Set Key and Value in spinner

Better approach to populate spinner with key and value should be:

Step 1: Create POJO class which will take care of key and value

public class Country {

    private String id;
    private String name;
    
    public Country(String id, String name) {
        this.id = id;
        this.name = name;
    }


    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }


    //to display object as a string in spinner
    @Override
    public String toString() {
        return name;
    }

    @Override
    public boolean equals(Object obj) {
        if(obj instanceof Country){
            Country c = (Country )obj;
            if(c.getName().equals(name) && c.getId()==id ) return true;
        }

        return false;
    }

}

Note: toString() method is important as it is responsible for displaying the data in spinner, you can modify toString() as per your need

Step 2: Prepare data to be loaded in spinner

 private void setData() {

        ArrayList<Country> countryList = new ArrayList<>();
        //Add countries

        countryList.add(new Country("1", "India"));
        countryList.add(new Country("2", "USA"));
        countryList.add(new Country("3", "China"));
        countryList.add(new Country("4", "UK"));

        //fill data in spinner 
        ArrayAdapter<Country> adapter = new ArrayAdapter<Country>(context, android.R.layout.simple_spinner_dropdown_item, countryList);
        spinner_country.setAdapter(adapter);
        spinner_country.setSelection(adapter.getPosition(myItem));//Optional to set the selected item.    
    }

Step 3: and finally get selected item’s key and value in onitemselected listener method of spinner

spinner_country.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {

                 Country country = (Country) parent.getSelectedItem();
                 Toast.makeText(context, "Country ID: "+country.getId()+",  Country Name : "+country.getName(), Toast.LENGTH_SHORT).show();    
            }

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