"NullPointerException" is showing when trying to get selected spinner item during a buttin OnClickListener

Question

I am have made a Custom Adapter list for the spinner. When i select an item from the spinner, i can get the selected item and can Toast it in the "setOnItemSelectedListener()";

spinner = findViewById(R.id.spinnerId);
CustomAdapter arrayAdapter = new CustomAdapter(this, countryLists, population, flags);
spinner.setAdapter(arrayAdapter);

spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
            if(isSelected == true){
                isSelected = false;
            }
            else {                   
                Toast.makeText(getApplicationContext(),countryLists[position]+" is selected", Toast.LENGTH_SHORT).show();
            }
        }

        @Override
        public void onNothingSelected(AdapterView<?> parent) {

        }
    });

the above code is working fine.

Now i want to pass the selected item value from a button "OnClickListener" like the below code.

button.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            String value = spinner.getSelectedItem().toString();
            textView.setText(value );
        }
    });

but Error is showing "java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference"

What could be the problem??

@Laureal check this link :- https://stackoverflow.com/a/49491407/7319704 — Abhinav Gupta, Mar 27 '18 at 09:02

score 3 · Answer 1 · answered Mar 27 '18 at 09:01

3

The problem is you may have not selected an item. Hence, just check null before using:

button.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            if(spinner.getSelectedItem() != null) {
                String value = spinner.getSelectedItem().toString();
                textView.setText(value );
            }
        }
    });

answered Mar 27 '18 at 09:01

Cao Minh Vu

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When you select an item, please try to call spinner.setSelection(id) – Cao Minh Vu Mar 27 '18 at 09:06

score 0 · Answer 2 · answered Mar 27 '18 at 09:01

try to construct like this:

String global_variable; //this would go on the Declaration



spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
            global_variable = String.valueOf(spinner.getSelectedItem()
        }


button.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        String value = spinner.getSelectedItem().toString();
        textView.setText(global_variable);
    }
});

"NullPointerException" is showing when trying to get selected spinner item during a buttin OnClickListener

2 Answers2