Butter Smooth Scrolling Animations in React Native – NativeBase.io Blog

  • Using Native Driver for AnimationsWhen working with animations in React Native, it is easy to run into performance issues, especially if your app involves complex animations.The Animated API was designed with a very important constraint in mind: it is serialisable.
  • This means we can send everything about the animation to the native layer before it has even started and allows native code to perform the animation on the UI thread without having to go through the bridge on every frame.Now we are talking!It is very useful because once the animation has started, the JS thread can be blocked and the animation will still run smoothly.When creating an Animation in React Native, you could create an Animated.Value and change this value to update some transforms in your UI components.
  • Or you may also update an Animated value by connecting it to an event of a View using Animated.event.However, most of the work happens on the JavaScript thread.
  • If it is blocked, the animation will skip frames.
  • It also needs to go from the JavaScript to Native layer on every frame to update native views.What the native driver does is move all of these steps to native.Since Animated produces a graph of animated nodes, it can be serialized and sent to native only once when the animation starts, eliminating the need to callback into the JS thread; the native code can take care of updating the views directly on the UI thread on every frame.How to embed this native driver in your app is covered in the coming section.

Jasbir singh has been working on creating smooth animation effects that are hooked up to scroll events in React Native. Here is a brief explanation from Jasbir on it. This article shares some of the…
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React Native and ReactJS – Ahmed Mahmoud – Medium

React Native and ReactJS  #react #frontenddevelopment #webdevelopment #reactjs #reactjs

  • React Native and ReactJSThey’re not quite the sameReact Native is a framework that lets you build mobile apps for different platforms using only javascript, even few contributors customized it to build desktop apps (Mac and Windows).
  • It’s quite similar to ReactJS in a way, however there are some differences between React Native and ReactJS.Is a framework:React Native is a framework, but ReactJS is a JS library.
  • Meaning, for ReactJS you’ll need a bundler like webpack and then you’ll figure out which modules you’ll need for the project, on the other hand, you won’t need any bundler or any other tools to bootstrap your project, only react-native-cli.
  • Doesn’t have HTML:In React Native, you won’t have html elements, you’ll have instead alternative components that work in a similar way, and they map to actual IOS and Android UI components that renders on the app.Because you’re not rendering HTML, you can’t use any ReactJS library that renders HTML, but you most probably will find alternative React Native libraries here.CSS only in JS:In React Native, styling is only done in JS, and it’s not exactly CSS, and it doesn’t always behave like it, nevertheless it looks pretty much like CSS.No CSS Animations:In React Native, you don’t have CSS Animations, the recommended way to animate a component is using Animated API.Developer tools for Code, not for UI:You still can use the same Chrome DevTools to debug your app, also you can use Redux DevTools to inspect the state of your app, but still you can’t inspect the UI with Chrome DevTools, you’ll have to use the platform native inspector (XCode/Android studio).
  • Tools:XCode (for IOS)Andriod Studio (for Andriod)Device (if you don’t want to run the app only on simulators)Here’s a React Native crash course that’ll help you get started really quickly.

React Native is a framework that lets you build mobile apps for different platforms using only javascript, even few contributors customized it to build desktop apps (Mac and Windows). It’s been…
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Experiments with High Performance Animation in React Native

