Flutter: implement material design Parent-child transitions (using SizeTransition?) - flutter

Using Flutter, I'd like to create a transition like the one in the material design Parent-child transitions here.
The transition should be from a child-widget in a SliverList to a new screen and vice-versa.
How can this be achieved?
Using a PageRouteBuilder and a one of the Animated Widgets maybe?

Related

Flutter CustomPainter paint behavoir and performance

I am learning and playing around with Flutter. Currently I am trying to reproduce an app I previously made with C# and WPF. In my Flutter app I have a list of Widgets extending CustomPainter. Now I am able to move/drag any of these widgets around the screen. What I see is that always when dragging one of this widgets all CustomPaint widgets are repainted. I checked what would happen if I decide to resize my window, and you can guess, all CustomPaint widgets are repainted.
I decided to create three different projects. One is using statefull widgets and setState to manage the state. The other is using Provider and the last one is using Riverpod. Still all Widgets extending CustomPainter are repainted when dragging a single Widget or resizing the window.
Now my question is, am I doing something wrong in my state management or is this behavior by default?
Also my C#/WPF app uses half the cpu the Flutter app uses when dragging one shape around. I did not expect such a difference. For now I did not make any complex CustomPaint obecjt in my flutter app. But should I expect a big performance reduction if I have many complex CustomPaint widgets?
am I doing something wrong in my state management or is this behavior
by default?
Yes and no. Widgets are rebuilt when the screen size changes, but dragging a widget should not make other widgets rebuild. You can try RepaintBoundary (https://api.flutter.dev/flutter/widgets/RepaintBoundary-class.html)
Should I expect a big performance reduction if I have many complex
CustomPaint widgets?
This has a lot to do with what kind of CustomPaint widgets you will be using and what is "many". You can test how long the CustomPaint widget's paint method takes, for example by using the profiler (https://docs.flutter.dev/perf/ui-performance). My assumption is that the efficiency decreases linearly as you add more CustomPaint widgets

Flutter: Achieving custom page swipe animation with pageview

I'm trying to make a custom animation for pageview and was looking for some guidance.
I already tried using transformer pageview but in my use case it's crashing and found it unreliable.
I'm looking to implement 2 animations
depth based transition where a pages move behind and scale back
regular overlay, during swipe pages are stacked on top of each other
I want to know if it's possible to achieve this with regular pageview, if so how do I go about it?
Appreciate your help

How to make scroll animations with flutter

How can I make scroll animations in flutter. Here is an example of what I want to create: https://www.apple.com/macbook-air-m2/. As you can see, when you scroll downwards the page is animated very nicely. I would like to create this sort of thing in flutter. Please specify if something like this will not work on any of flutters platforms.

how to create a scrollView in Flutter Flame

I need a listView for my Game. Is there a simple way to create one? There are no tutorials for such a feature and I couldn't find anything in the documentation.
Flame doesn't provide their own widgets for these things, we rely on Flutters excellent widget system.
So you create the widget directly in Flutter and then you either put your GameWidget in a stack (or similar) and use Flutter's own Navigation to move between the widgets, or you use Flame's overlay system.
For using the overlays you add the overlays that you want to have accessible when you create the GameWidget and then you call game.overlays.add to render a specific widget, and game.overlays.remove to stop rendering it.

How to animate fullscreen photo transition on swipe, like in Telegram?

When you swipe vertically, image is dragged towards the swipe, with fading out animation of black background.
And after release, it smoothly returns to it's previous position on the screen, like Hero animation does.
How is it possible to recreate such an effect using Flutter? The same scenario, in fullscreen photo view.
photo_view package is desired for fullscreen, so it shouldn't interfere with zooming.
What you need is actually an out-of-the-box widget, and it's surprisingly easy to use. It's called Hero. Basically, you wrap the widget you want to animate like that in a Hero widget, with a specific tag string, and, when you navigate to another screen, you wrap the destination widget in another Hero with the same tag. An effect like the one you shared can be achieved by wrapping two widgets with the same photo with Heroes in different PageRoutes.
Check out this Flutter widget of the week video to get you started, and this Flutter.dev article for a more detailed explanation on Hero widgets.
Edit: I see you are looking for a more specific image-viewer behavior. Then, I suggest you use the photo_view package, which includes many functionalities to visualize images, including the hero transition with swipe-dow-to-dismiss behaviors, pinching to zoom, etc.
I found the solution.
To create such an animation, you should use extended_image package, which has SlideOutPage widget for creation of such transitions.