Develop Reference

How to stop Activity attached AlertDialog keep reappearing over Activity after Activity paused and recreated?

I am working on project, which simply validates through username and password.
I made some progress with using DialogFragments and AlertDialog. AlertDialog appears after starting the app over the mainactivity asking for username and password.
I must set the Alertdialog's setCanceledOnTouchOutside(false) and DialogFragment's setCancelable(false) because I don't want the users to dismiss it with pressing android's back button.
The problem is, after dismissing it programatically on successful login, if the activity becomes invisible and visible again , the Alertdialog's OnShowListener called, showing this AlertDialog again.
Can I somehow "detach" this AlertDialog from Activity? This popups also happen after unlocking the screen and getting back to activity which makes it very annoying...
Here is the code of interest:
MainActivity
public class MainActivity extends AppCompatActivity implements NoticeDialogFragment.NoticeDialogListener {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if(GlobalInformations.getInstance().getUsername()==null){
shownoticeDialog();
}
}
public void shownoticeDialog(){
DialogFragment dialogFragment = new NoticeDialogFragment();
dialogFragment.show(getFragmentManager(), "NoticeDialogFragment");
}
#Override
public void onDismiss(DialogFragment dialog) {
//set the username on a TextView instance, etc...
}
NoticeDialogFragment extends DialogFragment
public class NoticeDialogFragment extends DialogFragment {
public interface NoticeDialogListener{
public void onDialogPositiveClick(DialogFragment dialog);
public void onDialogNegativeClick(DialogFragment dialog);
public void onDismiss(DialogFragment dialog);
}
NoticeDialogListener mListener;
static Activity activity = null;
//static String username;
#Override
public void onAttach(Context context) {
super.onAttach(context);
try{
activity = (Activity) context;
mListener = (NoticeDialogListener) activity;
} catch (ClassCastException e){
throw new ClassCastException(activity.toString() + "must implement NoticeDialogListener");
}
}
#Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
LayoutInflater inflater = getActivity().getLayoutInflater();
View view = inflater.inflate(R.layout.dialog_signin, null);
final AutoCompleteTextView actv_username = (AutoCompleteTextView) view.findViewById(R.id.username);
final EditText password = (EditText) view.findViewById(R.id.password);
getavailableusernames(actv_username);
final AlertDialog dialog = new AlertDialog.Builder(new ContextThemeWrapper(getContext(), R.style.AlertDialogCustom))
.setView(view)
.setTitle("Login")
.setPositiveButton("OK", null)
//.setNegativeButton("Cancel", null)
.create();
dialog.setOnShowListener(new DialogInterface.OnShowListener() {
#Override
public void onShow(DialogInterface dialogInterface) {
final Button button =((AlertDialog) dialog).getButton(AlertDialog.BUTTON_POSITIVE);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String passw = password.getText().toString();
String user = actv_username.getText().toString();
try{
if(user.length()<4 || passw.length()<4){
Toast.makeText(getContext(), "Username/password too short", Toast.LENGTH_SHORT).show();
dialog.show();
}
else {
//login to account, if success dismiss.
login(user, passw,dialog);
}
} catch(Exception e){
}
// dialog.dismiss();
}
});
}
});
dialog.setCanceledOnTouchOutside(false);
// set the DialogFragment to make the dialog unable to dismiss with back button
// (because not working if called on the dialog directly)
this.setCancelable(false);
return dialog;
}
public void login(final String username, String password, final AlertDialog dialog){
boolean login_success = false;
//query the credentials
login_success = dosomesqlquery(username, password);
if(login_success){
dialog.dismiss();
}
}
//passing the handling to activity...
#Override
public void onDismiss(DialogInterface dialog) {
mListener.onDismiss(NoticeDialogFragment.this);
}
}
Thank you for your help and patience.

