I want to somehow visualize jest tests written with react-native-testing-library, by trying to actually render the rendered component on a real ios simulator. I am tying to think of a ways to do it. I guess it's somewhat like ssr for react native (the component is rendered in the jest process, and need to be sent to the device somehow), but I couldn't find any ways to achieve it.
Is there a way to somehow send the rendered component to the device?
I tried with react-serialize but it didn't work.
Any suggestions?
I want to know which is the best way to send and receive events only within the JS stack. The event which is being emitted should not reach the react-native bridge or simply I don't want the event to reach the android/iOS stack.
I know using NativeEventEmitter, we can send and receive event inside JS stack, but unsure whether this will pass the data through react native bridge. I want a optimised way of sending and receiving events within the JS stack.
Please help me find the right approach.
Thanks.
I'm trying to understand how I can do a signature capture in React Native. My App is created with create-react-native-app and Expo and I'd prefer to not have to eject the app to get this functionality to work.
Would it be possible to wrap something like this in a webview? https://github.com/szimek/signature_pad
I've also looked at this project, https://github.com/RepairShopr/react-native-signature-capture but it requires me to eject the app and use react-native link.
Looking for any advice or suggestions on how to implement this feature while keeping my project as straightforward as possible (ideally, using create-react-native-app, but if this isn't possible could someone please explain to me why?)
The way React Native works is that each component available in React Native maps to a native component in the underlying platform.
ie. a <Image /> is an ImageView in Android and a UIImageView.h in iOS.
The Javascript code itself runs in a Javascript thread on each platform and as you use Components in React Native, there's a translation layer that passes information from JS into the React Native bridge that then results in corresponding native components being created.
By default, React Native has included the following components: https://facebook.github.io/react-native/docs/components-and-apis.html#basic-components which means that only those components come out-of-the-box in React Native. If you want other components, then you have 2 options, either create a "composite" component in which your JS component is written into other JS components or, if your feature needs a native component not yet exposed by React Native, write your own "native" component to expose certain native functionality to your React Native code.
The way Expo works is that they have wrapped React Native and a handful of 3rd party components and built it within their application. The reason why you can't use a 3rd party native component they don't support is because when that component is used, the app itself doesn't have translation code to go from JS to a native Android/iOS view.
So, to do what you're asking, you'd need to find either a "native" drawing component that Expo has included in their platform/app. OR you need to find a "composite" drawing component that is built with other default React Native components (or other components Expo supports).
ie. On Android, I might build this with a Canvas view, but from what I can tell React Native doesn't support that object natively, so I would probably write this myself, etc.
It's hard for Expo to support every 3rd party "native" component out there because React Native is open source and it iterates so fast that most community-built components aren't always up to date or they might conflict with one another.
I am using react-native-signature-capture.
Working properly on both Android and iOS.
I know it's been a while, but there is an interesting article here: https://blog.expo.io/drawing-signatures-with-expo-25d1629ca1ac
Wait, but how?
Using “expo-pixi”, you can add a component that lets you choose your brush’s color, thickness, and opacity. Then when your user lifts her finger, you get a callback. From there you can take a screenshot of the transparent view or get the raw point data if that’s what you’re looking for.
I'm using react native for an sdk. I need to be able to send an event from JavaScript to the native layer when a particular action has occurred.
The docs mention that it's possible to send events to JS, but I need to be able to send events in the other direction.
Any ideas?
Is it possible to pass a javascript function from React Native onto iOS Native components such as a UIButton and execute there?
It is possible, but using events and not by sending JS to native components. Check out react-native docs for detailed information, but generally:
React Native enables you to perform cross-language function calls. You
can execute custom native code from JS and vice versa. Unfortunately,
depending on the side we are working on, we achieve the same goal in
different ways. For native - we use events mechanism to schedule an
execution of a handler function in JS, while for React Native we
directly call methods exported by native modules.