Added support for touch exploration to Latin IME.

Bug: 4379983
Change-Id: I97f22e54827c6229054b514801401ffa5b4ed3b8

1 files changed, 129 insertions, 0 deletions

diff --git a/java/src/com/android/inputmethod/accessibility/AccessibleInputMethodServiceProxy.java b/java/src/com/android/inputmethod/accessibility/AccessibleInputMethodServiceProxy.java
new file mode 100644
index 000000000..043266c70
--- /dev/null
+++ b/java/src/com/android/inputmethod/accessibility/AccessibleInputMethodServiceProxy.java
@@ -0,0 +1,129 @@
+/*
+ * 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.SharedPreferences;
+import android.inputmethodservice.InputMethodService;
+import android.os.Handler;
+import android.os.Looper;
+import android.os.Message;
+import android.text.TextUtils;
+import android.view.inputmethod.ExtractedText;
+import android.view.inputmethod.ExtractedTextRequest;
+
+import com.android.inputmethod.latin.R;
+
+public class AccessibleInputMethodServiceProxy implements AccessibleKeyboardActionListener {
+    private static final AccessibleInputMethodServiceProxy sInstance =
+            new AccessibleInputMethodServiceProxy();
+
+    /*
+     * Delay for the handler event that's fired when Accessibility is on and the
+     * user hovers outside of any valid keys. This is used to let the user know
+     * that if they lift their finger, nothing will be typed.
+     */
+    private static final long DELAY_NO_HOVER_SELECTION = 250;
+
+    private InputMethodService mInputMethod;
+
+    private AccessibilityHandler mAccessibilityHandler;
+
+    private class AccessibilityHandler extends Handler {
+        private static final int MSG_NO_HOVER_SELECTION = 0;
+
+        public AccessibilityHandler(Looper looper) {
+            super(looper);
+        }
+
+        @Override
+        public void handleMessage(Message msg) {
+            switch (msg.what) {
+            case MSG_NO_HOVER_SELECTION:
+                notifyNoHoverSelection();
+                break;
+            }
+        }
+
+        public void postNoHoverSelection() {
+            removeMessages(MSG_NO_HOVER_SELECTION);
+            sendEmptyMessageDelayed(MSG_NO_HOVER_SELECTION, DELAY_NO_HOVER_SELECTION);
+        }
+
+        public void cancelNoHoverSelection() {
+            removeMessages(MSG_NO_HOVER_SELECTION);
+        }
+    }
+
+    public static void init(InputMethodService inputMethod, SharedPreferences prefs) {
+        sInstance.initInternal(inputMethod, prefs);
+    }
+
+    public static AccessibleInputMethodServiceProxy getInstance() {
+        return sInstance;
+    }
+
+    private AccessibleInputMethodServiceProxy() {
+        // Not publicly instantiable.
+    }
+
+    private void initInternal(InputMethodService inputMethod, SharedPreferences prefs) {
+        mInputMethod = inputMethod;
+        mAccessibilityHandler = new AccessibilityHandler(inputMethod.getMainLooper());
+    }
+
+    /**
+     * If touch exploration is enabled, cancels the event sent by
+     * {@link AccessibleInputMethodServiceProxy#onHoverExit(int)} because the
+     * user is currently hovering above a key.
+     */
+    @Override
+    public void onHoverEnter(int primaryCode) {
+        mAccessibilityHandler.cancelNoHoverSelection();
+    }
+
+    /**
+     * If touch exploration is enabled, sends a delayed event to notify the user
+     * that they are not currently hovering above a key.
+     */
+    @Override
+    public void onHoverExit(int primaryCode) {
+        mAccessibilityHandler.postNoHoverSelection();
+    }
+
+    /**
+     * When Accessibility is turned on, notifies the user that they are not
+     * currently hovering above a key. By default this will speak the currently
+     * entered text.
+     */
+    private void notifyNoHoverSelection() {
+        final ExtractedText extracted = mInputMethod.getCurrentInputConnection().getExtractedText(
+                new ExtractedTextRequest(), 0);
+
+        if (extracted == null)
+            return;
+
+        final CharSequence text;
+
+        if (TextUtils.isEmpty(extracted.text)) {
+            text = mInputMethod.getString(R.string.spoken_no_text_entered);
+        } else {
+            text = mInputMethod.getString(R.string.spoken_current_text_is, extracted.text);
+        }
+
+        AccessibilityUtils.getInstance().speak(text);
+    }
+}