Develop Reference

spinner setOnItemSelectedListener does not working

anybody can help! the spinner listener doesn't work by this fragment.
it's never called
I have tried to implement an AdapterView.OnItemSelectedListener
I try to implement the spinner in Fragment I don't know if that really matter
Java code
'''
Spinner mSpinner = (Spinner) view.findViewById(R.id.usernameSpinner);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(getActivity(),android.R.layout.simple_spinner_item, users);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
mSpinner.setAdapter(adapter);
mSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
Log.d(TAG, "onItemSelected: " + position);
//its never called
}
#Override
public void onNothingSelected(AdapterView<?> parent) {
}
});
'''

retrieving integer value from spinner

i have two spiners, the first spinner is an Integer array and second is an array of 2D strings.
ArrayAdapter adapter1,adapter3;
String selectedsection;
Integer selectedsem;
Integer[] semester= new Integer[] {1, 2, 3, 4, 5};
String[][] subject=new String[][]{{"m1"},{"m2"},{"m3"},{"m4"},{"m5"},{"m6"},{"m7"},{"m8"}};
adapter1 = new ArrayAdapter<Integer>(this, android.R.layout.simple_spinner_item, semester);
adapter1.setDropDownViewResource(android.R.layout.simple_spinner_item);
sp1.setAdapter(adapter1);
sp1.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
selectedsem = (Integer)parent.getItemAtPosition(position);
Toast.makeText(getApplicationContext(),String.valueOf(selectedsem),Toast.LENGTH_SHORT).show();
}
#Override
public void onNothingSelected(AdapterView<?> parent) {}
});
adapter3 = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, subject[selectedsem]);
adapter3.setDropDownViewResource(android.R.layout.simple_spinner_item);
sp3.setAdapter(adapter3);
sp3.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
selectedsubject = parent.getItemAtPosition(position).toString();
Toast.makeText(getApplicationContext(),String.valueOf(selectedsem),Toast.LENGTH_SHORT).show();
Toast.makeText(getApplicationContext(), selectedsubject, Toast.LENGTH_SHORT).show();
}
#Override
public void onNothingSelected(AdapterView<?> parent) {}
});
the app crashes because it cannot find the value of selectedsem. SO, how to get the value of selectedsem from first spinner use it in second spinner.
Hope the question is understood!

The reason is since it's Integer it can be null and you are trying to use it while initializing it and nothing is yet selected you may get nullpointerexception so better give it a default value of 0 or something at initialization
and then just create adapter for second spinner after the user selects the item.
You can place your second adapter creation just under onItemSelected
sp1.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
selectedsem = semester[parent.getSelectedItemPosition()];
//second adapter code goes here
ArrayAdapter<String> adapterNew = new ArrayAdapter<String>(YourActivity.this, android.R.layout.simple_spinner_item, subject[selectedsem]);
sp3.setAdapter(adapterNew);
Toast.makeText(getApplicationContext(),String.valueOf(selectedsem),Toast.LENGTH_SHORT).show();
}
#Override
public void onNothingSelected(AdapterView<?> parent) {}
});
we are just updating the second spinner just after the user selects some value in(OnItemSelected) the first spinner.

Try to make the second adapter in another function and call it right after the first adapter made, I mean try to schedule the two task not asynchronous not asynchronous

This is happening because the method onItemSelected of your first spinner's OnItemSelectedListener is only called when the spinner actually gets selected by user. So, when you try to instantiate your adapter3, selectedsem is still null. To fix this, you have to put all the code where you expect selectedsem to have a value, right after it actually gets a value, that is: inside onItemSelected method. Like this:
sp1.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
selectedsem = (Integer)parent.getItemAtPosition(position);
Toast.makeText(getApplicationContext(),String.valueOf(selectedsem),Toast.LENGTH_SHORT).show();
if (selectedsem != null) {
adapter3 = new ArrayAdapter<String>(YourActivity.this, android.R.layout.simple_spinner_item, subject[selectedsem]);
adapter3.setDropDownViewResource(android.R.layout.simple_spinner_item);
sp3.setAdapter(adapter3);
sp3.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
selectedsubject = parent.getItemAtPosition(position).toString();
Toast.makeText(getApplicationContext(),String.valueOf(selectedsem),Toast.LENGTH_SHORT).show();
Toast.makeText(getApplicationContext(), selectedsubject, Toast.LENGTH_SHORT).show();
}
#Override
public void onNothingSelected(AdapterView<?> parent) {}
});
}
}
#Override
public void onNothingSelected(AdapterView<?> parent) {}
});
}

