I do not why my private variable values are getting to null after the Volley request
When i am printing the values in onResponse, i am getting required values, but after volley request is completed, I am getting null.
ListView userListView;
StringRequest stringRequest=null;
ProgressDialog progressDialog;
private String[] strUsername;
private String[] strUserItems;
private String[] strUserImagePaths;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_user_listing);
userListView=findViewById(R.id.userListView);
progressDialog=new ProgressDialog(this);
StrictMode.setThreadPolicy((new StrictMode.ThreadPolicy.Builder().permitNetwork().build()));
displayUserListing();
UserListCustomViewAdapter viewAdapter=new UserListCustomViewAdapter(this,strUsername,strUserImagePaths,strUserItems);
userListView.setAdapter(viewAdapter);
}
private void displayUserListing()
{
progressDialog.setMessage("Getting User List...");
progressDialog.show();
stringRequest=new StringRequest(
Request.Method.GET, Constants.URL_GetUserList, new Response.Listener<String>()
{
#Override
public void onResponse(String response)
{
progressDialog.dismiss();
try {
Log.d("first","before");
JSONArray jsonObj=new JSONArray(response);
strUsername=new String[jsonObj.length()];
strUserItems=new String[jsonObj.length()];
strUserImagePaths=new String[jsonObj.length()];
String str=null;
for(int i=0;i<jsonObj.length();i++)
{
JSONObject jsonObject=jsonObj.getJSONObject(i);
strUsername[i]=jsonObject.getString("user_name");
strUserItems[i]=jsonObject.getString("user_item");
strUserImagePaths[i]=jsonObject.getString("user_image_path");
str+=strUsername[i];
}
Log.d("first","after"+str);
}catch (Exception e)
{
e.printStackTrace();
}
}
}, new Response.ErrorListener()
{
#Override
public void onErrorResponse(VolleyError error)
{
progressDialog.hide();
Log.d("myerror","I got some error");
NetworkResponse networkResponse = error.networkResponse;
Log.d("myerror1",error.getMessage());
// Toast.makeText(getApplicationContext(),error.getMessage().toString(),Toast.LENGTH_LONG).show();
}
})
{
#Override
protected Map<String, String> getParams() throws AuthFailureError
{
Map<String,String> params=new HashMap<String,String>();
params.put("struserid","1");
//params.put("serviceid","1");
return params;
}
};
RequestHandler.getInstance(this).addToRequestQueue(stringRequest);
}
I think you are using your variables before initializing it. Call the adapter after you parsing value.
Related
java.lang.NullPointerException: Parameter specified as non-null is
null: method kotlin.jvm.internal.Intrinsics.checkNotNullParameter,
parameter id
at com.stripe.android.paymentsheet.PaymentSheet$CustomerConfiguration.(PaymentSheet.kt)
at com.abdullahalzazai.welcome2.MainActivity2.paymentFlow(MainActivity2.java:102)
at com.abdullahalzazai.welcome2.MainActivity2.access$000(MainActivity2.java:29)
at com.abdullahalzazai.welcome2.MainActivity2$1.onClick(MainActivity2.java:57)
at android.view.View.performClick(View.java:5637)
public class MainActivity2 extends AppCompatActivity {
Button payment;
String PublishableKey ="pk_test_51MWOxeHw41kgZTMnEfStv1DZsXRvXAQk3RrZrv7tH3U8KHzGhvpNJsyrri7SQpY9nOvyeLIbTfTVa1tK7nh5egfu00A0dBYpw9";
String SecretKey="sk_test_51MWOxeHw41kgZTMnhE1cH6j3eo9SaiSCz1bO2JdI5A0T3392jHFHMhexotB8MslRlHwOGoEDqtsKnY5opU3kLTxB00XBmE2Dox";
String CustomerId;
String EphericalKey;
String ClientSecret;
PaymentSheet paymentSheet;
#SuppressLint("MissingInflatedId")
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
payment= findViewById(R.id.payment);
PaymentConfiguration.init(this,PublishableKey);
paymentSheet = new PaymentSheet(this,paymentSheetResult -> {
onPaymentresult(paymentSheetResult);
