Remember focus after navigating from Fragment to Fragment

Author: NicolasBourdin88

app/src/main/java/com/infomaniak/mail/ui/main/settings/SettingsFragment.kt

@@ -37,6 +37,7 @@ import com.infomaniak.mail.data.LocalSettings
 import com.infomaniak.mail.data.models.FeatureFlag
 import com.infomaniak.mail.databinding.FragmentSettingsBinding
 import com.infomaniak.mail.ui.MainViewModel
+import com.infomaniak.mail.utils.UiUtils.saveFocusWhenNavigatingBack
 import com.infomaniak.mail.utils.extensions.animatedNavigation
 import com.infomaniak.mail.utils.extensions.launchSyncAutoConfigActivityForResult
 import com.infomaniak.mail.utils.extensions.observeNotNull
@@ -53,6 +54,11 @@ class SettingsFragment : Fragment() {
     @Inject
     lateinit var localSettings: LocalSettings
 
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        saveFocusWhenNavigatingBack(getLayout = { binding.linearLayoutContainer }, lifecycle)
+    }
+
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View {
         return FragmentSettingsBinding.inflate(inflater, container, false).also { binding = it }.root
     }

app/src/main/java/com/infomaniak/mail/ui/main/settings/appearance/swipe/SwipeActionsSettingsFragment.kt

@@ -30,6 +30,7 @@ import com.infomaniak.mail.R
 import com.infomaniak.mail.data.LocalSettings
 import com.infomaniak.mail.data.LocalSettings.SwipeAction
 import com.infomaniak.mail.databinding.FragmentSwipeActionsSettingsBinding
+import com.infomaniak.mail.utils.UiUtils.saveFocusWhenNavigatingBack
 import com.infomaniak.mail.utils.extensions.animatedNavigation
 import com.infomaniak.mail.utils.extensions.setSystemBarsColors
 import dagger.hilt.android.AndroidEntryPoint
@@ -43,6 +44,11 @@ class SwipeActionsSettingsFragment : Fragment() {
     @Inject
     lateinit var localSettings: LocalSettings
 
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        saveFocusWhenNavigatingBack(getLayout = { binding.linearLayoutContainer }, lifecycle)
+    }
+
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View {
         return FragmentSwipeActionsSettingsBinding.inflate(inflater, container, false).also { binding = it }.root
     }

app/src/main/java/com/infomaniak/mail/ui/main/settings/privacy/DataManagementSettingsFragment.kt

@@ -28,6 +28,7 @@ import com.infomaniak.lib.core.utils.safeBinding
 import com.infomaniak.mail.BuildConfig
 import com.infomaniak.mail.MatomoMail.trackEvent
 import com.infomaniak.mail.databinding.FragmentDataManagementSettingsBinding
+import com.infomaniak.mail.utils.UiUtils.saveFocusWhenNavigatingBack
 import com.infomaniak.mail.utils.extensions.animatedNavigation
 import com.infomaniak.mail.utils.extensions.setSystemBarsColors
 import dagger.hilt.android.AndroidEntryPoint
@@ -37,6 +38,11 @@ class DataManagementSettingsFragment : Fragment() {
 
     private var binding: FragmentDataManagementSettingsBinding by safeBinding()
 
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        saveFocusWhenNavigatingBack(getLayout = { binding.linearLayoutContainer }, lifecycle)
+    }
+
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View {
         return FragmentDataManagementSettingsBinding.inflate(inflater, container, false).also { binding = it }.root
     }

app/src/main/java/com/infomaniak/mail/ui/main/user/AccountFragment.kt

@@ -47,6 +47,7 @@ import com.infomaniak.mail.utils.ConfettiUtils
 import com.infomaniak.mail.utils.ConfettiUtils.ConfettiType
 import com.infomaniak.mail.utils.LogoutUser
 import com.infomaniak.mail.utils.PlayServicesUtils
+import com.infomaniak.mail.utils.UiUtils.saveFocusWhenNavigatingBack
 import com.infomaniak.mail.utils.extensions.animatedNavigation
 import com.infomaniak.mail.utils.extensions.bindAlertToViewLifecycle
 import com.infomaniak.mail.utils.extensions.setSystemBarsColors
@@ -83,6 +84,11 @@ class AccountFragment : Fragment(), MailboxListFragment {
     @Inject
     lateinit var descriptionDialog: DescriptionAlertDialog
 
