I have a Button in my viewpager2 (Page: UserDataFragment) which navigates the user to another screen (UserDataChangeEmailFragment), where they can change their password etc. The problem I encounter is that the back button on this screen is not working (e.g when the user presses back and or the toolbar button, the user is not navigated back to UserDataFragment).
The only error I then get is: SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length.
Graph Picture (trying to navigate from x to y):
Graph Structure
UserDataHolderFragment (Holder for the ViewPager2)
|
|--UserDataFragment (First Page of the ViewPager2, here is the **Button**)
| |
| |-- UserDataChangeEmailFragment (Back button not working)
|
|
|--UserDataAddressFragment (Second Page of the ViewPager2)
Graph Code (Deleted unnecessary stuff)
<navigation android:id="@+id/nav_user_data"
app:startDestination="@id/userDataHolderFragment">
<fragment
android:id="@+id/userDataHolderFragment"
android:name="com.rsb3000.app.framework.ui.view.fragment.user.loggedIn.userdata.UserDataHolderFragment"
tools:layout="@layout/fragment_user_data_holder" >
<action
android:id="@+id/action_userDataHolderFragment_to_userDataChangeEmailFragment"
app:destination="@id/userDataChangeEmailFragment" />
<action
android:id="@+id/action_userDataHolderFragment_to_userDataChangePasswordFragment"
app:destination="@id/userDataChangePasswordFragment" />
</fragment>
<fragment
android:id="@+id/userDataFragment"
android:name="com.rsb3000.app.framework.ui.view.fragment.user.loggedIn.userdata.UserDataFragment"
tools:layout="@layout/fragment_user_data">
</fragment>
<fragment
android:id="@+id/userDataAddressFragment"
android:name="com.rsb3000.app.framework.ui.view.fragment.user.loggedIn.userdata.UserDataAddressFragment"
tools:layout="@layout/fragment_user_data_address" >
</fragment>
<fragment
android:id="@+id/userDataChangeEmailFragment"
android:name="com.rsb3000.app.framework.ui.view.fragment.user.loggedIn.userdata.UserDataChangeEmailFragment"
tools:layout="@layout/fragment_user_data_change_email" />
</navigation>
UserDataHolderFragment Code (Navigation button here)
@AndroidEntryPoint
class UserDataHolderFragment : Fragment(R.layout.fragment_user_data_holder) {
private val binding: FragmentUserDataHolderBinding by viewBinding(FragmentUserDataHolderBinding::bind)
val userDataViewPagerAdapter: UserDataViewPagerAdapter get() = UserDataViewPagerAdapter(SnackbarUtils(), this)
@Inject lateinit var tabLayoutHelper: TabLayoutHelper
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
binding.headline.userStandardToolbar.setupWithNavController(findNavController(), AppBarConfiguration(findNavController().graph))
bindObjects()
bindTablayout()
}
private fun bindObjects() {
with(binding) {
lifecycleOwner = viewLifecycleOwner
vpUserData.adapter = userDataViewPagerAdapter
}
}
private fun bindTablayout() {
tabLayoutHelper.init(binding.tlUserData, binding.vpUserData) { tab, position ->
when(position) {
0 -> tab.text = requireContext().getString(R.string.fragment_user_data_holder_user_data_tab)
1 -> tab.text = requireContext().getString(R.string.fragment_user_data_holder_user_address_tab)
}
}
}
override fun onDestroyView() {
super.onDestroyView()
tabLayoutHelper.onDestroyView()
binding.vpUserData.adapter = null
}
}
UserDataFragment
private fun bindBtnClicks() {
btnGoToChangeAddress.setOnClickListener {
findNavController().navigate(
UserDataHolderFragmentDirections.actionUserDataFragmentHolderToUserDataChangeEmailFragment()
)
}
}
UserDataChangeEmailFragment (BACK BUTTON NOT WORKING HERE)
class UserDataChangeEmailFragment : Fragment(R.layout.fragment_user_data_change_email) {
private val binding: FragmentUserDataChangeEmailBinding by viewBinding(FragmentUserDataChangeEmailBinding::bind)
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
binding.headline.userStandardToolbar.setupWithNavController(findNavController(), AppBarConfiguration(findNavController().graph))
}
}
