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Why is this code being executed when the user have not selected anything? [duplicate]

I created an Android application with a Spinner and a TextView. I want to display the selected item from the Spinner's drop down list in the TextView. I implemented the Spinner in the onCreate method so when I'm running the program, it shows a value in the TextView (before selecting an item from the drop down list).
I want to show the value in the TextView only after selecting an item from the drop down list. How do I do this?
Here is my code:
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.TextView;
public class GPACal01Activity extends Activity implements OnItemSelectedListener {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Spinner spinner = (Spinner) findViewById(R.id.noOfSubjects);
// Create an ArrayAdapter using the string array and a default spinner layout
ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,R.array.noofsubjects_array, android.R.layout.simple_spinner_item);
// Specify the layout to use when the list of choices appears
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// Apply the adapter to the spinner
spinner.setAdapter(adapter);
spinner.setOnItemSelectedListener(this);
}
public void onItemSelected(AdapterView<?> parent, View arg1, int pos,long id) {
TextView textView = (TextView) findViewById(R.id.textView1);
String str = (String) parent.getItemAtPosition(pos);
textView.setText(str);
}
public void onNothingSelected(AdapterView<?> arg0) {
// TODO Auto-generated method stub
}
}

spinner.setOnItemSelectedListener(this); // Will call onItemSelected() Listener.
So first time handle this with any Integer value
Example:
Initially Take int check = 0;
public void onItemSelected(AdapterView<?> parent, View arg1, int pos,long id) {
if(++check > 1) {
TextView textView = (TextView) findViewById(R.id.textView1);
String str = (String) parent.getItemAtPosition(pos);
textView.setText(str);
}
}
You can do it with boolean value and also by checking current and previous positions. See here

Just put this line before setting the OnItemSelectedListener
spinner.setSelection(0,false)
This works because setSelection(int, boolean) calls setSelectionInt() internally so that when the listener is added, the item is already selected.
Beware that setSelection(int) won't work, because it calls setNextSelectedPositionInt() internally.

Beginning with API level 3 you can use onUserInteraction() on an Activity with a boolean to determine if the user is interacting with the device.
http://developer.android.com/reference/android/app/Activity.html#onUserInteraction()
#Override
public void onUserInteraction() {
super.onUserInteraction();
userIsInteracting = true;
}
As a field on the Activity I have:
private boolean userIsInteracting;
Finally, my spinner:
mSpinnerView.setOnItemSelectedListener(new OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> arg0, View view, int position, long arg3) {
spinnerAdapter.setmPreviousSelectedIndex(position);
if (userIsInteracting) {
updateGUI();
}
}
#Override
public void onNothingSelected(AdapterView<?> arg0) {
}
});
As you come and go through the activity the boolean is reset to false. Works like a charm.

This worked for me
Spinner's initialization in Android is problematic sometimes
the above problem was solved by this pattern.
Spinner.setAdapter();
Spinner.setSelected(false); // must
Spinner.setSelection(0,true); //must
Spinner.setonItemSelectedListener(this);
Setting adapter should be first part and onItemSelectedListener(this) will be last when initializing a spinner. By the pattern above my OnItemSelected() is not called during initialization of spinner

haha...I have the same question.
When initViews() just do like this.The sequence is the key, listener is the last. Good Luck !
spinner.setAdapter(adapter);
spinner.setSelection(position);
spinner.setOnItemSelectedListener(listener);

To avoid calling spinner.setOnItemSelectedListener() during initialization
spinner.setSelection(Adapter.NO_SELECTION, true); //Add this line before setting listener
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
}
#Override
public void onNothingSelected(AdapterView<?> parent) {
}
});

My solution:
protected boolean inhibit_spinner = true;
#Override
public void onItemSelected(AdapterView<?> arg0, View arg1,
int pos, long arg3) {
if (inhibit_spinner) {
inhibit_spinner = false;
}else {
if (getDataTask != null) getDataTask.cancel(true);
updateData();
}
}

You can do this by this way:
AdapterView.OnItemSelectedListener listener = new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
//set the text of TextView
}
#Override
public void onNothingSelected(AdapterView<?> adapterView) {
}
});
yourSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
yourSpinner.setOnItemSelectedListener(listener);
}
#Override
public void onNothingSelected(AdapterView<?> adapterView) {
}
});
At first I create a listener and attributed to a variable callback; then i create a second listener anonymous and when this is called at a first time, this change the listener
=]

