Type mismatch in ArrayOfNulls with Kotlin

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I got a problem when converting my java code to kotlin.

This line of code is what making me the problem

 dots = arrayOfNulls<TextView>(layouts.size)

it said:

Type mismatch. Required: Array(TextView)? - Found: Array(TextView?)

Let you here the whole code and hope you can give me hand to figure out what's wrong.

class WelcomeActivity : AppCompatActivity() {

private var viewPager: ViewPager? = null
private var myViewPagerAdapter: MyViewPagerAdapter? = null
private var dotsLayout: LinearLayout? = null
private var dots: Array<TextView>? = null
private var layouts: IntArray? = null
private var btnSkip: Button? = null
private var btnNext: Button? = null
private var prefManager: PrefManager? = null

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)

    // Checking for first time launch - before calling setContentView()
    prefManager = PrefManager(this)
    if (!prefManager!!.isFirstTimeLaunch) {
        launchHomeScreen()
        finish()
    }

    // Making notification bar transparent
    if (Build.VERSION.SDK_INT >= 21) {
        window.decorView.systemUiVisibility = View.SYSTEM_UI_FLAG_LAYOUT_STABLE or View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
    }

    setContentView(R.layout.welcomescreen)

    viewPager = findViewById(R.id.view_pager) as ViewPager
    dotsLayout = findViewById(R.id.layoutDots) as LinearLayout
    btnSkip = findViewById(R.id.btn_skip) as Button
    btnNext = findViewById(R.id.btn_next) as Button


    // layouts of all welcome sliders
    // add few more layouts if you want
    layouts = intArrayOf(R.layout.welcomescreen_slide1, R.layout.welcomescreen_slide2, R.layout.welcomescreen_slide3, R.layout.welcomescreen_slide4)

    // adding bottom dots
    addBottomDots(0)

    // making notification bar transparent
    changeStatusBarColor()

    myViewPagerAdapter = MyViewPagerAdapter()
    viewPager!!.adapter = myViewPagerAdapter
    viewPager!!.addOnPageChangeListener(viewPagerPageChangeListener)

    btnSkip!!.setOnClickListener { launchHomeScreen() }

    btnNext!!.setOnClickListener {
        // checking for last page
        // if last page home screen will be launched
        val current = getItem(+1)
        if (current < layouts!!.size) {
            // move to next screen
            viewPager!!.currentItem = current
        } else {
            launchHomeScreen()
        }
    }
}

private fun addBottomDots(currentPage: Int) {
    dots = arrayOfNulls<TextView>(layouts.size)

    val colorsActive = resources.getIntArray(R.array.array_dot_active)
    val colorsInactive = resources.getIntArray(R.array.array_dot_inactive)

    dotsLayout!!.removeAllViews()
    for (i in dots!!.indices) {
        dots[i] = TextView(this)
        dots!![i].text = Html.fromHtml("&#8226;")
        dots!![i].textSize = 35f
        dots!![i].setTextColor(colorsInactive[currentPage])
        dotsLayout!!.addView(dots!![i])
    }

    if (dots!!.size > 0)
        dots!![currentPage].setTextColor(colorsActive[currentPage])
}

Thanks in advance.

[EDIT]: Also, I noticed an error in a for statement, here:

for (i in dots!!.indices) {
        dots[i] = TextView(this)
        dots!![i].text = Html.fromHtml("&#8226;")
        dots!![i].textSize = 35f
        dots!![i].setTextColor(colorsInactive[currentPage])
        dotsLayout!!.addView(dots!![i])
    }

First, in the first line said Unresolve reference indices; then in second line say that dots[i] cannot smart cast to 'Array?' because it's a mutable property and finally in the lines behind every dot before dots!![i] says "Only safe (?) or not-null asserted (!!.) calls are allowed on a nullable receiver of type TextView?

2 Answers

Use:

private lateinit var dots: Array<TextView?>

Instead of:

private var dots: Array<TextView>? = null
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