Added support for touch exploration to Latin IME.

Bug: 4379983
Change-Id: I97f22e54827c6229054b514801401ffa5b4ed3b8

1 files changed, 133 insertions, 0 deletions

diff --git a/java/src/com/android/inputmethod/accessibility/AccessibilityUtils.java b/java/src/com/android/inputmethod/accessibility/AccessibilityUtils.java
new file mode 100644
index 000000000..ae614b7e0
--- /dev/null
+++ b/java/src/com/android/inputmethod/accessibility/AccessibilityUtils.java
@@ -0,0 +1,133 @@
+/*
+ * 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.accessibilityservice.AccessibilityServiceInfo;
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.inputmethodservice.InputMethodService;
+import android.os.SystemClock;
+import android.util.Log;
+import android.view.MotionEvent;
+import android.view.accessibility.AccessibilityEvent;
+import android.view.accessibility.AccessibilityManager;
+
+import com.android.inputmethod.compat.AccessibilityEventCompatUtils;
+import com.android.inputmethod.compat.AccessibilityManagerCompatWrapper;
+import com.android.inputmethod.compat.MotionEventCompatUtils;
+
+public 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 AccessibilityManager mAccessibilityManager;
+    private AccessibilityManagerCompatWrapper mCompatManager;
+
+    /*
+     * 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(InputMethodService inputMethod, SharedPreferences prefs) {
+        if (!ENABLE_ACCESSIBILITY)
+            return;
+
+        // These only need to be initialized if the kill switch is off.
+        sInstance.initInternal(inputMethod, prefs);
+        KeyCodeDescriptionMapper.init(inputMethod, prefs);
+        AccessibleInputMethodServiceProxy.init(inputMethod, prefs);
+        AccessibleKeyboardViewProxy.init(inputMethod, prefs);
+    }
+
+    public static AccessibilityUtils getInstance() {
+        return sInstance;
+    }
+
+    private AccessibilityUtils() {
+        // This class is not publicly instantiable.
+    }
+
+    private void initInternal(Context context, SharedPreferences prefs) {
+        mAccessibilityManager = (AccessibilityManager) context
+                .getSystemService(Context.ACCESSIBILITY_SERVICE);
+        mCompatManager = new AccessibilityManagerCompatWrapper(mAccessibilityManager);
+    }
+
+    /**
+     * Returns {@code true} if touch exploration is enabled. Currently, this
+     * means that the kill switch is off, the device supports touch exploration,
+     * and a spoken feedback service is turned on.
+     *
+     * @return {@code true} if touch exploration is enabled.
+     */
+    public boolean isTouchExplorationEnabled() {
+        return ENABLE_ACCESSIBILITY
+                && AccessibilityEventCompatUtils.supportsTouchExploration()
+                && mAccessibilityManager.isEnabled()
+                && !mCompatManager.getEnabledAccessibilityServiceList(
+                        AccessibilityServiceInfo.FEEDBACK_SPOKEN).isEmpty();
+    }
+
+    /**
+     * 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 boolean isTouchExplorationEvent(MotionEvent event) {
+        final int action = event.getAction();
+
+        return action == MotionEventCompatUtils.ACTION_HOVER_ENTER
+                || action == MotionEventCompatUtils.ACTION_HOVER_EXIT
+                || action == MotionEventCompatUtils.ACTION_HOVER_MOVE;
+    }
+
+    /**
+     * Sends the specified text to the {@link AccessibilityManager} to be
+     * spoken.
+     *
+     * @param text the text to speak
+     */
+    public void speak(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(AccessibilityEventCompatUtils.TYPE_VIEW_HOVER_ENTER);
+
+        event.setPackageName(PACKAGE);
+        event.setClassName(CLASS);
+        event.setEventTime(SystemClock.uptimeMillis());
+        event.setEnabled(true);
+        event.getText().add(text);
+
+        mAccessibilityManager.sendAccessibilityEvent(event);
+    }
+}