android: Fix first time setup scrolling bug

If you quickly scrolled from the second page to the first and then back, the next/back buttons would disappear.
This commit is contained in:
Charles Lombardo 2023-04-24 04:01:54 -04:00 committed by bunnei
parent 45d81dc6bd
commit d8c102444c
2 changed files with 17 additions and 18 deletions

View file

@ -110,23 +110,24 @@ class SetupFragment : Fragment() {
} }
binding.viewPager2.registerOnPageChangeCallback(object : OnPageChangeCallback() { binding.viewPager2.registerOnPageChangeCallback(object : OnPageChangeCallback() {
override fun onPageScrolled( var previousPosition: Int = 0
position: Int,
positionOffset: Float,
positionOffsetPixels: Int
) {
super.onPageScrolled(position, positionOffset, positionOffsetPixels)
if (position == 0) {
hideView(binding.buttonBack)
} else {
showView(binding.buttonBack)
}
if (position == pages.size - 1 || position == 0) { override fun onPageSelected(position: Int) {
super.onPageSelected(position)
if (position == 1 && previousPosition == 0) {
showView(binding.buttonNext)
showView(binding.buttonBack)
} else if (position == 0 && previousPosition == 1) {
hideView(binding.buttonBack)
hideView(binding.buttonNext) hideView(binding.buttonNext)
} else { } else if (position == pages.size - 1 && previousPosition == pages.size - 2) {
hideView(binding.buttonNext)
} else if (position == pages.size - 2 && previousPosition == pages.size - 1) {
showView(binding.buttonNext) showView(binding.buttonNext)
} }
previousPosition = position
} }
}) })
@ -154,10 +155,6 @@ class SetupFragment : Fragment() {
} }
private fun showView(view: View) { private fun showView(view: View) {
if (view.visibility == View.VISIBLE) {
return
}
view.apply { view.apply {
alpha = 0f alpha = 0f
visibility = View.VISIBLE visibility = View.VISIBLE
@ -169,7 +166,7 @@ class SetupFragment : Fragment() {
} }
private fun hideView(view: View) { private fun hideView(view: View) {
if (view.visibility == View.GONE) { if (view.visibility == View.INVISIBLE) {
return return
} }

View file

@ -22,6 +22,7 @@
android:layout_height="wrap_content" android:layout_height="wrap_content"
android:layout_margin="16dp" android:layout_margin="16dp"
android:text="@string/next" android:text="@string/next"
android:visibility="invisible"
app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent" /> app:layout_constraintEnd_toEndOf="parent" />
@ -32,6 +33,7 @@
android:layout_height="wrap_content" android:layout_height="wrap_content"
android:layout_margin="16dp" android:layout_margin="16dp"
android:text="@string/back" android:text="@string/back"
android:visibility="invisible"
app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent" /> app:layout_constraintStart_toStartOf="parent" />