Three major methods for shape animation with React Native via @salesforceeng

  • This story is my experience and experiments to achieve high performance animation in React Native.Along the way I learned tons from these blogs and recommend you read them as you dive deeper into building your own animations in React Native:React Native Animations Using Animated API from Nader DabitReact Native ART and D3 from Harry WolffBefore we continue, I would like to define what “high performance animation” in terms of my project.
  • Note: There is another OpenGL binding for React Native which enables a more flexible OpenGL implementation without the interface.Animation in React NativeIn my exploration I tested three major methods (with some variations) for doing shape animation with React Native.
  • For example, if we have a shape with a 1px border, it cannot be transformed to have a larger width/height and retain the same border width without redrawing.Experiments and ResultsRequest Animation Frame + JavaScript tweeningThe first approach is to change nothing but use the same code from the web implementation — meaning everything is done in JavaScript without any help from React Native.
  • The gaps between each country will also get scaled so the transformed shapes are not the same as the new shapes.Zoom animation with fade in/outThis method has a significant impact on the memory footprint since there are two views with a shadow node per shape.Animated + Hybrid Native Driver + Animated Shape (ART)For this approach I still used the Native Driver while I found there is a trick to communicate between the JS thread and UI thread using setNativeProps.
  • I first tried with React Native ART and switched to React Native SVG while both give similar results.Animated + Hybrid Native Driver + Animated Shape (OpenGL)After realizing the bottleneck comes from re-drawing shapes, I switched to another library which has the drawing logic implemented in OpenGL.

Archiving decent animation performance is quite tricky. This story is my experience and experiments to achieve high performance animation in React Native.
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React Native animations revisited — Part III – Blog @ Callstack.io

  • I hope that makes all the stuff related to animations a bit easier for you.
  • If we want to respond to screen gestures, and apply some animation as well (ie.
  • Now we only need to clear responder when unmounting component, and attach animation styles (which we already know!
  • First two functions are just used to ask to be responder, onPanResponderGrant() is invoked when responder is granted to our component, onPanResponderMove() is called every time component moves, and in onPanResponderRelease() you can tell what to do after finger is released.
  • React Native animations revisited – Part III

Animations are really important part of modern applications. But sometimes animation is not enough. If we want to respond to screen gestures, and apply some animation as well (ie. create drag and…
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React Native Animations Using the Animated API – React Native Training – Medium

#ReactNative Animations Using the Animated #API:  by @dabit3 #JavaScript #iOS #Android

  • We render a main View with three Animated.
  • Is the final code for this animation with a working example.
  • If the animation is done because it finished running normally, the completion callback will be invoked with {finished: true}, but if the animation is done because stop was called on it before it could finish (e.g. because it was interrupted by a gesture or another animation), then it will receive {finished: false}.
  • In the animate method, we set the values of all three animated values back to zero.
  • Animated.sequence() – Starts an array of animations in order, waiting for each to complete before starting the next.

We will be covering Animated.timing() and Animated.spring() as they are the most useful in my experience. Along with these three Animated methods, there are three ways to call these animations along…
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React Native Silicon Valley Meetup at Groupon – ReactJS News

New #no React Native Silicon Valley Meetup at Groupon  via @decoapp #Building

  • We will discuss the shortcuts and limitations of this approach to navigation.
  • Then we will dive into the new Navigation API for React Native, and demonstrate how we can customize the gestures and animations of navigation in our app.
  • Navigation in a mobile app is not typically as simple as navigation in the browser.
  • Food & Drinks Provided Provided 7:00pm – 7:30pm: Arrivals & Introductions 7:30pm – 8:00pm: 1.
  • Animating Navigation: Going off the deep end

Food & Drinks Provided Provided
7:00pm – 7:30pm: Arrivals & Introductions 7:30pm – 8:00pm: 1.  Featured Talk 8:00pm – 8:30pm: 2. Featured Talk 8:30pm – 9:15pm: Mingle
Eric Vicenti, @EricVicent @decoapp: Unraveling Navigation with @skevy. Meet him at the upcoming #reactnative meetup. Details:

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react-native-maps – ReactJS News – ReactJS News

#support react-native-maps – ReactJS News  #Component via @ReactJS_News #UI

  • Marker views can use the animated API to enhance the effect.
  • Callouts to markers can be completely arbitrary react views, similar to markers.
  • Issue: Since android needs to render its marker views as a bitmap, the animations APIs may not be compatible with the Marker views.
  • They can be interacted with like any other view.
  • Default markers will be rendered unless a custom marker is specified.

React Native Mapview component for iOS + Android @spikebrehm: Just published `react-native-maps@0.8.0`, with React Native 0.32.0 support and many bug fixes. Check it out!
@ReactJS_News: RT @spikebrehm react-native-maps #Component

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