Merge "Allow SafetyCenter Subpages to scroll up after collapsing More issues" into udc-dev

3 files changed, 136 insertions, 1 deletions

diff --git a/PermissionController/src/com/android/permissioncontroller/safetycenter/ui/SafetyCenterDashboardFragment.java b/PermissionController/src/com/android/permissioncontroller/safetycenter/ui/SafetyCenterDashboardFragment.java
index dd90fd559..940cb2f69 100644
--- a/PermissionController/src/com/android/permissioncontroller/safetycenter/ui/SafetyCenterDashboardFragment.java
+++ b/PermissionController/src/com/android/permissioncontroller/safetycenter/ui/SafetyCenterDashboardFragment.java
@@ -41,6 +41,7 @@ import android.util.Log;
 
 import androidx.annotation.Nullable;
 import androidx.annotation.RequiresApi;
+import androidx.preference.Preference;
 import androidx.preference.PreferenceCategory;
 import androidx.preference.PreferenceGroup;
 
@@ -65,6 +66,7 @@ public final class SafetyCenterDashboardFragment extends SafetyCenterFragment {
     private static final String ISSUES_GROUP_KEY = "issues_group";
     private static final String ENTRIES_GROUP_KEY = "entries_group";
     private static final String STATIC_ENTRIES_GROUP_KEY = "static_entries_group";
+    private static final String SPACER_KEY = "spacer";
 
     private SafetyStatusPreference mSafetyStatusPreference;
     private final CollapsableGroupCardHelper mCollapsableGroupCardHelper =
@@ -116,6 +118,8 @@ public final class SafetyCenterDashboardFragment extends SafetyCenterFragment {
             mEntriesGroup = null;
             getPreferenceScreen().removePreference(mStaticEntriesGroup);
             mStaticEntriesGroup = null;
+            Preference spacerPreference = getPreferenceScreen().findPreference(SPACER_KEY);
+            getPreferenceScreen().removePreference(spacerPreference);
         }
         getSafetyCenterViewModel().getStatusUiLiveData().observe(this, this::updateStatus);
 
diff --git a/PermissionController/src/com/android/permissioncontroller/safetycenter/ui/SafetyCenterSubpageFragment.kt b/PermissionController/src/com/android/permissioncontroller/safetycenter/ui/SafetyCenterSubpageFragment.kt
index 8625e1959..5e45d2b3c 100644
--- a/PermissionController/src/com/android/permissioncontroller/safetycenter/ui/SafetyCenterSubpageFragment.kt
+++ b/PermissionController/src/com/android/permissioncontroller/safetycenter/ui/SafetyCenterSubpageFragment.kt
@@ -105,7 +105,9 @@ class SafetyCenterSubpageFragment : SafetyCenterFragment() {
             Log.w(TAG, "$sourceGroupId doesn't have any matching footer")
             subpageFooter.setVisible(false)
         }
-
+        // footer is ordered last by default
+        // in order to keep a spacer after the footer, footer needs to be the second from last
+        subpageFooter.setOrder(Int.MAX_VALUE - 2)
         subpageFooter.setSummary(footerText)
     }
 