Well this is that kind of situation where I end up heading my desk continously.
The source of the problem was I called dialog.dismiss() which dismisses the dialog, BUT not the dialogfragment itself, so will never, ever dismissed, even if the dialog disappeared from screen. Placing this.dismiss() in NoticeDialogFragment's onDismiss or anywhere else after login succeded will let the application act as it should.
#Override
public void onDismiss(DialogInterface dialog) {
mListener.onDismiss(NoticeDialogFragment.this);
this.dismiss(); //will dismiss the DialogFragment. Yeeey!
}
Thank you for your time and answers as they helped me point out the real problem. I will modify the code based on your suggestions.

An easier way is to use a static variable in your activity using two steps.
Declare a global static boolean
private static boolean session = false;
Check if the boolean has changed and if not, set the boolean to true when the dialog is shown
public void shownoticeDialog(){
if(session)return;
DialogFragment dialogFragment = new NoticeDialogFragment();
dialogFragment.show(getFragmentManager(), "NoticeDialogFragment");
session = true;
}

Set the value when the activity goes background
#Override
protected void onSaveInstanceState(Bundle outState) {
outState.putBoolean("authUser", GlobalInformations.getInstance().getUsername()==null)
}
and read it when it comes back
#Override
protected void onCreate(Bundle savedInstanceState) {
if(savedInstanceState != null && savedInstanceState.containsKey("authUser")) {
boolean authUser = savedInstanceState.getBoolean("authUser", false);
if(authUser) {
//show or don't show dialog
}
}
}

crash after dialog dismiss in android

I have the following crash
java.lang.IllegalArgumentException: View=DecorView#62c59a[] not attached to window manager
at android.view.WindowManagerGlobal.findViewLocked(WindowManagerGlobal.java:473)
at android.view.WindowManagerGlobal.removeView(WindowManagerGlobal.java:382)
at android.view.WindowManagerImpl.removeViewImmediate(WindowManagerImpl.java:128)
at android.app.Dialog.dismissDialog(Dialog.java:727)
at android.app.Dialog.-android_app_Dialog-mthref-0(Dialog.java:167)
at android.app.Dialog$-void__init__android_content_Context_context_int_themeResId_boolean_createContextThemeWrapper_LambdaImpl0.run(Dialog.java)
at android.os.Handler.handleCallback(Handler.java:751)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6688)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1468)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1358)
can anyone please help and tell me what cause this crash and how to solve it ?
EDIT
this is the method that show the dialog
public static void showDialogMessage(Activity activity, String title,
String message, String buttonString, final OnClickListener listener) {
try {
final Dialog dialog = new Dialog(activity);
dialog.getWindow().requestFeature(Window.FEATURE_NO_TITLE);
dialog.setContentView(R.layout.dialog_error_message_layout);
dialog.setCancelable(false);
TextView titleTV = (TextView) dialog.findViewById(R.id.title_textview);
TextView descriptionTV = (TextView) dialog
.findViewById(R.id.description_textview);
Button okButton = (Button) dialog.findViewById(R.id.ok_button);
Button cancelButton = (Button) dialog.findViewById(R.id.cancel_button);
titleTV.setText(title);
descriptionTV.setText(message);
okButton.setText(buttonString);
cancelButton.setVisibility(View.GONE);
okButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
dialog.dismiss();
if (listener != null)
listener.onClick(null);
}
});
dialog.getWindow().setBackgroundDrawableResource(
android.R.color.transparent);
dialog.show();
} catch (BadTokenException exception) {
exception.printStackTrace();
}
}

The error occurs when Activity gets finished before dialog successfully dismisses. So the Dialog's view is not attached to the windowManager.
Add this check before dismissing the Dialog:
if (!activity.this.isFinishing() && dialog != null) {
dialog.dismiss();
}
Alternatively you can dismiss your dialog in onPause() or onDestroy() of the activity.
#Override
public void onPause() {
super.onPause();
if ((dialog != null) && dialog.isShowing())
dialog.dismiss();
dialog = null;
}

Why doesn't progress spinner work after closing alert dialog in android?