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        saveFocusWhenNavigatingBack(getLayout = { binding.constraintLayoutContainer }, lifecycle)
+    }
+
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View {
         return FragmentAccountBinding.inflate(inflater, container, false).also { binding = it }.root
     }

app/src/main/java/com/infomaniak/mail/utils/UiUtils.kt

@@ -22,14 +22,20 @@ import android.animation.ValueAnimator
 import android.content.Context
 import android.graphics.Color
 import android.os.Build
+import android.view.View
+import android.view.ViewGroup
 import android.view.Window
 import android.widget.TextView
 import androidx.annotation.ColorInt
 import androidx.annotation.FloatRange
+import androidx.annotation.IdRes
 import androidx.appcompat.content.res.AppCompatResources
 import androidx.core.graphics.toColor
 import androidx.core.graphics.toColorInt
 import androidx.core.view.isGone
+import androidx.lifecycle.DefaultLifecycleObserver
+import androidx.lifecycle.Lifecycle
+import androidx.lifecycle.LifecycleOwner
 import com.infomaniak.mail.R
 import com.infomaniak.mail.data.models.correspondent.Correspondent
 import com.infomaniak.mail.utils.extensions.updateNavigationBarColor
@@ -156,4 +162,32 @@ object UiUtils {
     }
 
     fun dividerDrawable(context: Context) = AppCompatResources.getDrawable(context, R.drawable.divider)
+
+    fun saveFocusWhenNavigatingBack(getLayout: () -> ViewGroup, lifecycle: Lifecycle) {
+        val lifecycleObserver = object : DefaultLifecycleObserver {
+            @IdRes
+            private var lastFocusViewId: Int? = null
+
+            override fun onDestroy(owner: LifecycleOwner) {
+                lifecycle.removeObserver(this)
+                super.onDestroy(owner)
+            }
+
+            override fun onStart(owner: LifecycleOwner) {
+                super.onStart(owner)
+                lastFocusViewId?.let { viewId ->
+                    getLayout().findViewById<View>(viewId).requestFocus()
+                }
+            }
+
+            override fun onStop(owner: LifecycleOwner) {
+                getLayout().focusedChild?.let {
+                    lastFocusViewId = it.id
+                }
+                super.onStop(owner)
+            }
+        }
+
+        lifecycle.addObserver(lifecycleObserver)
+    }
 }

app/src/main/res/layout/fragment_account.xml

@@ -35,6 +35,7 @@
             android:layout_weight="1">
 
             <androidx.constraintlayout.widget.ConstraintLayout
+                android:id="@+id/constraintLayoutContainer"
                 android:layout_width="match_parent"
                 android:layout_height="match_parent">
 

app/src/main/res/layout/fragment_data_management_settings.xml

@@ -26,6 +26,7 @@
         android:layout_height="match_parent">
 
         <LinearLayout
+            android:id="@+id/linearLayoutContainer"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:orientation="vertical">

app/src/main/res/layout/fragment_settings.xml

@@ -31,6 +31,7 @@
         android:scrollbars="none">
 
         <LinearLayout
+            android:id="@+id/linearLayoutContainer"
             android:layout_width="match_parent"
             android:layout_height="match_parent"
             android:clipToPadding="false"

app/src/main/res/layout/fragment_swipe_actions_settings.xml

@@ -29,6 +29,7 @@
         android:layout_height="match_parent">
 
         <LinearLayout
+            android:id="@+id/linearLayoutContainer"
             android:layout_width="match_parent"
             android:layout_height="match_parent"
             android:clipChildren="false"