Propagate connection info to Blimp android UI.

blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java

Index: blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java
diff --git a/blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java b/blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java
index 156160410039f75e9d7096e3ee05d6726f4420a7..72cc3bde438324f3a3e790273ebb27b48b407771 100644
--- a/blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java
+++ b/blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java
@@ -16,6 +16,7 @@ import android.preference.SwitchPreference;
 import android.support.v7.app.AlertDialog;
 
 import org.chromium.base.ContextUtils;
+import org.chromium.base.ThreadUtils;
 import org.chromium.base.VisibleForTesting;
 import org.chromium.base.annotations.CalledByNative;
 import org.chromium.base.annotations.JNINamespace;
@@ -27,6 +28,7 @@ import org.chromium.components.sync.signin.ChromeSigninController;
  */
 @JNINamespace("blimp::client")
 public class AboutBlimpPreferences extends PreferenceFragment {
+    private static final String PREF_ENGINE_INFO = "blimp_engine_info";
     /**
      * If this fragment is waiting for user sign in.
      */
@@ -72,15 +74,24 @@ public class AboutBlimpPreferences extends PreferenceFragment {
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        initializeNative();
         getActivity().setTitle(R.string.blimp_about_blimp_preferences);
-        updateSettingPage();
+
+        PreferenceScreen screen = getPreferenceScreen();
+        if (screen != null) screen.removeAll();
+        addPreferencesFromResource(R.xml.blimp_preferences);
+
+        setupBlimpSwitch();
+        setupAssignerPreferences();
+
+        // Initialize native layer must be called after Java loads the prefrences entries from xml
+        // file.
+        initializeNative();
     }
 
     @Override
     public void onResume() {
         super.onResume();
-        updateSettingPage();
+        setupBlimpSwitch();
     }
 
     @Override
@@ -89,16 +100,6 @@ public class AboutBlimpPreferences extends PreferenceFragment {
         super.onDestroy();
     }
 
-    // Reload the items in preferences list.
-    private void updateSettingPage() {
-        PreferenceScreen screen = getPreferenceScreen();
-        if (screen != null) screen.removeAll();
-        addPreferencesFromResource(R.xml.blimp_preferences);
-
-        setupBlimpSwitch();
-        setupAssignerPreferences();
-    }
-
     /**
      * Setup the switch preference for Blimp.
      */
@@ -236,8 +237,7 @@ public class AboutBlimpPreferences extends PreferenceFragment {
     @VisibleForTesting
     @CalledByNative
     protected void onSignedOut() {
-        // If user signed out, turn off the switch. We also do a sign in state check on
-        // {@link AboutBlimpPreferences#updateSettingPage()}.
+        // If user signed out, turn off the switch. We also do a sign in state check in onResume.
         final SwitchPreference pref =
                 (SwitchPreference) findPreference(PreferencesUtil.PREF_BLIMP_SWITCH);
         pref.setChecked(false);
@@ -260,6 +260,20 @@ public class AboutBlimpPreferences extends PreferenceFragment {
         }
     }
 
+    /**
+     * Setup engine connection info. This entry is not persisted into shared preference.
+     * @param engineInfo The engine IP address if connected to engine, or error string displayed to
+     * the user.
+     */
+    @CalledByNative
+    private void setEngineInfo(String engineInfo) {
+        ThreadUtils.assertOnUiThread();
+
+        Preference pref = findPreference(PREF_ENGINE_INFO);
+        assert pref != null;
+        pref.setSummary(engineInfo);
+    }
+
     @VisibleForTesting
     protected void initializeNative() {
         mNativeBlimpSettingsAndroid = nativeInit();