeyboardView);
+            info.setSource(mKeyboardView, virtualViewId);
+            info.setBoundsInScreen(boundsInScreen);
+            info.setEnabled(true);
+            info.setClickable(true);
+            info.addAction(AccessibilityNodeInfoCompat.ACTION_CLICK);
+
+            if (mAccessibilityFocusedView == virtualViewId) {
+                info.addAction(AccessibilityNodeInfoCompat.ACTION_CLEAR_ACCESSIBILITY_FOCUS);
+            } else {
+                info.addAction(AccessibilityNodeInfoCompat.ACTION_ACCESSIBILITY_FOCUS);
+            }
+        }
+
+        return info;
+    }
+
+    /**
+     * Simulates a key press by injecting touch events into the keyboard view.
+     * This avoids the complexity of trackers and listeners within the keyboard.
+     *
+     * @param key The key to press.
+     */
+    void simulateKeyPress(Key key) {
+        final int x = key.mHitBox.centerX();
+        final int y = key.mHitBox.centerY();
+        final long downTime = SystemClock.uptimeMillis();
+        final MotionEvent downEvent = MotionEvent.obtain(
+                downTime, downTime, MotionEvent.ACTION_DOWN, x, y, 0);
+        final MotionEvent upEvent = MotionEvent.obtain(
+                downTime, SystemClock.uptimeMillis(), MotionEvent.ACTION_UP, x, y, 0);
+
+        mKeyboardView.onTouchEvent(downEvent);
+        mKeyboardView.onTouchEvent(upEvent);
+    }
+
+    @Override
+    public boolean performAction(int virtualViewId, int action, Bundle arguments) {
+        final Key key = mVirtualViewIdToKey.get(virtualViewId);
+
+        if (key == null) {
+            return false;
+        }
+
+        return performActionForKey(key, action, arguments);
+    }
+
+    /**
+     * Performs the specified accessibility action for the given key.
+     *
+     * @param key The on which to perform the action.
+     * @param action The action to perform.
+     * @param arguments The action's arguments.
+     * @return The result of performing the action, or false if the action is
+     *         not supported.
+     */
+    boolean performActionForKey(Key key, int action, Bundle arguments) {
+        final int virtualViewId = generateVirtualViewIdForKey(key);
+
+        switch (action) {
+        case AccessibilityNodeInfoCompat.ACTION_CLICK:
+            simulateKeyPress(key);
+            return true;
+        case AccessibilityNodeInfoCompat.ACTION_ACCESSIBILITY_FOCUS:
+            if (mAccessibilityFocusedView == virtualViewId) {
+                return false;
+            }
+            mAccessibilityFocusedView = virtualViewId;
+            sendAccessibilityEventForKey(
+                    key, AccessibilityEventCompat.TYPE_VIEW_ACCESSIBILITY_FOCUSED);
+            return true;
+        case AccessibilityNodeInfoCompat.ACTION_CLEAR_ACCESSIBILITY_FOCUS:
+            if (mAccessibilityFocusedView != virtualViewId) {
+                return false;
+            }
+            mAccessibilityFocusedView = UNDEFINED;
+            sendAccessibilityEventForKey(
+                    key, AccessibilityEventCompat.TYPE_VIEW_ACCESSIBILITY_FOCUS_CLEARED);
+            return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * Sends an accessibility event for the given {@link Key}.
+     *
+     * @param key The key that's sending the event.
+     * @param eventType The type of event to send.
+     */
+    void sendAccessibilityEventForKey(Key key, int eventType) {
+        final AccessibilityEvent event = createAccessibilityEvent(key, eventType);
+        mAccessibilityUtils.requestSendAccessibilityEvent(event);
+    }
+
+    /**
+     * Returns the context-specific description for a {@link Key}.
+     *
+     * @param key The key to describe.
+     * @return The context-specific description of the key.
+     */
+    private String getKeyDescription(Key key) {
+        final EditorInfo editorInfo = mInputMethodService.getCurrentInputEditorInfo();
+        final boolean shouldObscure = mAccessibilityUtils.shouldObscureInput(editorInfo);
+        final String keyDescription = mKeyCodeDescriptionMapper.getDescriptionForKey(
+                mKeyboardView.getContext(), mKeyboardView.getKeyboard(), key, shouldObscure);
+
+        return keyDescription;
+    }
+
+    /**
+     * Assigns virtual view IDs to keyboard keys and populates the related maps.
+     */
+    private void assignVirtualViewIds() {
+        final Keyboard keyboard = mKeyboardView.getKeyboard();
+        if (keyboard == null) {
+            return;
+        }
+
+        mVirtualViewIdToKey.clear();
+
+        final Key[] keys = keyboard.mKeys;
+        for (Key key : keys) {
+            final int virtualViewId = generateVirtualViewIdForKey(key);
+            mVirtualViewIdToKey.put(virtualViewId, key);
+        }
+    }
+
+    /**
+     * Updates the parent's on-screen location.
+     */
+    private void updateParentLocation() {
+        mKeyboardView.getLocationOnScreen(mParentLocation);
+    }
+
+    /**
+     * Generates a virtual view identifier for the given key. Returned
+     * identifiers are valid until the next global layout state change.
+     *
+     * @param key The key to identify.
+     * @return A virtual view identifier.
+     */
+    private static int generateVirtualViewIdForKey(Key key) {
+        // The key x- and y-coordinates are stable between layout changes.
+        // Generate an identifier by bit-shifting the x-coordinate to the
+        // left-half of the integer and OR'ing with the y-coordinate.
+        return ((0xFFFF & key.mX) << (Integer.SIZE / 2)) | (0xFFFF & key.mY);
+    }
+}