diff --git a/PermissionController/src/com/android/permissioncontroller/safetycenter/ui/SpacerPreference.kt b/PermissionController/src/com/android/permissioncontroller/safetycenter/ui/SpacerPreference.kt
new file mode 100644
index 000000000..bb09783be
--- /dev/null
+++ b/PermissionController/src/com/android/permissioncontroller/safetycenter/ui/SpacerPreference.kt
@@ -0,0 +1,129 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.permissioncontroller.safetycenter.ui
+
+import android.content.Context
+import android.util.AttributeSet
+import android.view.View
+import android.view.ViewGroup
+import android.view.ViewTreeObserver
+import androidx.preference.Preference
+import androidx.preference.PreferenceScreen
+import androidx.preference.PreferenceViewHolder
+import com.android.permissioncontroller.R
+import com.android.settingslib.collapsingtoolbar.CollapsingToolbarBaseActivity
+import com.android.settingslib.widget.FooterPreference
+import kotlin.math.max
+
+/**
+ * A preference that adds an empty space to the bottom of a Safety Center subpage.
+ *
+ * Due to the logic of [CollapsingToolbarBaseActivity], its content won't be scrollable if it fits
+ * the single page. This logic conflicts with the UX of collapsible and expandable items of Safety
+ * Center, and with some other use cases (i.e. opening the page from Search might scroll to bottom
+ * while the scroll is disabled). In such cases user won't be able to expand the collapsed toolbar
+ * by scrolling the screen content.
+ *
+ * [SpacerPreference] makes the page to be slightly bigger than the screen size to unlock the scroll
+ * regardless of the content length and to mitigate this UX problem.
+ *
+ * If a [FooterPreference] is added to the same [PreferenceScreen], its order should be decreased to
+ * keep it with the last visible content above the [SpacerPreference].
+ */
+internal class SpacerPreference(context: Context, attrs: AttributeSet) :
+    Preference(context, attrs) {
+
+    init {
+        setLayoutResource(R.layout.preference_spacer)
+        isVisible = SafetyCenterUiFlags.getShowSubpages()
+        // spacer should be the last item on screen
+        setOrder(Int.MAX_VALUE - 1)
+    }
+
+    private var maxKnownToolbarHeight = 0
+    override fun onBindViewHolder(holder: PreferenceViewHolder) {
+        super.onBindViewHolder(holder)
+        val spacer = holder.itemView
+
+        // we should ensure we won't add multiple listeners to the same view,
+        // and Preferences API does not allow to do cleanups when onViewRecycled,
+        // so we are keeping a track of the added listener attaching it as a tag to the View
+        val listener: View.OnLayoutChangeListener = spacer.tag as? View.OnLayoutChangeListener
+            ?: object : View.OnLayoutChangeListener {
+                    override fun onLayoutChange(
+                        v: View?,
+                        left: Int,
+                        top: Int,
+                        right: Int,
+                        bottom: Int,
+                        oldLeft: Int,
+                        oldTop: Int,
+                        oldRight: Int,
+                        oldBottom: Int
+                    ) {
+                        adjustHeight(spacer)
+                    }}.also { spacer.tag = it }
+
+        spacer.removeOnLayoutChangeListener(listener)
+        spacer.addOnLayoutChangeListener(listener)
+    }
+
+    private fun adjustHeight(spacer: View) {
+        val root = spacer.rootView as? ViewGroup
+        if (root == null) {
+            return
+        }
+
+        val contentParent = root.findViewById<ViewGroup>(R.id.content_parent)
+        if (contentParent == null) {
+            return
+        }
+        // when opening the Subpage from Search the layout pass may be triggered
+        // differently due to the auto-scroll to highlight a specific item,
+        // and in this case we need to wait the content parent to be measured
+        if (contentParent.height == 0) {
+            val globalLayoutObserver = object : ViewTreeObserver.OnGlobalLayoutListener {
+                override fun onGlobalLayout() {
+                    contentParent.viewTreeObserver.removeOnGlobalLayoutListener(this)
+                    adjustHeight(spacer)
+                }
+            }
+            contentParent.viewTreeObserver.addOnGlobalLayoutListener(globalLayoutObserver)
+            return
+        }
+
+        val collapsingToolbar = root.findViewById<View>(R.id.collapsing_toolbar)
+        maxKnownToolbarHeight = max(maxKnownToolbarHeight, collapsingToolbar.height)
+
+        val contentHeight = spacer.top + maxKnownToolbarHeight
+        val desiredSpacerHeight = if (contentHeight > contentParent.height) {
+            // making it 0 height will remove if from recyclerview
+            1
+        } else {
+            // to unlock the scrolling we need spacer to go slightly beyond the screen
+            contentParent.height - contentHeight + 1
+        }
+
+        val layoutParams = spacer.layoutParams
+        if (layoutParams.height != desiredSpacerHeight) {
+            layoutParams.height = desiredSpacerHeight
+            spacer.layoutParams = layoutParams
+            // need to let RecyclerView to update scroll position
+            spacer.post(::notifyChanged)
+        }
+    }
+}