Android Adding list item giving Error

I have two lists I am adding the item from the list1, when clicked, to the other list but when I click an item. program is ending with out any errors
debug shows exception error
Following is the code :-
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
String lst1[] = {"abdul","yousuf","khalid","john","egor"};
String lst2[]= {};
Double lp1[]={10.0,5.0,2.0,0.5,1.5};
Double lp12[]={};
ListView lis1= (ListView)findViewById(R.id.lv1);
ListView lis2= (ListView)findViewById(R.id.lv2);
ArrayAdapter<String> adapter1 =new ArrayAdapter<String>(MainActivity.this,android.R.layout.simple_list_item_1,lst1);
final ArrayAdapter<String> adapter2 =new ArrayAdapter<String>(MainActivity.this,android.R.layout.simple_list_item_1,lst2);
lis1.setAdapter(adapter1);
lis2.setAdapter(adapter2);
lis1.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
String item = ((TextView)view).getText().toString();
adapter2.add(item);
}
});
}

Because when you use
ArrayAdapter<String> adapter1 =new ArrayAdapter<String>(MainActivity.this,
android.R.layout.simple_list_item_1,lst2);`
// Internally a fixed size list will be generated ^^^^
then lst2 array will be converted to a fixed length list which cannot accept new entries
public More ...ArrayAdapter(Context context, int resource, int textViewResourceId, T[] objects) {
init(context, resource, textViewResourceId, Arrays.asList(objects));
// fixed length array
}
Read about asList
Solution :
ArrayAdapter<String> adapter1 =new ArrayAdapter<String>(MainActivity.this,
android.R.layout.simple_list_item_1,
new ArrayList<String>(Arrays.asList(lst1));
// Pass array as new mutable list
final ArrayAdapter<String> adapter2 =new ArrayAdapter<String>(MainActivity.this,
android.R.layout.simple_list_item_1,
new ArrayList<String>(Arrays.asList(lst2));

try this
lis1.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
String item =lst1[position];
adapter2.add(item);
}
});

here is solution
lis1.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
String item = ((TextView)view).getText().toString();
lst2.add(item);
adapter2.notifyDataSetChanged();
}
});

Open Text plain when spinner option get selected

i got a spinner with some options, and i want to change visibility of text box when the specific "other" option get selected , how should i do this ?
this.arraySpinner = new String[] {"Mobile", "Gaming", "Media Features", "Medical", "Sports And Nutrition","Security","Space","Other"};
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_spinner_item, arraySpinner);
categories.setAdapter(adapter);

Try this:
.................
........................
this.arraySpinner = new String[] {"Mobile", "Gaming", "Media Features", "Medical", "Sports And Nutrition","Security","Space","Other"};
// Views
categories= (Spinner) findViewById(R.id.spinner);
textView = (TextView) findViewById(R.id.textView);
// Adapter
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, arraySpinner);
categories.setAdapter(adapter);
// Set onItemSelected listener to spinner
categories.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
TextView spinnerText = (TextView) view;
// Checking weather selected item is "Other" or not
if (spinnerText.getText().equals("Other"))
{
// Hide TextView
textView.setVisibility(View.INVISIBLE); // or View.GONE
}
}
#Override
public void onNothingSelected(AdapterView<?> adapterView) {
}
});
.............
...................
Hope this will help

you can Implement OnItemSelected in the spinner and do the things what you want.
categories.setOnItemSelectedListener(new OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parentView, View selectedItemView, int position, long id) {
if(arraySpinner!=null && arraySpinner[position].equalIgnoreCase("Other")){
// your code here
}
}
#Override
public void onNothingSelected(AdapterView<?> parentView) {
// your code here
}
});

