allow back navigation on symptom intro and calendar (#1856)

replace app bar icon with X to indicate abort

Co-authored-by: Matthias Urhahn <matthias.urhahn@sap.com>

Corona-Warn-App/src/main/java/de/rki/coronawarnapp/ui/submission/symptoms/calendar/SubmissionSymptomCalendarFragment.kt

@@ -3,7 +3,6 @@ package de.rki.coronawarnapp.ui.submission.symptoms.calendar
 import android.content.res.ColorStateList
 import android.os.Bundle
 import android.view.View
-import androidx.activity.OnBackPressedCallback
 import androidx.fragment.app.Fragment
 import de.rki.coronawarnapp.R
 import de.rki.coronawarnapp.databinding.FragmentSubmissionSymptomCalendarBinding
@@ -75,13 +74,6 @@ class SubmissionSymptomCalendarFragment : Fragment(R.layout.fragment_submission_
             updateButtons(it)
         }
 
-        val backCallback: OnBackPressedCallback = object : OnBackPressedCallback(true) {
-            override fun handleOnBackPressed() {
-                viewModel.onCalendarPreviousClicked()
-            }
-        }
-        requireActivity().onBackPressedDispatcher.addCallback(viewLifecycleOwner, backCallback)
-
         binding.submissionSymptomCalendarHeader.headerButtonBack.buttonIcon.setOnClickListener {
             viewModel.onCalendarPreviousClicked()
         }

Corona-Warn-App/src/main/java/de/rki/coronawarnapp/ui/submission/symptoms/introduction/SubmissionSymptomIntroductionFragment.kt

@@ -3,7 +3,6 @@ package de.rki.coronawarnapp.ui.submission.symptoms.introduction
 import android.content.res.ColorStateList
 import android.os.Bundle
 import android.view.View
-import androidx.activity.OnBackPressedCallback
 import androidx.fragment.app.Fragment
 import de.rki.coronawarnapp.R
 import de.rki.coronawarnapp.databinding.FragmentSubmissionSymptomIntroBinding
@@ -65,13 +64,6 @@ class SubmissionSymptomIntroductionFragment : Fragment(R.layout.fragment_submiss
             updateButtons(it)
         }
 
-        val backCallback: OnBackPressedCallback = object : OnBackPressedCallback(true) {
-            override fun handleOnBackPressed() {
-                viewModel.onPreviousClicked()
-            }
-        }
-        requireActivity().onBackPressedDispatcher.addCallback(viewLifecycleOwner, backCallback)
-
         binding.submissionSymptomHeader.headerButtonBack.buttonIcon.setOnClickListener { viewModel.onPreviousClicked() }
     }
 

Corona-Warn-App/src/main/res/layout/fragment_submission_symptom_calendar.xml

@@ -17,7 +17,7 @@
             layout="@layout/include_header"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
-            app:icon="@{@drawable/ic_back}"
+            app:icon="@{@drawable/ic_close}"
             app:title="@{@string/submission_symptom_calendar_title}" />
 
         <ScrollView

Corona-Warn-App/src/main/res/layout/fragment_submission_symptom_intro.xml

@@ -11,7 +11,7 @@
             layout="@layout/include_header"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
-            app:icon="@{@drawable/ic_back}"
+            app:icon="@{@drawable/ic_close}"
             app:title="@{@string/submission_symptom_title}" />
 
         <ScrollView