From e445774ab5d76b35e527bfc873da6b9b1185b058 Mon Sep 17 00:00:00 2001
From: Thales Lima <tsuharesu@google.com>
Date: Tue, 20 Jul 2021 16:46:38 +0100
Subject: [PATCH] launcher: correct page spacing for multiple panels

This fixes 2 things:
- adding the correct space between pages as insets (eg camera) were
being discarded
- adding the space between pages instead of between panels as was before

This solution should work with more panels and don't create problems for
phones, where panels = 1.

Fixes 193194192
Test: manual testing in unfolded state in portrait and landscape, both
rotations

Change-Id: Ia3b148ceb773c6d5b6f8848ced07d7f9c1459e92
---
 src/com/android/launcher3/PagedView.java |  9 ++++++--
 src/com/android/launcher3/Workspace.java | 26 +++++++++++-------------
 2 files changed, 19 insertions(+), 16 deletions(-)

diff --git a/src/com/android/launcher3/PagedView.java b/src/com/android/launcher3/PagedView.java
index 20f5f9bb60..74b0d9c93e 100644
--- a/src/com/android/launcher3/PagedView.java
+++ b/src/com/android/launcher3/PagedView.java
@@ -709,6 +709,7 @@ public abstract class PagedView<T extends View & PageIndicator> extends ViewGrou
         final int scrollOffsetStart = mOrientationHandler.getScrollOffsetStart(this, mInsets);
         final int scrollOffsetEnd = mOrientationHandler.getScrollOffsetEnd(this, mInsets);
         boolean pageScrollChanged = false;
+        int panelCount = getPanelCount();
 
         for (int i = startIndex, childStart = scrollOffsetStart; i != endIndex; i += delta) {
             final View child = getPageAt(i);
@@ -726,11 +727,15 @@ public abstract class PagedView<T extends View & PageIndicator> extends ViewGrou
                     pageScrollChanged = true;
                     outPageScrolls[i] = pageScroll;
                 }
-                childStart += primaryDimension + mPageSpacing + getChildGap();
+                childStart += primaryDimension + getChildGap();
+
+                // This makes sure that the space is added after the page, not after each panel
+                if (i % panelCount == panelCount - 1) {
+                    childStart += mPageSpacing;
+                }
             }
         }
 
-        int panelCount = getPanelCount();
         if (panelCount > 1) {
             for (int i = 0; i < childCount; i++) {
                 // In case we have multiple panels, always use left panel's page scroll for all
diff --git a/src/com/android/launcher3/Workspace.java b/src/com/android/launcher3/Workspace.java
index a585be63a0..6c0e893ad8 100644
--- a/src/com/android/launcher3/Workspace.java
+++ b/src/com/android/launcher3/Workspace.java
@@ -315,9 +315,19 @@ public class Workspace extends PagedView<WorkspacePageIndicator>
         // Increase our bottom insets so we don't overlap with the taskbar.
         mInsets.bottom += grid.nonOverlappingTaskbarInset;
 
-        if (grid.isTwoPanels) {
-            setPageSpacing(0); // we have two pages and we don't want any spacing
+        if (mWorkspaceFadeInAdjacentScreens) {
+            // In landscape mode the page spacing is set to the default.
+            setPageSpacing(grid.edgeMarginPx);
+        } else {
+            // In portrait, we want the pages spaced such that there is no
+            // overhang of the previous / next page into the current page viewport.
+            // We assume symmetrical padding in portrait mode.
+            int maxInsets = Math.max(insets.left, insets.right);
+            int maxPadding = Math.max(grid.edgeMarginPx, padding.left + 1);
+            setPageSpacing(Math.max(maxInsets, maxPadding));
+        }
 
+        if (grid.isTwoPanels) {
             // Add left widget panel if it isn't already there
             if (!mWorkspaceScreens.containsKey(LEFT_PANEL_ID)) {
                 int newCurrentPage = mCurrentPage + 1;
@@ -325,18 +335,6 @@ public class Workspace extends PagedView<WorkspacePageIndicator>
                 setCurrentPage(newCurrentPage);
             }
         } else {
-            if (mWorkspaceFadeInAdjacentScreens) {
-                // In landscape mode the page spacing is set to the default.
-                setPageSpacing(grid.edgeMarginPx);
-            } else {
-                // In portrait, we want the pages spaced such that there is no
-                // overhang of the previous / next page into the current page viewport.
-                // We assume symmetrical padding in portrait mode.
-                int maxInsets = Math.max(insets.left, insets.right);
-                int maxPadding = Math.max(grid.edgeMarginPx, padding.left + 1);
-                setPageSpacing(Math.max(maxInsets, maxPadding));
-            }
-
             // Remove left widget panel if it is present
             if (mWorkspaceScreens.containsKey(LEFT_PANEL_ID)) {
                 int newCurrentPage = mCurrentPage - 1;