Item selection in spinner doesn't detect in MyOnItemSelectedListener

I have activity with 3 spinners and selection of 1st spinner is related to 2nd and 2nd selection is related to the 3rd, so I have the spinner code one inside one.
CrustSp, SizeSp and extraDescriptionOneSP are the 3 spinners I have. I have loaded the items to the Spinners and I can select a value as well. But my problem is whenever i made a selection in CrustSp and SizeSp doesn't show in MyOnItemSelectedListener(). But if I made a selection in extraDescriptionOneSP it shows inside MyOnItemSelectedListener().
I can't figure where I have gone wrong, anyone can point out where I have gone wrong it will be really helpful.
This the code
crust = Utils.removeDuplicatesFromList(crust);
ArrayAdapter<String> dataAdapterCru = new ArrayAdapter<String>(
this, android.R.layout.simple_spinner_item, crust);
dataAdapterCru
.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
crustSP.setAdapter(dataAdapterCru);
crustSP.setOnItemSelectedListener(new MyOnItemSelectedListener(
ActivityPizzaCustomize.this) {
public void onNothingSelected(AdapterView<?> arg0) {
}
#Override
public void onItemSelected(AdapterView<?> parent,
View view, int position, long id) {
String crustSelectedItem = crustSP.getSelectedItem()
.toString();
List<String> resultSizes = getFilteredSizes(crustSelectedItem);
ArrayAdapter<String> dataAdapterDes = new ArrayAdapter<String>(
ActivityPizzaCustomize.this,
android.R.layout.simple_spinner_item,
resultSizes);
dataAdapterDes
.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
sizeSP.setAdapter(dataAdapterDes);
sizeSP.setOnItemSelectedListener(new MyOnItemSelectedListener(
ActivityPizzaCustomize.this) {
public void onNothingSelected(AdapterView<?> arg0) {
}
#Override
public void onItemSelected(AdapterView<?> parent,
View view, int position, long id) {
String sizeSelectedItem = sizeSP
.getSelectedItem().toString();
List<String> resultTopping = getFilteredToppings(sizeSelectedItem);
extraDescriptionOneSP
.setOnItemSelectedListener(new MyOnItemSelectedListener(
ActivityPizzaCustomize.this));
ArrayAdapter<String> dataAdapterExtraDesOne = new ArrayAdapter<String>(
ActivityPizzaCustomize.this,
android.R.layout.simple_spinner_item,
resultTopping);
dataAdapterExtraDesOne
.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
extraDescriptionOneSP
.setAdapter(dataAdapterExtraDesOne);
extraDescriptionOneSP
.setAdapter(new NothingSelectedSpinnerAdapter(
dataAdapterExtraDesOne,
R.layout.contact_spinner_row_nothing_selected,
ActivityPizzaCustomize.this));
}
});
}
});
MyOnItemSelectedListener method,
public class MyOnItemSelectedListener implements OnItemSelectedListener {
Activity activity;
String StrOneSPPosition;
public MyOnItemSelectedListener(Activity p_activity) {
activity = p_activity;
}
#Override
public void onItemSelected(AdapterView<?> parent, View view,
int position, long id) {
// check which spinner triggered the listener
switch (parent.getId()) {
case R.id.sp_crust: {
String StrCrustSPPosition = String.valueOf(crustSP
.getSelectedItemPosition());
System.out.println("crust = " + StrCrustSPPosition);
System.out.println("crust = " + position);
CrustSPPosition = Integer.parseInt(StrCrustSPPosition);
}

I don't see you using the selected position to determine the data for next spinner. BTW you should not make new adapter for each selection, instead reuse the once made adapter.