From dd16986d79909efcb5db42a6127ff5b0753c12d8 Mon Sep 17 00:00:00 2001
From: Matthew Chen <matthew@signal.org>
Date: Tue, 12 Mar 2019 12:25:13 -0400
Subject: [PATCH] Avoid layout changes due to selection changes in media rail.

---
 SignalMessaging/Views/GalleryRailView.swift | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/SignalMessaging/Views/GalleryRailView.swift b/SignalMessaging/Views/GalleryRailView.swift
index 2e52f9e06..66690ab2a 100644
--- a/SignalMessaging/Views/GalleryRailView.swift
+++ b/SignalMessaging/Views/GalleryRailView.swift
@@ -64,14 +64,17 @@ public class GalleryRailCellView: UIView {
     private(set) var isSelected: Bool = false
 
     func setIsSelected(_ isSelected: Bool) {
+        let borderWidth: CGFloat = 2
         self.isSelected = isSelected
+
+        // Reserve space for the selection border whether or not the cell is selected.
+        layoutMargins = UIEdgeInsets(top: 0, left: borderWidth, bottom: 0, right: borderWidth)
+
         if isSelected {
-            layoutMargins = UIEdgeInsets(top: 0, left: 2, bottom: 0, right: 2)
             imageView.layer.borderColor = Theme.galleryHighlightColor.cgColor
-            imageView.layer.borderWidth = 2
-            imageView.layer.cornerRadius = 2
+            imageView.layer.borderWidth = borderWidth
+            imageView.layer.cornerRadius = borderWidth
         } else {
-            layoutMargins = .zero
             imageView.layer.borderWidth = 0
             imageView.layer.cornerRadius = 0
         }