Don't update the text services locale in the main thread

This is a revised version of I9f8a81d3c9261a6cfc00292b9f5cb06053b9112d

Bug: 6761326
Change-Id: I43a0a65df6e4b6941bd0dca548c4af20b7e5bf58

2 files changed, 42 insertions, 1 deletions

diff --git a/core/java/android/view/textservice/TextServicesManager.java b/core/java/android/view/textservice/TextServicesManager.java
index 81b36db..e0e19b9 100644
--- a/core/java/android/view/textservice/TextServicesManager.java
+++ b/core/java/android/view/textservice/TextServicesManager.java
@@ -217,6 +217,12 @@ public final class TextServicesManager {
     public SpellCheckerSubtype getCurrentSpellCheckerSubtype(
             boolean allowImplicitlySelectedSubtype) {
         try {
+            if (sService == null) {
+                // TODO: This is a workaround. Needs to investigate why sService could be null
+                // here.
+                Log.e(TAG, "sService is null.");
+                return null;
+            }
             // Passing null as a locale until we support multiple enabled spell checker subtypes.
             return sService.getCurrentSpellCheckerSubtype(null, allowImplicitlySelectedSubtype);
         } catch (RemoteException e) {
diff --git a/core/java/android/widget/TextView.java b/core/java/android/widget/TextView.java
index 410a0ca..958b669 100644
--- a/core/java/android/widget/TextView.java
+++ b/core/java/android/widget/TextView.java
@@ -33,6 +33,7 @@ import android.graphics.RectF;
 import android.graphics.Typeface;
 import android.graphics.drawable.Drawable;
 import android.inputmethodservice.ExtractEditText;
+import android.os.AsyncTask;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.Message;
@@ -132,6 +133,7 @@ import java.io.IOException;
 import java.lang.ref.WeakReference;
 import java.util.ArrayList;
 import java.util.Locale;
+import java.util.concurrent.locks.ReentrantLock;
 
 /**
  * Displays text to the user and optionally allows them to edit it.  A TextView
@@ -378,6 +380,9 @@ public class TextView extends View implements ViewTreeObserver.OnPreDrawListener
 
     private InputFilter[] mFilters = NO_FILTERS;
 
+    private volatile Locale mCurrentTextServicesLocaleCache;
+    private final ReentrantLock mCurrentTextServicesLocaleLock = new ReentrantLock();
+
     // It is possible to have a selection even when mEditor is null (programmatically set, like when
     // a link is pressed). These highlight-related fields do not go in mEditor.
     int mHighlightColor = 0x6633B5E5;
@@ -7675,13 +7680,43 @@ public class TextView extends View implements ViewTreeObserver.OnPreDrawListener
 
     /**
      * This is a temporary method. Future versions may support multi-locale text.
+     * Caveat: This method may not return the latest text services locale, but this should be
+     * acceptable and it's more important to make this method asynchronous.
      *
      * @return The locale that should be used for a word iterator and a spell checker
      * in this TextView, based on the current spell checker settings,
      * the current IME's locale, or the system default locale.
      * @hide
      */
+    // TODO: Support multi-locale
+    // TODO: Update the text services locale immediately after the keyboard locale is switched
+    // by catching intent of keyboard switch event
     public Locale getTextServicesLocale() {
+        if (mCurrentTextServicesLocaleCache == null) {
+            // If there is no cached text services locale, just return the default locale.
+            mCurrentTextServicesLocaleCache = Locale.getDefault();
+        }
+        // Start fetching the text services locale asynchronously.
+        updateTextServicesLocaleAsync();
+        return mCurrentTextServicesLocaleCache;
+    }
+
+    private void updateTextServicesLocaleAsync() {
+        AsyncTask.execute(new Runnable() {
+            @Override
+            public void run() {
+                if (mCurrentTextServicesLocaleLock.tryLock()) {
+                    try {
+                        updateTextServicesLocaleLocked();
+                    } finally {
+                        mCurrentTextServicesLocaleLock.unlock();
+                    }
+                }
+            }
+        });
+    }
+
+    private void updateTextServicesLocaleLocked() {
         Locale locale = Locale.getDefault();
         final TextServicesManager textServicesManager = (TextServicesManager)
                 mContext.getSystemService(Context.TEXT_SERVICES_MANAGER_SERVICE);
@@ -7689,7 +7724,7 @@ public class TextView extends View implements ViewTreeObserver.OnPreDrawListener
         if (subtype != null) {
             locale = SpellCheckerSubtype.constructLocaleFromString(subtype.getLocale());
         }
-        return locale;
+        mCurrentTextServicesLocaleCache = locale;
     }
 
     void onLocaleChanged() {