});
payment.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
paymentFlow();
}
});
StringRequest request = new StringRequest(Request.Method.POST, "https://api.stripe.com/v1/customers ",
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try {
JSONObject object = new JSONObject(response);
CustomerId = object.getString("id");
Toast.makeText(MainActivity2.this,CustomerId,Toast.LENGTH_SHORT).show();
getEmphericalKey();
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(MainActivity2.this,error.getLocalizedMessage(),Toast.LENGTH_SHORT).show();
}
}){
#Nullable
#Override
protected Map<String, String> getParams() throws AuthFailureError {
Map<String, String> header = new HashMap<>();
header.put("Authorization","Bearer"+SecretKey);
return header;
}
};
RequestQueue requestQueue = Volley.newRequestQueue(this);
requestQueue.add(request);
}
private void paymentFlow() {
paymentSheet.presentWithPaymentIntent(ClientSecret,new PaymentSheet.Configuration("Learn with Arvind",new PaymentSheet.CustomerConfiguration(
CustomerId,
EphericalKey
)));
}
private void onPaymentresult(PaymentSheetResult paymentSheetResult) {
if (paymentSheetResult instanceof PaymentSheetResult.Completed){
Toast.makeText(this,"payment success",Toast.LENGTH_SHORT).show();
}
}
private void getEmphericalKey() {
StringRequest request = new StringRequest(Request.Method.POST, "https://api.stripe.com/v1/ephemeral_keys",
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try {
JSONObject object = new JSONObject(response);
EphericalKey = object.getString("id");
Toast.makeText(MainActivity2.this,CustomerId,Toast.LENGTH_SHORT).show();
getClintSecret(CustomerId,EphericalKey);
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(MainActivity2.this,error.getLocalizedMessage(),Toast.LENGTH_SHORT).show();
}
}){
#Nullable
#Override
protected Map<String, String> getParams() throws AuthFailureError {
Map<String, String> header = new HashMap<>();
header.put("Authorization","Bearer"+SecretKey);
header.put("Stripe-Version","2022-08-01");
return header;
}
#Nullable
#Override
protected Map<String, String> getPostParams() throws AuthFailureError {
Map<String, String> params = new HashMap<>();
params.put("customer",CustomerId);
return params;
}
};
RequestQueue requestQueue = Volley.newRequestQueue(this);
requestQueue.add(request);
}
private void getClintSecret(String customerId, String ephericalKey) {
StringRequest request = new StringRequest(Request.Method.POST, " https://api.stripe.com/v1/payment_intents",
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try {
JSONObject object = new JSONObject(response);
ClientSecret=object.getString("client_secret");
Toast.makeText(MainActivity2.this,ClientSecret,Toast.LENGTH_SHORT).show();
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(MainActivity2.this,error.getLocalizedMessage(),Toast.LENGTH_SHORT).show();
}
}){
#Nullable
#Override
protected Map<String, String> getParams() throws AuthFailureError {
Map<String, String> header = new HashMap<>();
header.put("Authorization","Bearer"+SecretKey);
return header;
}
#Nullable
#Override
protected Map<String, String> getPostParams() throws AuthFailureError {
Map<String, String> params = new HashMap<>();
params.put("customer",CustomerId);
params.put("amount","100"+"00");
params.put("currency_payment_methods[enabled]","true");
return params;
}
};
RequestQueue requestQueue = Volley.newRequestQueue(this);
requestQueue.add(request);
}
}`
I am having a problem where in the Fragment the "getString()" says "Method invocation 'getString' may produce 'NullPointerException'" that's the only problem. The Fragment is stored in MainActivity in Navigation Window.
