java.lang.IllegalArgumentException: Pas de parent trouvés à partir de la vue donnée. Veuillez fournir une preuve de la vue

mon application se bloque lorsque vous tentez d'afficher de message serveur et je pense que le problème pourrait être avec mon getView(). ci-dessous est la registerActivity ont été l'incident se produit et mon activity_register.xml

import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.Snackbar;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ProgressBar;
import android.widget.Toast;
import com.fastchat.helper.SQLiteHandler;
import com.fastchat.helper.SessionManager;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;
public class RegisterActivity extends Activity {
private static final String TAG = RegisterActivity.class.getSimpleName();
private Button btnRegister;
private Button btnLinkToLogin;
private EditText inputFullName;
private EditText inputEmail;
private EditText inputPassword;
private ProgressDialog pDialog;
private SessionManager session;
private SQLiteHandler db;
private ProgressBar progress;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
inputFullName = (EditText) findViewById(R.id.name);
inputEmail = (EditText) findViewById(R.id.email);
inputPassword = (EditText) findViewById(R.id.password);
btnRegister = (Button) findViewById(R.id.btnRegister);
btnLinkToLogin = (Button) findViewById(R.id.btnLinkToLoginScreen);
//Progress dialog
pDialog = new ProgressDialog(this);
pDialog.setCancelable(true);
/*
//Session manager
session = new SessionManager(getApplicationContext());
//SQLite database handler
db = new SQLiteHandler(getApplicationContext());
//Check if user is already logged in or not
if (session.isLoggedIn()) {
//User is already logged in. Take him to main activity
Intent intent = new Intent(RegisterActivity.this,
SearchableActivity.class);
startActivity(intent);
finish();
}
*/
//Register Button Click event
btnRegister.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
String name = inputFullName.getText().toString();
String email = inputEmail.getText().toString();
String password = inputPassword.getText().toString();
if (!name.isEmpty() && !email.isEmpty() && !password.isEmpty()) {
registerProcess(name, email, password);
} else {
Toast.makeText(getApplicationContext(),
"Please enter your details!", Toast.LENGTH_LONG)
.show();
}
}
});
//Link to Login Screen
btnLinkToLogin.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
Intent i = new Intent(getApplicationContext(),
LoginActivity.class);
startActivity(i);
finish();
}
});
}   
private void registerProcess(String name,String email,String password){
String tag_string_req = "req_register";
//pDialog = new AlertDialog.Builder(getActivity());
pDialog.setMessage("please wait");
pDialog.show();
Retrofit retrofit = new Retrofit.Builder()
.baseUrl(Constants.BASE_URL)
.addConverterFactory(GsonConverterFactory.create())
.build();
RequestInterface requestInterface = retrofit.create(RequestInterface.class);
User user = new User();
user.setName(name);
user.setEmail(email);
user.setPassword(password);
ServerRequest request = new ServerRequest();
request.setOperation(Constants.REGISTER_OPERATION);
request.setUser(user);
Call<ServerResponse> response = requestInterface.operation(request);
response.enqueue(new Callback<ServerResponse>() {
private View view;
public View getView() {
return view;
}
@Override
public void onResponse(Call<ServerResponse> call, retrofit2.Response<ServerResponse> response) {
ServerResponse resp = response.body();
if(resp !=null)//tried to check if resp is null but its not
//crash occurs here
Snackbar.make(getView(),resp.getMessage(), Snackbar.LENGTH_LONG).show();
pDialog.dismiss();
}
@Override
public void onFailure(Call<ServerResponse> call, Throwable t) {
//progress.setVisibility(View.INVISIBLE);
Log.d(Constants.TAG, "failed");
Toast.makeText(getApplicationContext(), t.getLocalizedMessage(), Toast.LENGTH_LONG).show();
pDialog.dismiss();
}
});
}

activity_register.xml

  <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
xmlns:tools="http://schemas.android.com/tools"
android:background="@color/bg_register"
android:gravity="center"
android:orientation="vertical"
android:padding="10dp"
android:id="@+id/chat">
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:orientation="vertical"
android:paddingLeft="20dp"
android:paddingRight="20dp" >
<ImageView
android:layout_width="389dp"
android:layout_height="72dp"
android:layout_gravity="center_horizontal"
android:layout_marginBottom="24dp"
android:src="@drawable/logo"
tools:ignore="ContentDescription" />
<EditText
android:id="@+id/name"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="10dp"
android:background="@color/input_register_bg"
android:hint="@string/hint_name"
android:padding="10dp"
android:singleLine="true"
android:inputType="textCapWords"
android:textColor="@color/input_register"
android:textColorHint="@color/input_register_hint" />
<EditText
android:id="@+id/email"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="10dp"
android:background="@color/input_register_bg"
android:hint="@string/hint_email"
android:inputType="textEmailAddress"
android:padding="10dp"
android:singleLine="true"
android:textColor="@color/input_register"
android:textColorHint="@color/input_register_hint" />
<EditText
android:id="@+id/password"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="10dp"
android:background="@color/input_register_bg"
android:hint="@string/hint_password"
android:inputType="textPassword"
android:padding="10dp"
android:singleLine="true"
android:textColor="@color/input_register"
android:textColorHint="@color/input_register_hint" />
<!-- Login Button -->
<Button
android:id="@+id/btnRegister"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginTop="20dip"
android:background="#ea4c88"
android:text="register"
android:textColor="@color/white" />
<!-- Link to Login Screen -->
<Button
android:id="@+id/btnLinkToLoginScreen"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginTop="40dip"
android:background="@null"
android:text="already a member? login"
android:textAllCaps="false"
android:textColor="@color/white"
android:textSize="15dp" />
</LinearLayout>

ci-dessous est logcat message

 java.lang.IllegalArgumentException: No suitable parent found from the given view. Please provide a valid view.
at android.support.design.widget.Snackbar.make(Snackbar.java:137)
at com.chat.RegisterActivity$3.onResponse(RegisterActivity.java:143)
at retrofit2.ExecutorCallAdapterFactory$ExecutorCallbackCall$1$1.run(ExecutorCallAdapterFactory.java:68)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)