My progress bar is just a spinner.
I am showing two options to user and when user clicks an option, I show a dialog, so that user reads and understands it.
This is what I want.
When they click positive, it should show the spinner and keep calling service on background.
When they click negative, it should make the option unchecked.
Here is the code.
This radioGroup.setOnClickListener goes into onCreateView method of a fragment.
public class Choose_CountryFragment extends Fragment {
private RadioGroup radioGroup;
private TextView textView;
private String countryChosen = null;
ConnectionStatus connectionStatus = new ConnectionStatus(getContext());
public Choose_CountryFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
final Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_choose__country, container, false);
radioGroup = (RadioGroup) rootView.findViewById(R.id.country_choice_radio);
radioGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener()
{
public void onCheckedChanged(RadioGroup group, int checkedId) {
switch(checkedId){
case R.id.countryCanada:
// do operations specific to this selection
countryChosen = "Canada";
Intent explicitServiceIntent = new Intent(getActivity(), Service.class);
explicitServiceIntent.putExtra("country", "Canada");
getActivity().startService(explicitServiceIntent);
connectionStatus.showProgress();
break;
case R.id.countryUSA:
countryChosen = "USA";
Dialog dialog = onCreateDialog(savedInstanceState);
dialog.show();
connectionStatus.showProgress();
break;
}
}
});
public Dialog onCreateDialog(final Bundle savedInstanceState) {
// Use the Builder class for convenient dialog construction
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
Toast.makeText(getContext(), "Click Got it", Toast.LENGTH_LONG).show();
builder.setMessage(R.string.SignUpWarningInfo)
.setPositiveButton(R.string.gotIt, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
Intent explicitServiceIntentUSA = new Intent(getActivity(), Service.class);
explicitServiceIntentUSA.putExtra("country", countryChosen );
getActivity().startService(explicitServiceIntentUSA);
}
})
.setNegativeButton(R.string.cancel, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
return;
}
});
// Create the AlertDialog object and return it
return builder.create();
}
}
}
ConnectionStatus.java
public class ConnectionStatus {
private Context _context;
private ProgressDialog progressDialog = null;
public ConnectionStatus(Context context) {
this._context = context;
}
public void showProgress(){
progressDialog = new ProgressDialog(_context);
progressDialog.setCancelable(false);
progressDialog.setIndeterminate(true);
progressDialog.show();
}
}
Error happens when I click USA.
Error I get
java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.res.Resources$Theme android.content.Context.getTheme()' on a null object reference
at android.app.AlertDialog.resolveDialogTheme(AlertDialog.java:154)
at android.app.AlertDialog.<init>(AlertDialog.java:109)
at android.app.ProgressDialog.<init>(ProgressDialog.java:77)
at com.a2.a2.ConnectionStatus.showProgress(ConnectionStatus.java:66)
at com.a2.a2.signUp.Choose_CountryFragment$1.onCheckedChanged(Choose_CountryFragment.java:73)

Your Context returning null
Change code in Choose_CountryFragment
public class Choose_CountryFragment extends Fragment {
...
protected Context mContext;
private ConnectionStatus connectionStatus
...
public Choose_CountryFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
final Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_choose__country, container, false);
...
connectionStatus = new ConnectionStatus(mContext);// initialize ConnectionStatus here
...
}
}
Override onAttach Inside Choose_CountryFragment
#Override
public void onAttach(Context context) {
super.onAttach(context);
mContext = context;
}

In Fragment, you have to use:
ProgressDialog progressDialog = new ProgressDialog(getActivity);
From the documentation, the getActivity() method returns the Activity this Fragment is currently associated with it.
Edit:
In Activity class, you have to use like:
ProgressDialog progressDialog = new ProgressDialog(YourActivityClassName.this);

NullPointerException when using database object [duplicate]

