Updated GridView example with copyToRealm method showing how to use with GSON

cmelchior · cmelchior · commit bccdaa485bbb · 2015-01-09T14:42:01.000+01:00
diff --git a/examples/gridViewExample/build.gradle b/examples/gridViewExample/build.gradle
@@ -25,6 +25,6 @@ tasks.preBuild {
 }
 
 dependencies {
-    compile 'com.google.code.gson:gson:2.3'
+    compile 'com.google.code.gson:gson:1.7.1'
     compile files("../../realm/build/libs/realm-${version}.jar")
 }
diff --git a/examples/gridViewExample/src/main/java/io/realm/examples/realmgridview/GridViewExampleActivity.java b/examples/gridViewExample/src/main/java/io/realm/examples/realmgridview/GridViewExampleActivity.java
@@ -22,14 +22,18 @@
 import android.widget.AdapterView;
 import android.widget.GridView;
 
+import com.google.gson.Gson;
 import com.google.gson.JsonArray;
 import com.google.gson.JsonElement;
 import com.google.gson.JsonParser;
+import com.google.gson.reflect.TypeToken;
 
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
 import java.util.List;
 
 import io.realm.Realm;
@@ -84,8 +88,6 @@ protected void onDestroy() {
     }
 
     private List<City> loadCities() {
-        List<City> items = new ArrayList<City>();
-
         // In this case we're loading from local assets.
         // NOTE: could alternatively easily load from network
         InputStream stream = null;
@@ -95,23 +97,20 @@ private List<City> loadCities() {
             return null;
         }
 
-        JsonParser parser = new JsonParser();
-        JsonArray jsonArray = parser.parse(new InputStreamReader(stream)).getAsJsonArray();
+        // GSON can parse the data.
+        // Note there is a bug in GSON 2.3.1 that can cause it to StackOverflow in some cases.
+        // Downgrading to GSON 1.7.1 usually fixes this.
+        // See more here: https://code.google.com/p/google-gson/issues/detail?id=440
+        JsonArray json = new JsonParser().parse(new InputStreamReader(stream)).getAsJsonArray();
+        List<City> cities = new Gson().fromJson(json.toString(), new TypeToken<List<City>>(){}.getType());
 
         // Open a transaction to store items into the realm
+        // Use copyToRealm() to convert the objects into proper RealmObjects managed by Realm.
         realm.beginTransaction();
-        for (JsonElement e : jsonArray) {
-            // Create a realm capable object
-            City realmCity = realm.createObject(City.class);
-            realmCity.setName(e.getAsJsonObject().get("name").getAsString());
-            realmCity.setVotes(e.getAsJsonObject().get("votes").getAsInt());
-            // Minor optimization to keep the new cities in a list
-            // so it doesn't have to be reloaded the first time
-            items.add(realmCity);
-        }
+        Collection<City> realmCities = realm.copyToRealm(cities);
         realm.commitTransaction();
 
-        return items;
+        return new ArrayList<City>(realmCities);
     }
 
     public void updateCities() {

Original file line number	Diff line number	Diff line change
`@@ -25,6 +25,6 @@ tasks.preBuild {`
`25`	`25`	`}`
`26`	`26`
`27`	`27`	`dependencies {`
`28`		`- compile 'com.google.code.gson:gson:2.3'`
	`28`	`+ compile 'com.google.code.gson:gson:1.7.1'`
`29`	`29`	`compile files("../../realm/build/libs/realm-${version}.jar")`
`30`	`30`	`}`