Integration of Android apps into Facebook Messenger

I am trying to integrate the Facebook Messenger platform into my android app.

FacebookSdk.sdkInitialize(getApplicationContext());
String mimeType = "image/jpeg";
String metadata = "{ \"type\": \"event\" }";
ShareToMessengerParams shareToMessengerParams = ShareToMessengerParams
    .newBuilder(Uri.fromFile(new File("/sdcard/Images/img.jpg")), mimeType)
    .setMetaData(metadata)
    .build();
MessengerUtils.shareToMessenger(this, 1, shareToMessengerParams);

      

        
        
        
      

    

Content from AndroidManifest.xml

<intent-filter>
    <action android:name="android.intent.action.PICK"/>
    <category android:name="android.intent.category.DEFAULT" />
    <category android:name="com.facebook.orca.category.PLATFORM_THREAD_20150314" />
</intent-filter>

      

        
        
        
      

    

Then I use below code to get metadata from Intent

MessengerThreadParams mThreadParams = MessengerUtils.getMessengerThreadParamsForIntent(intent);
String metadata = mThreadParams.metadata;

      

        
        
        
      

    

But still I am not getting the metadata back, I have followed it exactly as mentioned in the Messenger documentation.