Android - some basic control & resource operations

• get control by resource id

(Button)findViewById(R.id.btnMtFaberLine);

• download population

dropdownDirection = (Spinner)findViewById(R.id.spinnerWelcome);
String[] items = new String[]{"Entry","Exit"};
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_dropdown_item, items);
dropdownDirection.setAdapter(adapter);

• set textview text and bold

TextView textViewUserName = (TextView)findViewById(R.id.usernameTV);
textViewUserName.setTypeface(null, Typeface.BOLD);
textViewUserName.setText("User: " + username);

• image view operation

ImageView img1 = (ImageView) findViewById(R.id.imageView1);
img1.setImageDrawable(null);
img1.setImageResource(R.drawable.check);

• play audio

MediaPlayer mp = MediaPlayer.create(getApplicationContext(), R.raw.wrong);
mp.start();

• format datetime

SimpleDateFormat dtFormater = new SimpleDateFormat("dd/MM/yyyy HH:mm:ss",
        Locale.ENGLISH);
dtFormater.format(new Date());