title: property getter or setter expected
body: <p>I want to use a bitmap var in a class. It makes 'property getter or setter expected' error. What is the problem?
  The error shows around 'bmp? : Bitmap = null'.
  How can I solve the problem?</p>
  
  <p>And I don't understand why I must use getter or setter for private properties in a class.</p>
  
  <pre><code>class MyView(context: Context?) : View(context) {
      private var bmp? : Bitmap = null
  
      init {
          bmp = BitmapFactory.decodeResource(resources, R.mipmap.ic_launcher)
      }
  
      override fun onDraw(canvas: Canvas?) {
          super.onDraw(canvas)
          canvas?.drawColor(Color.BLUE)
          canvas?.drawBitmap(bmp,10f,10f, null)
      }
  }
  </code></pre>