The user interaction flag can then be set to true in the onTouch method and reset in onItemSelected() once the selection change has been handled. I prefer this solution because the user interaction flag is handled exclusively for the spinner, and not for other views in the activity that may affect the desired behavior.
In code:
Create your listener for the spinner:
public class SpinnerInteractionListener implements AdapterView.OnItemSelectedListener, View.OnTouchListener {
boolean userSelect = false;
#Override
public boolean onTouch(View v, MotionEvent event) {
userSelect = true;
return false;
}
#Override
public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
if (userSelect) {
userSelect = false;
// Your selection handling code here
}
}
}
Add the listener to the spinner as both an OnItemSelectedListener and an OnTouchListener:
SpinnerInteractionListener listener = new SpinnerInteractionListener();
mSpinnerView.setOnTouchListener(listener);
mSpinnerView.setOnItemSelectedListener(listener);

create a boolean field
private boolean inispinner;
inside oncreate of the activity
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
if (!inispinner) {
inispinner = true;
return;
}
//do your work here
}
#Override
public void onNothingSelected(AdapterView<?> parent) {
}
});

Similar simple solution that enables multiple spinners is to put the AdapterView in a collection - in the Activities superclass - on first execution of onItemSelected(...) Then check to see if the AdapterView is in the collection before executing it. This enables one set of methods in the superclass and supports multiple AdapterViews and therefor multiple spinners.
Superclass ...
private Collection<AdapterView> AdapterViewCollection = new ArrayList<AdapterView>();
protected boolean firstTimeThrough(AdapterView parent) {
boolean firstTimeThrough = ! AdapterViewCollection.contains(parent);
if (firstTimeThrough) {
AdapterViewCollection.add(parent);
}
return firstTimeThrough;
}
Subclass ...
public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
if (! firstTimeThrough(parent)) {
String value = safeString(parent.getItemAtPosition(pos).toString());
String extraMessage = EXTRA_MESSAGE;
Intent sharedPreferencesDisplayIntent = new Intent(SharedPreferencesSelectionActivity.this,SharedPreferencesDisplayActivity.class);
sharedPreferencesDisplayIntent.putExtra(extraMessage,value);
startActivity(sharedPreferencesDisplayIntent);
}
// don't execute the above code if its the first time through
// do to onItemSelected being called during view initialization.
}

Try this
spinner.postDelayed(new Runnable() {
#Override
public void run() {
addListeners();
}
}, 1000);.o

Code
spinner.setOnTouchListener(new View.OnTouchListener() {
#Override public boolean onTouch(View view, MotionEvent motionEvent) { isSpinnerTouch=true; return false; }});
holder.spinner_from.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> adapterView, View view, int slot_position, long l) {
if(isSpinnerTouch)
{
Log.d("spinner_from", "spinner_from");
spinnerItemClickListener.onSpinnerItemClickListener(position, slot_position, AppConstant.FROM_SLOT_ONCLICK_CODE);
}
else {
}
}
#Override
public void onNothingSelected(AdapterView<?> adapterView) {
}
});

You could achieve it by setOnTouchListener first then setOnItemSelectedListener in onTouch
#Override
public boolean onTouch(final View view, final MotionEvent event) {
view.setOnItemSelectedListener(this)
return false;
}

This worked for me:
spinner.setSelection(0, false);
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
spinner.setOnItemSelectedListener(listener);
}, 500);

Based on Abhi's answer i made this simple listener
class SpinnerListener constructor(private val onItemSelected: (position: Int) -> Unit) : AdapterView.OnItemSelectedListener {
private var selectionCount = 0
override fun onNothingSelected(parent: AdapterView<*>?) {
//no op
}
override fun onItemSelected(parent: AdapterView<*>?, view: View?, position: Int, id: Long) {
if (selectionCount++ > 1) {
onItemSelected(position)
}
}
}

You can create custom OnItemSelectedListener like this. I've taken val check=0 and in onItemSelected() method i did check if its count is 0? If 0 means its called during initialization. So simply ignore it.
I've also called separate abstract method called onUserItemSelected() I'll call this method is check > 0. This works perfectly fine for me.
abstract class MySpinnerItemSelectionListener : AdapterView.OnItemSelectedListener {
abstract fun onUserItemSelected(parent: AdapterView<*>?, view: View?, position: Int, id: Long)
private var check = 0
override fun onItemSelected(
parent: AdapterView<*>?,
view: View,
position: Int,
id: Long
) {
if (++check > 1) {
onUserItemSelected(parent, view, position, id)
}
}
override fun onNothingSelected(parent: AdapterView<*>?) {}
}
And then you can set listener like this.
mySpinner.onItemSelectedListener = object : MySpinnerItemSelectionListener() {
override fun onUserItemSelected(
parent: AdapterView<*>?,
view: View?,
position: Int,
id: Long
) {
//your user selection spinner code goes here
}
}

