TextView extension functions to easily implement reactivity.

ScrollViewExt.kt

import android.view.View
import android.widget.ScrollView

fun ScrollView.smoothScrollToViewBottom(view: View) {
    val scrollViewHeight = height
    val outViewPosition = IntArray(2)

    view.getLocationOnScreen(outViewPosition)

    val viewY = outViewPosition[1]
    val bottom = viewY + view.height
    val scrollToY = scrollY + (bottom - scrollViewHeight)

    this.smoothScrollTo(0, scrollToY)
}

fun ScrollView.smoothScrollToViewTop(view: View) {
    val outViewPosition = IntArray(2)

    view.getLocationOnScreen(outViewPosition)

    val viewY = outViewPosition[1]
    val scrollToY = scrollY + viewY - view.height

    this.smoothScrollTo(0, scrollToY)
}

TextViewExt.kt

import android.widget.TextView
import androidx.core.widget.doAfterTextChanged

// Source: https://stackoverflow.com/questions/9385081/how-can-i-change-the-edittext-text-without-triggering-the-text-watcher

/**
 * Whenever the user makes a change to the text
 * the action parameter will be triggered.
 *
 * This function is meant to be used with [setTextIfDistinct]
 * to avoid triggering the action if the text hasn't changed from user input.
 */
inline fun TextView.onTextChanged(
	crossinline action: (String) -> Unit,
) {
	doAfterTextChanged {
		if (hasFocus()) {
			action(it.toString())
		}
	}
}

/**
 * Sets the text only if is distinct.
 *
 * This is useful to avoid triggering the action if the text hasn't changed from user input.
 *
 * This extension function is meant to be used with [onTextChanged].
 */
fun TextView.setTextIfDistinct(text: String?) {

	val hasFocus = hasFocus()

	if (hasFocus) {
		clearFocus()
	}

	if (this.text.toString() != text) {
		this.text = text
	}

	if (hasFocus) {
		requestFocus()
	}
}