This question already has answers here:
What is a NullPointerException, and how do I fix it?
(12 answers)
Closed 6 years ago.
I'm new to Android, and i've got some issues.
It looks like it's saying DB.EmployeeOperations.open() is having an null object passed to it, but I'm not sure.
Where I missed a step?
Any help is appreciated.
Thanks in advance.
Logcat:
* 06-10 16:10:52.605 17203-17203/com.androidtutorialpoint.employeemanagementsystem E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.androidtutorialpoint.employeemanagementsystem, PID: 17203
java.lang.RuntimeException: Unable to resume activity {com.androidtutorialpoint.employeemanagementsystem/com.androidtutorialpoint.employeemanagementsystem.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.androidtutorialpoint.employeemanagementsystem.DB.EmployeeOperations.open()' on a null object reference
at android.app.ActivityThread.performResumeActivity(ActivityThread.java:3019)
at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:3050)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2425)
at android.app.ActivityThread.access$900(ActivityThread.java:154)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1321)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5294)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:904)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:699)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.androidtutorialpoint.employeemanagementsystem.DB.EmployeeOperations.open()' on a null object reference
at com.androidtutorialpoint.employeemanagementsystem.MainActivity.onResume(MainActivity.java:148)
at android.app.Instrumentation.callActivityOnResume(Instrumentation.java:1257)
at android.app.Activity.performResume(Activity.java:6076)
at android.app.ActivityThread.performResumeActivity(ActivityThread.java:3008)
at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:3050)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2425)
at android.app.ActivityThread.access$900(ActivityThread.java:154)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1321)
Java Code:
public class MainActivity extends AppCompatActivity{
private Button addEmployeeButton;
private Button editEmployeeButton;
private Button deleteEmployeeButton;
private Button viewAllEmployeeButton;
private EmployeeOperations employeeOps;
private static final String EXTRA_EMP_ID = "com.androidtutorialpoint.empId";
private static final String EXTRA_ADD_UPDATE = "com.androidtutorialpoint.add_update";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
addEmployeeButton = (Button) findViewById(R.id.button_add_employee);
editEmployeeButton = (Button) findViewById(R.id.button_edit_employee);
deleteEmployeeButton = (Button) findViewById(R.id.button_delete_employee);
viewAllEmployeeButton = (Button)findViewById(R.id.button_view_employees);
addEmployeeButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent i = new Intent(MainActivity.this,AddUpdateEmployee.class);
i.putExtra(EXTRA_ADD_UPDATE, "Add");
startActivity(i);
}
});
editEmployeeButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
getEmpIdAndUpdateEmp();
}
});
deleteEmployeeButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
getEmpIdAndRemoveEmp();
}
});
viewAllEmployeeButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent i = new Intent(MainActivity.this, ViewAllEmployees.class);
startActivity(i);
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.employee_menu, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.menu_item_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
public void getEmpIdAndUpdateEmp(){
LayoutInflater li = LayoutInflater.from(this);
View getEmpIdView = li.inflate(R.layout.dialog_get_emp_id, null);
AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(this);
// set dialog_get_emp_id.xml to alertdialog builder
alertDialogBuilder.setView(getEmpIdView);
final EditText userInput = (EditText) getEmpIdView.findViewById(R.id.editTextDialogUserInput);
// set dialog message
alertDialogBuilder
.setCancelable(false)
.setPositiveButton("OK",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int id) {
// get user input and set it to result
// edit text
Intent i = new Intent(MainActivity.this,AddUpdateEmployee.class);
i.putExtra(EXTRA_ADD_UPDATE, "Update");
i.putExtra(EXTRA_EMP_ID, Long.parseLong(userInput.getText().toString()));
startActivity(i);
}
}).create()
.show();
}
public void getEmpIdAndRemoveEmp(){
LayoutInflater li = LayoutInflater.from(this);
View getEmpIdView = li.inflate(R.layout.dialog_get_emp_id, null);
AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(this);
// set dialog_get_emp_id.xml to alertdialog builder
alertDialogBuilder.setView(getEmpIdView);
final EditText userInput = (EditText) getEmpIdView.findViewById(R.id.editTextDialogUserInput);
// set dialog message
alertDialogBuilder
.setCancelable(false)
.setPositiveButton("OK",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int id) {
// get user input and set it to result
// edit text
employeeOps = new EmployeeOperations(MainActivity.this);
employeeOps.removeEmployee(employeeOps.getEmployee(Long.parseLong(userInput.getText().toString())));
Toast t = Toast.makeText(MainActivity.this,"Employee removed successfully!",Toast.LENGTH_SHORT);
t.show();
}
}).create()
.show();
}
#Override
protected void onResume() {
super.onResume();
employeeOps.open();
}
#Override
protected void onPause() {
super.onPause();
employeeOps.close();
}
}