Had the same problem and this works for me:
I have 2 spinners and I update them during init and during interactions with other controls or after getting data from the server.
Here is my template:
public class MyClass extends <Activity/Fragment/Whatever> implements Spinner.OnItemSelectedListener {
private void removeSpinnersListeners() {
spn1.setOnItemSelectedListener(null);
spn2.setOnItemSelectedListener(null);
}
private void setSpinnersListeners() {
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
spn1.setOnItemSelectedListener(MyClass.this);
spn2.setOnItemSelectedListener(MyClass.this);
}
}, 1);
}
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
// Your code here
}
#Override
public void onNothingSelected(AdapterView<?> parent) {
}
}
When the class is initiating use setSpinnersListeners() instead of directly setting the listener.
The Runnable will prevent the spinner from firing onItemSelected right after the you set their values.
If you need to update the spinner (after a server call etc.) use removeSpinnersListeners() right before your update lines, and setSpinnersListeners() right after the update lines. This will prevent onItemSelected from firing after the update.

For me, Abhi's solution works great up to Api level 27.
But it seems that from Api level 28 and upwards, onItemSelected() is not called when listener is set, which means onItemSelected() is never called.
Therefore, I added a short if-statement to check Api level:
public void onItemSelected(AdapterView<?> parent, View arg1, int pos,long id) {
if(Build.VERSION.SDK_INT >= 28){ //onItemSelected() doesn't seem to be called when listener is set on Api 28+
check = 1;
}
if(++check > 1) {
//Do your action here
}
}
I think that's quite weird and I'm not sure wether others also have this problem, but in my case it worked well.

I placed a TextView on top of the Spinner, same size and background as the Spinner, so that I would have more control over what it looked like before the user clicks on it. With the TextView there, I could also use the TextView to flag when the user has started interacting.
My Kotlin code looks something like this:
private var mySpinnerHasBeenTapped = false
private fun initializeMySpinner() {
my_hint_text_view.setOnClickListener {
mySpinnerHasBeenTapped = true //turn flag to true
my_spinner.performClick() //call spinner click
}
//Basic spinner setup stuff
val myList = listOf("Leonardo", "Michelangelo", "Rafael", "Donatello")
val dataAdapter: ArrayAdapter<String> = ArrayAdapter<String>(this, android.R.layout.simple_spinner_dropdown_item, myList)
my_spinner.adapter = dataAdapter
my_spinner.onItemSelectedListener = object : OnItemSelectedListener {
override fun onItemSelected(parent: AdapterView<*>?, view: View, position: Int, id: Long) {
if (mySpinnerHasBeenTapped) { //code below will only run after the user has clicked
my_hint_text_view.visibility = View.GONE //once an item has been selected, hide the textView
//Perform action here
}
}
override fun onNothingSelected(parent: AdapterView<*>?) {
//Do nothing
}
}
}
Layout file looks something like this, with the important part being that the Spinner and TextView share the same width, height, and margins:
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<Spinner
android:id="#+id/my_spinner"
android:layout_width="match_parent"
android:layout_height="35dp"
android:layout_marginStart="10dp"
android:layout_marginEnd="10dp"
android:background="#drawable/bg_for_spinners"
android:paddingStart="8dp"
android:paddingEnd="30dp"
android:singleLine="true" />
<TextView
android:id="#+id/my_hint_text_view"
android:layout_width="match_parent"
android:layout_height="35dp"
android:layout_marginStart="10dp"
android:layout_marginEnd="10dp"
android:background="#drawable/bg_for_spinners"
android:paddingStart="8dp"
android:paddingEnd="30dp"
android:singleLine="true"
android:gravity="center_vertical"
android:text="*Select A Turtle"
android:textColor="#color/green_ooze"
android:textSize="16sp" />
</FrameLayout>
I'm sure the other solutions work where you ignore the first onItemSelected call, but I really don't like the idea of assuming it will always be called.

I solved this problem like this:
In the activity lifecycle method whose name is onResume():
I added Spinner.setOnItemSelectedListener(this);
As a result, when our spinner call onclick method in the initialize, it does not work.
onResume method starts working when the finished Android page is displayed.

