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copied!<p>I've found, that if your instance <strong>t</strong> extends from any <strong>android</strong> view component(such as Button, for example) or has field of class, that extends from any <strong>android</strong> view component, you will get such exception</p> <p>For some reason, this library can't serialize <strong>view</strong> components any more. So, you can add exclude strategy. For example, this strategy will exclude all fields, except fields with Annotation @SerializedName:</p> <pre><code>class Exclude implements ExclusionStrategy { @Override public boolean shouldSkipClass(Class<?> arg0) { // TODO Auto-generated method stub return false; } @Override public boolean shouldSkipField(FieldAttributes field) { SerializedName sn = field.getAnnotation(SerializedName.class); if(sn != null) return false; return true; }} </code></pre> <p>Suppose we have sample Json:</p> <pre><code>private final String jsonSample= "{ \"Sample\": { \"field1\":1, \"field2\":2}}"; </code></pre> <p>here is sample code:</p> <pre><code> private void parseJson(){ Exclude ex = new Exclude(); Gson gson = new GsonBuilder().create(); GsonObject gObject = gson.fromJson(jsonSample, GsonObject.class); } class GsonObject{ @SerializedName("Sample") public Smpl smpl; // private Button btn; <-- Uncomment this line, and you will get your error! class Smpl{ @SerializedName("field1") int fl1; @SerializedName("field2") int fl2; } } </code></pre> <p>But after adding <strong>exclude strategy</strong> I've written above:</p> <pre><code> Exclude ex = new Exclude(); Gson gson = new GsonBuilder().addDeserializationExclusionStrategy(ex).addSerializationExclusionStrategy(ex).create(); </code></pre> <p>All works correct.</p> <p>Finally we has the following test app:</p> <pre><code>public class MainActivity extends Activity { private final String jsonSample= "{ \"Sample\": { \"field1\":1, \"field2\":2}}"; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); parseJson(); } private void parseJson(){ Exclude ex = new Exclude(); // Gson gson = new GsonBuilder().create(); <-- without EX strategy it will try to serrialaze Button field in our GsonObject, and throws an exeption Gson gson = new GsonBuilder().addDeserializationExclusionStrategy(ex).addSerializationExclusionStrategy(ex).create(); GsonObject gObject = gson.fromJson(jsonSample, GsonObject.class); Toast.makeText(this, "Gson" + gObject.smpl.fl1 + " " + gObject.smpl.fl2, Toast.LENGTH_LONG).show(); } class GsonObject{ @SerializedName("Sample") public Smpl smpl; private Button btn; // <-- this field is our reason of this strange exception on Gson serialization class Smpl{ @SerializedName("field1") int fl1; @SerializedName("field2") int fl2; } } } class Exclude implements ExclusionStrategy { @Override public boolean shouldSkipClass(Class<?> arg0) { // TODO Auto-generated method stub return false; } @Override public boolean shouldSkipField(FieldAttributes field) { SerializedName ns = field.getAnnotation(SerializedName.class); if(ns != null) return false; return true; } } </code></pre> <p>p.s. Sorry for my English)</p>

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