Unresolved reference: lang in this@MainActivity.runOnUiThread(java.lang.Runnable

Question

Any ideas why "lang" is not recognized? I found code in kotlin in this question.

user_11233871 · Answer

Runnable is class from lang package.

you should be import and use it.

import java.lang.Runnable


this@MainActivity.runOnUiThread(Runnable {
    progressBar.visibility = View.GONE
})