Media View improvements (#128)

CHANGELOG.md

@@ -1,3 +1,9 @@
+## Unreleased
+
+### Changed
+
+- Changed image viewer dismissal to be more fun. The image now also moves on the x axis, changes scale and rotates a bit for more user enjoyment
+
 ## v0.2.2 - 2021-02-03
 
 Minimum Lemmy version supported: `v0.9.4`

lib/pages/media_view.dart

@@ -1,8 +1,10 @@
+import 'dart:math' show max, min;
+
 import 'package:cached_network_image/cached_network_image.dart';
 import 'package:esys_flutter_share/esys_flutter_share.dart';
 import 'package:flutter/material.dart';
-import 'package:flutter/services.dart';
 import 'package:flutter_hooks/flutter_hooks.dart';
+import 'package:matrix4_transform/matrix4_transform.dart';
 import 'package:photo_view/photo_view.dart';
 
 import '../widgets/bottom_modal.dart';
@@ -11,6 +13,8 @@ import '../widgets/bottom_modal.dart';
 class MediaViewPage extends HookWidget {
   final String url;
   final GlobalKey<ScaffoldState> _key = GlobalKey();
+  static const yThreshold = 150;
+  static const speedThreshold = 45;
 
   MediaViewPage(this.url);
 
@@ -18,30 +22,19 @@ class MediaViewPage extends HookWidget {
   Widget build(BuildContext context) {
     final showButtons = useState(true);
     final isZoomedOut = useState(true);
+    final scaleIsInitial = useState(true);
+
+    final isDragging = useState(false);
+
+    final offset = useState(Offset.zero);
+    final prevOffset = usePrevious(offset.value);
 
     notImplemented() {
       _key.currentState.showSnackBar(const SnackBar(
           content: Text("this feature hasn't been implemented yet 😰")));
     }
 
-    useEffect(() {
+    // TODO: hide navbar and topbar on android without a content jump
-      if (showButtons.value) {
-        SystemChrome.setEnabledSystemUIOverlays([
-          SystemUiOverlay.bottom,
-          SystemUiOverlay.top,
-        ]);
-      } else {
-        SystemChrome.setEnabledSystemUIOverlays([]);
-      }
-      return null;
-    }, [showButtons.value]);
-
-    useEffect(
-        () => () => SystemChrome.setEnabledSystemUIOverlays([
-              SystemUiOverlay.bottom,
-              SystemUiOverlay.top,
-            ]),
-        []);
 
     share() {
       showModalBottomSheet(
@@ -77,6 +70,8 @@ class MediaViewPage extends HookWidget {
       key: _key,
       extendBodyBehindAppBar: true,
       extendBody: true,
+      backgroundColor:
+          Colors.black.withOpacity(max(0, 1.0 - (offset.value.dy.abs() / 200))),
       appBar: showButtons.value
           ? AppBar(
               backgroundColor: Colors.black38,
@@ -96,26 +91,67 @@ class MediaViewPage extends HookWidget {
               ],
             )
           : null,
-      body: GestureDetector(
+      body: Listener(
-        onTapUp: (details) => showButtons.value = !showButtons.value,
+        onPointerMove: scaleIsInitial.value
-        onVerticalDragEnd: isZoomedOut.value
+            ? (event) {
-            ? (details) {
+                if (!isDragging.value &&
-                if (details.primaryVelocity.abs() > 1000) {
+                    event.delta.dx.abs() > event.delta.dy.abs()) return;
+                isDragging.value = true;
+                offset.value += event.delta;
+              }
+            : (_) => isDragging.value = false,
+        onPointerCancel: (_) => offset.value = Offset.zero,
+        onPointerUp: isZoomedOut.value
+            ? (_) {
+                if (!isDragging.value) {
+                  showButtons.value = !showButtons.value;
+                  return;
+                }
+
+                isDragging.value = false;
+                final speed = (offset.value - prevOffset).distance;
+                if (speed > speedThreshold ||
+                    offset.value.dy.abs() > yThreshold) {
                   Navigator.of(context).pop();
+                } else {
+                  offset.value = Offset.zero;
                 }
               }
-            : null,
+            : (_) {
-        child: PhotoView(
+                offset.value = Offset.zero;
-          scaleStateChangedCallback: (value) {
+                isDragging.value = false;
-            isZoomedOut.value = value == PhotoViewScaleState.zoomedOut ||
+              },
-                value == PhotoViewScaleState.initial;
+        child: AnimatedContainer(
-          },
+          transform: Matrix4Transform()
-          minScale: PhotoViewComputedScale.contained,
+              .scale(max(0.9, 1 - offset.value.dy.abs() / 1000))
-          initialScale: PhotoViewComputedScale.contained,
+              .translateOffset(offset.value)
-          imageProvider: CachedNetworkImageProvider(url),
+              .rotate(min(-offset.value.dx / 2000, 0.1))
-          heroAttributes: PhotoViewHeroAttributes(tag: url),
+              .matrix4,
-          loadingBuilder: (context, event) =>
+          duration: isDragging.value
-              const Center(child: CircularProgressIndicator()),
+              ? Duration.zero
+              : const Duration(milliseconds: 200),
+          child: PhotoView(
+            backgroundDecoration:
+                const BoxDecoration(color: Colors.transparent),
+            scaleStateChangedCallback: (value) {
+              isZoomedOut.value = value == PhotoViewScaleState.zoomedOut ||
+                  value == PhotoViewScaleState.initial;
+              showButtons.value = isZoomedOut.value;
+
+              scaleIsInitial.value = value == PhotoViewScaleState.initial;
+              isDragging.value = false;
+              offset.value = Offset.zero;
+            },
+            onTapUp: isZoomedOut.value
+                ? null
+                : (_, __, ___) => showButtons.value = !showButtons.value,
+            minScale: PhotoViewComputedScale.contained,
+            initialScale: PhotoViewComputedScale.contained,
+            imageProvider: CachedNetworkImageProvider(url),
+            heroAttributes: PhotoViewHeroAttributes(tag: url),
+            loadingBuilder: (context, event) =>
+                const Center(child: CircularProgressIndicator()),
+          ),
         ),
       ),
     );

lib/util/goto.dart

@@ -67,6 +67,7 @@ void goToMedia(BuildContext context, String url) => Navigator.push(
       PageRouteBuilder(
         pageBuilder: (_, __, ___) => MediaViewPage(url),
         transitionDuration: const Duration(milliseconds: 300),
+        opaque: false,
         transitionsBuilder: (_, animation, __, child) =>
             FadeTransition(opacity: animation, child: child),
       ),

pubspec.lock

@@ -282,6 +282,13 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "0.12.10-nullsafety.1"
+  matrix4_transform:
+    dependency: "direct main"
+    description:
+      name: matrix4_transform
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.1.7"
   meta:
     dependency: transitive
     description:

pubspec.yaml

@@ -44,6 +44,8 @@ dependencies:
   timeago: ^2.0.27
   fuzzy: <1.0.0
   lemmy_api_client: ^0.10.2
+  matrix4_transform: ^1.1.7
+
 
   flutter:
     sdk: flutter