LoginActivity (Where MainActivity is getting the Data):
private void LoginMethod(String email, String password) {
StringRequest stringRequest = new StringRequest(Request.Method.POST, URL, new Response.Listener() {
#Override
public void onResponse(String response) {
try {
JSONObject jsonObject = new JSONObject(response);
String result = jsonObject.getString("success");
JSONArray jsonArray = jsonObject.getJSONArray("login");
if (result.equals("1")){
for (int i = 0; i < jsonArray.length(); i++){
JSONObject object = jsonArray.getJSONObject(i);
String username = object.getString("Username").trim();
String email = object.getString("Email").trim();
Toast.makeText(Login.this, "Login Success: " + username, Toast.LENGTH_SHORT).show();
Intent intent = new Intent(Login.this, MainActivity.class);
intent.putExtra("username", username);
intent.putExtra("email", email);
startActivity(intent);
}
}
else if (result.equals("0")) {
Toast.makeText(Login.this, "Login Failed" + result + response, Toast.LENGTH_LONG).show(); Log.e("JSON Error", response);
Log.e("Login Error", result);
}
}
catch (JSONException e){
Toast.makeText(Login.this, e.getMessage(), Toast.LENGTH_LONG).show();
Log.e("JSON Error", response);
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(Login.this, error.getMessage(), Toast.LENGTH_SHORT).show();
}
})
{
#Override
protected Map<String, String> getParams() throws AuthFailureError {
Map<String, String> params = new HashMap<>();
params.put("Email", email);
params.put("Password", password);
return params;
}
};
RequestQueue requestQueue = Volley.newRequestQueue(this);
requestQueue.add(stringRequest);
}
**MainActivity:**
public class MainActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener {
Toolbar toolbar;
TextView getemail, getusername;
DrawerLayout drawerLayout;
NavigationView navigationView;
View navheader;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Log.i("State","onCreate");
toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
drawerLayout = findViewById(R.id.drawerLayout);
navigationView = findViewById(R.id.nav_view);
navigationView.setNavigationItemSelectedListener(this);
navheader = navigationView.getHeaderView(0);
String getUsername = getIntent().getStringExtra("username");
String getEmail = getIntent().getStringExtra("email");
getusername = navheader.findViewById(R.id.getusername);
getemail = navheader.findViewById(R.id.getemail);
toolbar.setTitle(getUsername);
getusername.setText(getUsername);
getemail.setText(getEmail);
ActionBarDrawerToggle actionBarDrawerToggle = new ActionBarDrawerToggle(this, drawerLayout, toolbar,
R.string.nav_drawer_open, R.string.nav_drawer_close);
drawerLayout.addDrawerListener(actionBarDrawerToggle);
actionBarDrawerToggle.syncState();
if (savedInstanceState == null){
getSupportFragmentManager().beginTransaction().replace(R.id.fragment_container,
new Home()).commit();
navigationView.setCheckedItem(R.id.home);
}
}
public void getAccountFragmentData(){
String test = "akshdasjkdhsajkdasdas";
String test2 = "wadahawawaawaww";
Bundle bundle = new Bundle();
bundle.putString("username", test);
bundle.putString("email", test2);
Account account = new Account();
account.setArguments(bundle);
Toast.makeText(this, "Account", Toast.LENGTH_SHORT).show();
}
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem item) {
switch (item.getItemId()){
case R.id.home:
getSupportFragmentManager().beginTransaction().replace(R.id.fragment_container,
new Home()).commit();
break;
case R.id.orderfood:
getSupportFragmentManager().beginTransaction().replace(R.id.fragment_container,
new FoodOrder()).commit();
break;
case R.id.account:
getAccountFragmentData();
getSupportFragmentManager().beginTransaction().replace(R.id.fragment_container,
new Account()).commit();
break;
case R.id.settings:
getSupportFragmentManager().beginTransaction().replace(R.id.fragment_container,
new Settings()).commit();
break;
case R.id.email:
Toast.makeText(this, "Email", Toast.LENGTH_SHORT).show();
break;
case R.id.share:
Toast.makeText(this, "Share", Toast.LENGTH_SHORT).show();
break;
}
drawerLayout.closeDrawer(GravityCompat.START);
return true;
}
#Override
public void onBackPressed() {
if (drawerLayout.isDrawerOpen(GravityCompat.START)){
drawerLayout.closeDrawer(GravityCompat.START);
}
else {
super.onBackPressed();
}
}
#Override
protected void onStart() {
super.onStart();
Log.i("State","onStart");
}
#Override
protected void onResume() {
super.onResume();
Log.i("State","onResume");
}
#Override
protected void onPause() {
super.onPause();
Log.i("State","onPause");
}
#Override
protected void onStop() {
super.onStop();
Log.i("State","onStop");
}
#Override
protected void onRestart() {
super.onRestart();
Log.i("State","onRestart");
}
#Override
protected void onDestroy() {
super.onDestroy();
Log.i("State","onDestroy");
}
}
**Fragment:
**
public class Account extends Fragment {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View v = inflater.inflate(R.layout.fragment_account, container, false);
TextView getUsername = v.findViewById(R.id.username);
TextView getEmail = v.findViewById(R.id.email);
Bundle bundle = this.getArguments();
String setUsername = bundle.getString("username");
String setEmail = bundle.getString("email");
getUsername.setText(setUsername);
getEmail.setText(setEmail);
Log.i("Data Sent", "Sent");
return v;
}
I want the Fragment to get the data from MainActivity.
