define RealmHelper#isObjectExists

realm-helpers/src/main/java/chat/rocket/android/realm_helper/RealmHelper.java

@@ -7,6 +7,7 @@ import android.support.v7.widget.RecyclerView;
 import io.realm.Realm;
 import io.realm.RealmConfiguration;
 import io.realm.RealmObject;
+import io.realm.RealmQuery;
 import io.realm.RealmResults;
 import org.json.JSONException;
 
@@ -73,6 +74,19 @@ public class RealmHelper {
     }
   }
 
+  public interface Query<T extends RealmObject> {
+    RealmQuery<T> query(Realm realm);
+  }
+
+  public <T extends RealmObject> boolean isObjectExists(Query<T> query) {
+    try (Realm realm = instance()) {
+      return query.query(realm).count() > 0;
+    } catch (Exception exception) {
+      RCLog.w(exception);
+      return false;
+    }
+  }
+
   private boolean shouldUseSync() {
     // ref: realm-java:realm/realm-library/src/main/java/io/realm/AndroidNotifier.java
     // #isAutoRefreshAvailable()
@@ -140,7 +154,7 @@ public class RealmHelper {
   }
 
   public <T extends RealmObject> RealmObjectObserver<T> createObjectObserver(
-      RealmObjectObserver.Query<T> query) {
+      RealmHelper.Query<T> query) {
     return new RealmObjectObserver<T>(this, query);
   }
 

realm-helpers/src/main/java/chat/rocket/android/realm_helper/RealmObjectObserver.java

@@ -3,17 +3,16 @@ package chat.rocket.android.realm_helper;
 import io.realm.Realm;
 import io.realm.RealmChangeListener;
 import io.realm.RealmObject;
-import io.realm.RealmQuery;
 import io.realm.RealmResults;
 
 public class RealmObjectObserver<T extends RealmObject> extends AbstractRealmResultsObserver<T> {
 
-  private final Query<T> query;
+  private final RealmHelper.Query<T> query;
   private OnUpdateListener<T> onUpdateListener;
   private Impl<T> impl;
   private String previousResultString;
 
-  /*package*/ RealmObjectObserver(RealmHelper helper, Query<T> query) {
+  /*package*/ RealmObjectObserver(RealmHelper helper, RealmHelper.Query<T> query) {
     super(helper);
     this.query = query;
     setImpl(new Impl<T>());
@@ -54,10 +53,6 @@ public class RealmObjectObserver<T extends RealmObject> extends AbstractRealmRes
     super.sub();
   }
 
-  public interface Query<T extends RealmObject> {
-    RealmQuery<T> query(Realm realm);
-  }
-
   public interface OnUpdateListener<T extends RealmObject> {
     void onUpdateObject(T element);
   }