Shrink image sizes of attachments in Reply app.

lib/studies/reply/mail_card_preview.dart

@@ -1,4 +1,5 @@
 import 'package:animations/animations.dart';
+import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:gallery/layout/adaptive.dart';
 import 'package:gallery/studies/reply/colors.dart';
@@ -255,6 +256,16 @@ class _MailPreview extends StatelessWidget {
 class _PicturePreview extends StatelessWidget {
   const _PicturePreview();
 
+  bool _shouldShrinkImage() {
+    switch (defaultTargetPlatform) {
+      case TargetPlatform.iOS:
+      case TargetPlatform.android:
+        return true;
+      default:
+        return false;
+    }
+  }
+
   @override
   Widget build(BuildContext context) {
     return SizedBox(
@@ -269,6 +280,7 @@ class _PicturePreview extends StatelessWidget {
               'reply/attachments/paris_${index + 1}.jpg',
               gaplessPlayback: true,
               package: 'flutter_gallery_assets',
+              cacheWidth: _shouldShrinkImage() ? 200 : null,
             ),
           );
         },

lib/studies/reply/mail_view_page.dart

@@ -1,3 +1,4 @@
+import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:gallery/studies/reply/model/email_model.dart';
 import 'package:gallery/studies/reply/model/email_store.dart';
@@ -134,6 +135,16 @@ class _MailViewBody extends StatelessWidget {
 class _PictureGrid extends StatelessWidget {
   const _PictureGrid();
 
+  bool _shouldShrinkImage() {
+    switch (defaultTargetPlatform) {
+      case TargetPlatform.iOS:
+      case TargetPlatform.android:
+        return true;
+      default:
+        return false;
+    }
+  }
+
   @override
   Widget build(BuildContext context) {
     return GridView.builder(
@@ -151,6 +162,7 @@ class _PictureGrid extends StatelessWidget {
           gaplessPlayback: true,
           package: 'flutter_gallery_assets',
           fit: BoxFit.fill,
+          cacheWidth: _shouldShrinkImage() ? 500 : null,
         );
       },
     );

lib/studies/shrine/app.dart

@@ -151,6 +151,7 @@ class _ShrineAppState extends State<ShrineApp>
 
     return ScopedModel<AppStateModel>(
       model: _model.value,
+      // ignore: deprecated_member_use
       child: WillPopScope(
         onWillPop: _onWillPop,
         child: MaterialApp(