Android Spinner load with empty value (popup is shown before populating data)

I am using https://github.com/Chivorns/SmartMaterialSpinner Library for spinner.
When i first click the spinner no adapter is attached to it or spinner items shows empty list..
like
but when i close it and again select it.. data are shown so I believe that .. due to time consuming data fetching .. spinner show empty dialog.. Now I need to handle that.. How can i only show spinner when data is populated or available.. I have tried async task and handler but not get working.. any hint would be appreciated.. Thank you
Edited ...
I have call api on spinner onTouch event to populate data
{
private void ProvinceSpinnerCode(boolean IsEditCase) {
if (IsEditCase) {
//edit case condition
} else {
provinceSpinner.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
mService = RetrofitManager.getApiClient().create(RetrofitInstance.class);
Call<List<SelectModel>> provinceCall = mService.GetProvinces();
provinceCall.enqueue(new Callback<List<SelectModel>>() {
#Override
public void onResponse(Call<List<SelectModel>> call, Response<List<SelectModel>> response) {
if (response.body().size() >= 0) {
provinceSpinner.setAdapter(new SpinnerAdapter(response.body(),AddCustomerActivity.this));
}
}
#Override
public void onFailure(Call<List<SelectModel>> call, Throwable t) {
}
});
return false;
}
});
}
provinceSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
Toast.makeText(AddCustomerActivity.this, "Id is : " + id, Toast.LENGTH_SHORT).show();
provinceId = (int) id;
}
#Override
public void onNothingSelected(AdapterView<?> arg0) {
}
});
}

You are making an API call inside on touch event which will be fired when you will touch the spinner so to solve the problem just do Api call out side that event (may be inside Oncreate).
Right now provinceSpinner has a touch listerner so when you are touching it to open for the first time it is Fetching data so when you are clicking it again the alert is showing data (the data you fetched when you clicked first time)

Android Firebase RecyclerView Adapter Remove Views

I am facing a Firebase RecyclerView problem where I cannot remove unwanted CardViews from my RecyclerViews. In my code I check the city's name and the guide's chosen city to match them. It populates guide's details only if the guide's city matches the picked city, but it also shows empty cardview with default layout.
guideDataRef = FirebaseDatabase.getInstance().getReference().child("Guides");
public void recycler() {
super.onStart();
try {
//Guide RecyclerView
Query guideQuery = guideDataRef.orderByKey();
guideQuery.keepSynced(true);
FirebaseRecyclerOptions guideOptions =
new FirebaseRecyclerOptions.Builder<UserModelClass>().setQuery(guideQuery, UserModelClass.class).build();
guideAdapter = new FirebaseRecyclerAdapter<UserModelClass, guideViewHolder>(guideOptions) {
#Override
protected void onBindViewHolder(#NonNull guideViewHolder holder, final int position, #NonNull final UserModelClass model) {
String pickedcity = model.getPickedCity();
String postname = (String) cityName.getText();
if(pickedcity.equals(postname)) {
final String guide_key= getRef(position).getKey();
holder.setGuideName(model.getName());
holder.setGuideSurname(model.getSurName());
holder.setGuideImage(getApplicationContext(), model.getPhotoURL());
// holder.mView.setVisibility(View.VISIBLE);
//Guide Click listener
holder.mView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent guideHireIntent = new Intent(getApplication(), GuideHireActivity.class);
guideHireIntent.putExtra("guide_id", guide_key);
finish();
startActivity(guideHireIntent);
}
});
}
}
#NonNull
#Override
public guideViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_layout_guides, parent, false);
return new guideViewHolder(view);
}
#Override
public void onError(DatabaseError e){
Toast.makeText(getApplicationContext(), "Error by stopping ", Toast.LENGTH_SHORT).show();
}
#Override
public int getItemCount() {
return super.getItemCount();
}
#Override
public void onDataChanged() {
super.onDataChanged();
notifyDataSetChanged();
}
};
guideAdapter.notifyDataSetChanged();
guideRecyclerView.setAdapter(guideAdapter);
guideAdapter.startListening();
} catch (DatabaseException e) {
Toast.makeText(this, "Error", Toast.LENGTH_SHORT).show();
}
}
enter image description here
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I can change the adapter visibility to gone if it does not match with the requirements but the problem is that after making it's visibility gone it is still there holding the place (but invisible - there's still an empty space). How can I avoid populating an item from the recycler view completely, instead of making it invisible if the requirements do not match?

