色指定

var tv01 = findViewById<TextView>(R.id.tv01)
tv01.setTextColor(Color.parseColor("#0000ff"))

tv01.setTextColor(Color.argb(50,255,255,255))

<resource>
    <color name="blue">#4682b4</color>
</resource>

tv01.setTextColor(getResources().getColor(R.color.blue))

tv01.setTextColor(getResources().getColor(android.R.color.holo_purple))