SwipeRefreshLayout refreshLayout = findViewById(R.id.refresh_grid);
refreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
#Override
public void onRefresh() {
getImages();
refreshLayout.setRefreshing(false);
}
});
getImages();
}
I want to know how to randomly display images in gridview through SwipeRefreshLayout
I want a UI like the site https://www.pinterest.com
I want to show random images on refresh to show a lot of images, can you tell me how?
thank you in advance
Below is the full code.
public class MainActivity extends AppCompatActivity {
private List<String> mImagesLinks = new ArrayList<>();
private GridView mGridView;
FloatingActionButton option_01;
FloatingActionButton option_02;
FloatingActionButton option_03;
FloatingActionButton option_04;
static final int PERMISSIONS_REQUEST = 0x0000001;
//종료팝업 전면광고 추가
private static final String TAG = "ted";
TedAdmobDialog nativeTedAdmobDialog;
int nCurrentPermission = 0;
private AdView mAdView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
MobileAds.initialize(this, getString(R.string.admob_app_id));
mAdView = findViewById(R.id.adView);
AdRequest adRequest = new AdRequest.Builder().build();
mAdView.loadAd(adRequest);
checkPermission();
mGridView = findViewById(R.id.grid_view);
mGridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
startActivity(new Intent(MainActivity.this, ImageActivity.class)
.putExtra("Link", mImagesLinks.get(i)));
}
});
option_01 = findViewById(R.id.option_01);
option_01.setOnClickListener(v -> {
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse("https://play.google.com/store/apps/details?id=" + getPackageName()));
startActivity(intent);
});
option_02 = findViewById(R.id.option_02);
option_02.setOnClickListener(v -> {
Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse("https://play.google.com/store/apps/developer?id=Project+J+Lab"));
startActivity(intent);
});
option_03 = findViewById(R.id.option_03);
option_03.setOnClickListener(v -> {
Intent myintent = new Intent(Intent.ACTION_SEND);
myintent.setType("text/plan");
String shereBoday = "Your Boday Here";
String shereSub = "\"http://play.google.com/store/apps/details?id=" + getPackageName();
myintent.putExtra(Intent.EXTRA_SUBJECT, shereBoday);
myintent.putExtra(Intent.EXTRA_TEXT, shereSub);
startActivity(Intent.createChooser(myintent, "shere Using"));
});
option_04 = findViewById(R.id.option_04);
option_04.setOnClickListener(v -> {
Intent email = new Intent(Intent.ACTION_SEND);
email.setType("plain/text");
String[] address = {"dhsthdwjd1#gmail.com"};
email.putExtra(Intent.EXTRA_EMAIL, address);
email.putExtra(Intent.EXTRA_SUBJECT, getPackageName());
email.putExtra(Intent.EXTRA_TEXT, "text");
startActivity(email);
});
SwipeRefreshLayout refreshLayout = findViewById(R.id.refresh_grid);
refreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
#Override
public void onRefresh() {
getImages();
refreshLayout.setRefreshing(false);
}
});
getImages();
}
private void getImages() {
Call<List<String>> imagesResponse = NetworkUtils.getInterface().loadImages();
imagesResponse.enqueue(new Callback<List<String>>() {
#Override
public void onResponse(Call<List<String>> call, Response<List<String>> response) {
if (response.isSuccessful()) {
mImagesLinks = response.body();
ImagesAdapter imagesAdapter = new ImagesAdapter(MainActivity.this, mImagesLinks);
mGridView.setAdapter(imagesAdapter);
imagesAdapter.notifyDataSetChanged();
} else {
Toast.makeText(MainActivity.this, R.string.error_response, Toast.LENGTH_SHORT).show();
}
}
#Override
public void onFailure(Call<List<String>> call, Throwable t) {
Toast.makeText(MainActivity.this, t.getLocalizedMessage(), Toast.LENGTH_LONG).show();