You're not showing what guideDataRef is in your code, so I'm assuming that it's just aDatabaseReference object for everything beneath a \Guides node.
If you're doing that, you're going to get a call for onBindViewHolder for every child at that particular location. This means that you're going to be asked to make a view for every child. You cannot choose whether or not a view will appear for that item.
It looks like you're assuming that your if statement in onBindViewHolder method will skip over those items. But what's actually happening is that you're simply allowing an empty view to occupy that spot in the list.
Instead, you should come up with a query that generates only the items of interest to your list. This means you'll have to tell Firebase to filter for children that meet your criteria.
You can also read the entire contents of the location, manually filter out the items you don't want, and build a list of items you do want. You can then build an custom adapter with that list, and it can then become the input to a ListView or even better to a RecyclerView.

Set EditText visibility based on Spinner value

I'm trying to create this dialog:
.
When Spinner is set to custom value, TextEdit should automatically appear. I'm calling View.setVisible() on the TextView but the visibility is not evaluated immediately but waits to another change - e.g. adding another row or setting a date.
The code:
...
customText = (EditText) v.findViewById(R.id.edit_custom_text);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
s.setAdapter(adapter);
s.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
SpinnerItem si = (SpinnerItem) adapterView.getItemAtPosition(i);
evt.type = si.eventType;
if (evt.type == EventType.CUSTOM) {
customText.setVisibility(View.VISIBLE);
} else {
customText.setVisibility(View.GONE);
}
}
#Override
public void onNothingSelected(AdapterView<?> adapterView) {
//do nothing
}
});
I tried View.invalidate() (on parent view) and View.refreshDrawableState() with no luck :/
Edit: The code above is reached (verified by debugger) and I also tried View.INVISIBLE. The view is just not refreshed immediately but only after another change in view.

For Example see this
s.setOnItemSelectedListener(new OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parentView,View selectedItemView, int position, long id) {
if ("YES".equals(s.getSelectedItem().toString().toUpperCase())) {
youredittxt.setVisibility(View.VISIBLE);
} else if ("NO".equals(s.getSelectedItem().toString().toUpperCase())) {
youredittxt.setVisibility(View.INVISIBLE);
}}
#Override
public void onNothingSelected(AdapterView<?> arg0) {
// TODO Auto-generated method stub
}
});

That should work, could it be that your layout somehow doesn't allow/recognises this change perhaps?
Try changing it to INVISIBLE instead of GONE, including (important!) in your layout xml file.
If that works for some reason, try something like this:
customText.getParent().requestLayout(); //possibly the parent of that etc

As a follow up question, are you in the main UI thread? Because Android have some built in features and policies, so only the owning thread will be able to change the UI.
If you are outside the same thread, try:
customText.getHandler().post(new Runnable() {
public void run() {
customText.setVisibility(View.VISIBLE);
}
});
Hope this helps! :)

Verify that you are actually reaching your code block.
customText.setVisibility(View.GONE);

User Input causes form to appear

I want to have EditText object appear when a the User chooses "Combination" on a Spinner, How would I do this?
Here is what I have been trying:
ground = (Spinner) findViewById(R.id.ground);
ArrayAdapter<CharSequence> groundAdapter = ArrayAdapter.createFromResource(
this, R.array.ground_array, android.R.layout.simple_spinner_item);
groundAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
ground.setAdapter(groundAdapter);
ground.setOnItemSelectedListener(new GroundListener());
if(ground.getSelectedItem().toString().equalsIgnoreCase("Combination"))
{
combo.setVisibility(0);
}
the EditText object combo is set in xml file as android:visibility="gone"
GroundListener Code is
public class GroundListener implements OnItemSelectedListener {
public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
String selected = parent.getItemAtPosition(pos).toString();
}
public void onNothingSelected(AdapterView parent)
{
// Do nothing.
}
}

What is a GroundListener ?
Shouldn't you be using an AdapterView.OnItemSelectedListener with its onItemSelected method ?
Beside, use setVisibility(View.VISIBLE) instead of 0 for readability.
EDIT:
I don't understand what you are doing with your code, your GroundListener is not plugged to anything and your test is outside of the listener.
Try :
ground.setOnItemSelectedListener(new OnItemSelectedListener() {
public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
if(parent.getItemAtPosition(pos).toString().equalsIgnoreCase("Combination"))
{
combo.setVisibility(View.VISIBLE);
}
}
public void onNothingSelected(AdapterView parent)
{
// Do nothing.
}
});
Check if that works and then bring back the code in your GroundListener to see if it works. You might have a problem though with the fact that the GroundListener might not know what is combo. But you'll work that out.
Edit:
Syntax Correction