Enable Double R shortcut to reload JS when redbox is shown on Android

Summary: Make "double tap R" shortcut enabled when redbox is shown in RN Android, consistent with that in iOS.

Reviewed By: mkonicek

Differential Revision: D3390132

fbshipit-source-id: 48fc40c2ba371a34abcac42a077359d11e907dfc

ReactAndroid/src/main/java/com/facebook/react/ReactActivity.java

@@ -1,3 +1,12 @@
+/**
+ * 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;
 
 import android.app.Activity;
@@ -12,6 +21,7 @@ import android.widget.Toast;
 
 import com.facebook.common.logging.FLog;
 import com.facebook.react.common.ReactConstants;
+import com.facebook.react.devsupport.DoubleTapReloadRecognizer;
 import com.facebook.react.modules.core.DefaultHardwareBackBtnHandler;
 
 import java.util.List;
@@ -29,7 +39,7 @@ public abstract class ReactActivity extends Activity implements DefaultHardwareB
   private @Nullable ReactInstanceManager mReactInstanceManager;
   private @Nullable ReactRootView mReactRootView;
   private LifecycleState mLifecycleState = LifecycleState.BEFORE_RESUME;
-  private boolean mDoRefresh = false;
+  private DoubleTapReloadRecognizer mDoubleTapReloadRecognizer;
 
   /**
    * Returns the name of the bundle in assets. If this is null, and no file path is specified for
@@ -142,6 +152,7 @@ public abstract class ReactActivity extends Activity implements DefaultHardwareB
     mReactRootView = createRootView();
     mReactRootView.startReactApplication(mReactInstanceManager, getMainComponentName(), getLaunchOptions());
     setContentView(mReactRootView);
+    mDoubleTapReloadRecognizer = new DoubleTapReloadRecognizer();
   }
 
   @Override
@@ -193,22 +204,8 @@ public abstract class ReactActivity extends Activity implements DefaultHardwareB
         mReactInstanceManager.showDevOptionsDialog();
         return true;
       }
-      if (keyCode == KeyEvent.KEYCODE_R && !(getCurrentFocus() instanceof EditText)) {
+      if (mDoubleTapReloadRecognizer.didDoubleTapR(keyCode, getCurrentFocus())) {
-        // Enable double-tap-R-to-reload
+        mReactInstanceManager.getDevSupportManager().handleReloadJS();
-        if (mDoRefresh) {
-          mReactInstanceManager.getDevSupportManager().handleReloadJS();
-          mDoRefresh = false;
-        } else {
-          mDoRefresh = true;
-          new Handler().postDelayed(
-              new Runnable() {
-                @Override
-                public void run() {
-                  mDoRefresh = false;
-                }
-              },
-              200);
-        }
       }
     }
     return super.onKeyUp(keyCode, event);

ReactAndroid/src/main/java/com/facebook/react/devsupport/DoubleTapReloadRecognizer.java

@@ -0,0 +1,44 @@
+/**
+ * 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.devsupport;
+
+import android.os.Handler;
+import android.view.KeyEvent;
+import android.view.View;
+import android.widget.EditText;
+
+/**
+ * A class allows recognizing double key tap of "R", used to reload JS in
+ * {@link AbstractReactActivity}, {@link RedBoxDialog} and {@link ReactActivity}.
+ */
+public class DoubleTapReloadRecognizer {
+  private boolean mDoRefresh = false;
+  private static final long DOUBLE_TAP_DELAY = 200;
+
+  public boolean didDoubleTapR(int keyCode, View view) {
+    if (keyCode == KeyEvent.KEYCODE_R && !(view instanceof EditText)) {
+      if (mDoRefresh) {
+        mDoRefresh = false;
+        return true;
+      } else {
+        mDoRefresh = true;
+        new Handler().postDelayed(
+          new Runnable() {
+            @Override
+            public void run() {
+              mDoRefresh = false;
+            }
+          },
+          DOUBLE_TAP_DELAY);
+      }
+    }
+    return false;
+  }
+}

ReactAndroid/src/main/java/com/facebook/react/devsupport/RedBoxDialog.java

@@ -42,6 +42,7 @@ import org.json.JSONObject;
 /* package */ class RedBoxDialog extends Dialog implements AdapterView.OnItemClickListener {
 
   private final DevSupportManager mDevSupportManager;
+  private final DoubleTapReloadRecognizer mDoubleTapReloadRecognizer;
 
   private ListView mStackView;
   private Button mReloadJs;
@@ -182,6 +183,7 @@ import org.json.JSONObject;
     setContentView(R.layout.redbox_view);
 
     mDevSupportManager = devSupportManager;
+    mDoubleTapReloadRecognizer = new DoubleTapReloadRecognizer();
 
     mStackView = (ListView) findViewById(R.id.rn_redbox_stack);
     mStackView.setOnItemClickListener(this);
@@ -219,7 +221,9 @@ import org.json.JSONObject;
       mDevSupportManager.showDevOptionsDialog();
       return true;
     }
-
+    if (mDoubleTapReloadRecognizer.didDoubleTapR(keyCode, getCurrentFocus())) {
+      mDevSupportManager.handleReloadJS();
+    }
     return super.onKeyUp(keyCode, event);
   }
 }