how to autocomplete a spinner in android studio code example

Example 1: spinner android

// Spinner element
      Spinner spinner = (Spinner) findViewById(R.id.spinner);
      
      // Spinner click listener
      spinner.setOnItemSelectedListener(this);
      
      // Spinner Drop down elements
      List<String> categories = new ArrayList<String>();
      categories.add("Automobile");
      categories.add("Business Services");
      categories.add("Computers");
      categories.add("Education");
      categories.add("Personal");
      categories.add("Travel");
      
      // Creating adapter for spinner
      ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, categories);
      
      // Drop down layout style - list view with radio button
      dataAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
      
      // attaching data adapter to spinner
      spinner.setAdapter(dataAdapter);

Example 2: how to access a spinner from another activity in android

First save the position of selected data from spinner in a String variable,

int positionOfSelectedDataFromSpinner;

spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {

    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
       positionOfSelectedDataFromSpinner= position;
}
Then on button click send intent to Another activity with putExtra

Intent i = new Intent (this, activity2.class);

i.putExtra("position", positionOfSelectedDataFromSpinner);
startActivity(i);
get int from getIntent in another activity

Intent intent = getIntent();
int positionToShowToSpinner = intent.getStringExtra("position");
then set the position to spinner

spinner.setSelection(positionToShowToSpinner);
I think this my solve your problem.