}
});
}
#Override
public void onBackPressed() {
//종료팝업 전면광고 추가
nativeTedAdmobDialog = new TedAdmobDialog.Builder(MainActivity.this, TedAdmobDialog.AdType.NATIVE, getString(R.string.banner_ad_unit_id_native))
.setOnBackPressListener(new OnBackPressListener() {
#Override
public void onReviewClick() {
}
#Override
public void onFinish() {
finish();
}
#Override
public void onAdShow() {
log("onAdShow");
nativeTedAdmobDialog.loadNative();
}
})
.create();
nativeTedAdmobDialog.show();
}
//종료팝업 전면광고 추가
private void log(String text) {
Log.d(TAG, text);
}
private void checkPermission() {
PermissionListener permissionlistener = new PermissionListener() {
#Override
public void onPermissionGranted() {
}
#Override
public void onPermissionDenied(List<String> deniedPermissions) {
}
};
TedPermission.with(this)
.setPermissionListener(permissionlistener)
.setPermissions(
Manifest.permission.INTERNET,
Manifest.permission.ACCESS_NETWORK_STATE,
Manifest.permission.WRITE_EXTERNAL_STORAGE,
Manifest.permission.READ_EXTERNAL_STORAGE,
Manifest.permission.SET_WALLPAPER,
Manifest.permission.READ_CONTACTS)
.check();
}
}
Just use Collections.shuffle(list); in your getImages() function.
Refer this for more information : https://www.geeksforgeeks.org/shuffle-or-randomize-a-list-in-java/
When my app is installed I want to see a progress bar until the image is loaded by an API call. After that, I want to make it invisible.
Here is the code:
public class MainActivity extends AppCompatActivity {
private ImageView imageView;
// ...
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
imageView=findViewById(R.id.imageView);
loud();
}
private void loud(){
setProgressBarVisibility(true);
RequestQueue queue = Volley.newRequestQueue(this);
String url ="https://meme-api.herokuapp.com/gimme";
// Request a string response from the provided URL.
JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(Request.Method.GET, url, null, new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
String url= null;
try {
url = response.getString("url");
} catch (JSONException e) {
e.printStackTrace();
}
setProgressBarVisibility(false);
Glide.with(MainActivity.this).load(url).into(imageView);
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Log.d("ERROR ","Error ");
}
});
queue.add(jsonObjectRequest);
}
how can i solve null object while sending post request
error says
to invoke interface method 'retrofit2.Call com.itgrepnet.foodbundle.remote.UserService.addUser(com.itgrepnet.foodbundle.model.User)' on a null object reference
in AddUserActivity
btnSubmit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
addNewUser();
}
private void addNewUser() {
User u = new User();
u.setFirstname(first_name.getText().toString());
u.setLastname(last_name.getText().toString());
u.setEmail(email.getText().toString());
u.setPassword(password.getText().toString());
Call<User> call = userService.addUser(u);
call.enqueue(new Callback<User>() {
#Override
public void onResponse(Call<User> call, Response<User> response) {
if (response.isSuccessful()) {
Toast.makeText(getApplicationContext(), "User Created Successfully!", Toast.LENGTH_LONG).show();
}
}
#Override
public void onFailure(Call<User> call, Throwable t) {
Log.e("Error: ", t.getMessage());
}
});
}
});
UserService.java
#POST("user/")
Call<User> addUser(#Body User user);
RetrofitClient.java
public class RetrofitClient {
private static Retrofit retrofit = null;
public static Retrofit getClient(String url) {
if (retrofit == null) {
retrofit = new Retrofit.Builder().baseUrl(url)
.addConverterFactory(GsonConverterFactory.create())
.build();
}
return retrofit;
}
}