The problem is you're calling employeeOps.open() in onResume(), but employeeOps is not instantiated yet, it's value is still null.
Take a look at the Activity lifecycle.
As you can see, when an Activity gets created two methods get called before onResume(): onCreate() and onStart().
If you would like to call the open() method of EmployeeOperations in onResume(), you need to have an instance of it by then.
Call the following in onCreate():
employeeOps = new EmployeeOperations(this);

Your problem is a misunderstanding of the Android lifecycle. Specifically, from that resource,
Once the onCreate() finishes execution, the system calls the onStart() and onResume() methods in quick succession.
What this means for you is that onResume() triggers before you ever set employeeOps to a non-null value. You're only initializing it in response to a button press, but your Activity is only visible for a very short duration before onResume is triggered.

Android DialogFragment not showing when show() called in onCreate of Activity

I have a dialog fragment with a simple indeterminate progress bar in the centre, which i use to show network activity:
public class NativeLoadingDialogFragment extends DialogFragment {
public NativeLoadingDialogFragment() {
// Blank
}
#Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
Dialog dialog = new Dialog(getActivity(), android.R.style.Theme_Dialog);
ProgressBar indeterminateProgressBar = new ProgressBar(getActivity());
indeterminateProgressBar.setIndeterminate(true);
dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
dialog.setCancelable(false);
dialog.setCanceledOnTouchOutside(false);
dialog.setContentView(indeterminateProgressBar);
dialog.getWindow().setBackgroundDrawable(
new ColorDrawable(android.graphics.Color.TRANSPARENT));
return dialog;
}
public boolean isShowing() {
return getDialog() != null;
}
}
I have used the dialog fragment throughout my app with no issues, it shows up without issue in lots of places when i call dialog.show(getFragmentManager, null), however when I try to call it in onResume of my settings activity it does not show!
I have an activity for settings, which launches the system settings to change the language of the phone. Once the user changes the language and my activity resumes I detect if the language has changed and do a network call:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
mLoading = new NativeLoadingDialogFragment();
if (savedInstanceState != null) {
if (savedInstanceState.containsKey(EXTRA_LANGUAGE)) {
String language = savedInstanceState.getString(EXTRA_LANGUAGE);
String currentLanguage = AppUtils.getDefaultLanguageCode(
SmartBankConstant.DEFAULT_LANGUAGE,
SmartBankConstant.SUPPORTED_LANGUAGES);
if (!language.equals(currentLanguage)) {
updateLanguage(Language.stringToLanguage(currentLanguage));
}
}
}
}
private void updateLanguage(Language newLanguage) {
....
getSpiceManager().execute(new SetLanguageRequest(newLanguage),
new SetLanguageRequestListener(this));
mLoading.show(getFragmentManager(), null);
getFragmentManager().executePendingTransactions();
}
The code definitely runs but no dialog appears! If the network call fails I have a retry option that calls the updateLanguage(Language newLanguage) method again, and the dialog actually appears that time! What am I doing wrong?

Try with this approach. It checks if the dialog is already displayed, otherwise it shows it.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
mLoading = new NativeLoadingDialogFragment();
if (savedInstanceState != null) {
...
}
mLoading.show(getFragmentManager(), null);
}
private void updateLanguage(Language newLanguage) {
...
if (mLoading != null && !mLoading.isVisible()) {
mLoading.show(getFragmentManager(), null);
getFragmentManager().executePendingTransactions();
}
}

I don't know why, but running fragment transaction in the next loop helped to solve this issue.
new Handler().post(new Runnable() {
#Override public void run() {
// for some reason this must be called in the next loop
dialogFragment.show(getSupportFragmentManager(), tag);
}
});