Android:Make MessageQueueThreadImpl startNewBackgroundThread more eff…

ReactAndroid/src/main/java/com/facebook/react/bridge/queue/MessageQueueHandlerThread.java

@@ -0,0 +1,49 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+package com.facebook.react.bridge.queue;
+
+import android.os.Looper;
+import android.os.Process;
+
+class MessageQueueHandlerThread extends Thread {
+  private Looper mLooper;
+
+  protected MessageQueueHandlerThread(String name, long stackSize) {
+    super(null, null, name, stackSize);
+  }
+
+  @Override
+  public void run() {
+    Process.setThreadPriority(Process.THREAD_PRIORITY_DISPLAY);
+    Looper.prepare();
+    synchronized (this) {
+      mLooper = Looper.myLooper();
+      notifyAll();
+    }
+    Looper.loop();
+  }
+
+
+  public Looper getLooper() {
+    if (!isAlive()) {
+      return null;
+    }
+
+    synchronized (this) {
+      while (isAlive() && mLooper == null) {
+        try {
+          wait();
+        } catch (InterruptedException e) {
+        }
+      }
+    }
+    return mLooper;
+  }
+}

ReactAndroid/src/main/java/com/facebook/react/bridge/queue/MessageQueueThreadImpl.java

@@ -179,24 +179,11 @@ public void run() {
    * When this method exits, the new MessageQueueThreadImpl is ready to receive events.
    */
   private static MessageQueueThreadImpl startNewBackgroundThread(
-      final String name,
-      long stackSize,
-      QueueThreadExceptionHandler exceptionHandler) {
-    final SimpleSettableFuture<Looper> looperFuture = new SimpleSettableFuture<>();
-    Thread bgThread = new Thread(null,
-        new Runnable() {
-          @Override
-          public void run() {
-            Process.setThreadPriority(Process.THREAD_PRIORITY_DISPLAY);
-            Looper.prepare();
-
-            looperFuture.set(Looper.myLooper());
-            Looper.loop();
-          }
-        }, "mqt_" + name, stackSize);
-    bgThread.start();
-
-    Looper myLooper = looperFuture.getOrThrow();
-    return new MessageQueueThreadImpl(name, myLooper, exceptionHandler);
+    final String name,
+    long stackSize,
+    QueueThreadExceptionHandler exceptionHandler) {
+    MessageQueueHandlerThread messageQueueHandlerThread = new MessageQueueHandlerThread("mqt_" + name, stackSize);
+    messageQueueHandlerThread.start();
+    return new MessageQueueThreadImpl(name, messageQueueHandlerThread.getLooper(), exceptionHandler);
   }
 }