Does react native support base64 encoded images?

-

Does react native support base 64 encoded images?

I tried:

<Image source={{uri: 'data:image/png;base64,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'}} style={styles.image}/>

but it didn't work. Am I just doing is wrong or is it not supported?

I think Ramsay is wrong, react native have a fully support on base64 image. I found this

https://facebook.github.io/react-native/docs/tabbarios.html

this is a official example of how to create a iOS TabBarController, and they use a base64 image as one of the TabBar's icon.

I think you did not specify the width and the height in the style property of the <Image/>.

I tried to use your base64 image in my React Native Playground, and it works.

Usage

var base64Icon = 'data:image/png;base64,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';

and use in this way

<Image style={{width: 100, height: 50, resizeMode: Image.resizeMode.contain, borderWidth: 1, borderColor: 'red'}} source={{uri: base64Icon}}/>

I don't think this is supported. Unless the URL contains "http" or "https", it's considered a "static" image. Picking through the code, the instantiation of the final image boils down to:

if ([path isAbsolutePath]) {
  image = [UIImage imageWithContentsOfFile:path];
} else {
  image = [UIImage imageNamed:path];
  if (!image) {
    image = [UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:path ofType:nil]];
  }
}

Step by step:

  1. If the URL is an absolute path, load it as a file
  2. Else if the image is cached (imageNamed), load that
  3. Else if the image is a relative path, load it from the app bundle

Obviously none of that relates to base64. I've created a pull request for this feature which you can view here:

https://github.com/facebook/react-native/pull/576

Comments

Post a Comment

Popular posts from this blog

Meaning of `{}` for return expression

-
15 1 I found by accident that the following compiles: #include <string> #include <iostream> class A{ int i{}; std::string s{}; public: A(int _i, const std::string& _s) : i(_i), s(_s) { puts("Called A(int, const std::string)"); } }; A foo(int k, const char* cstr){ return {k, cstr}; // (*) } int main(){ auto a = foo(10, "Hi!"); return 0; } The line of interest is (*). I guess the function foo is equivalent to: A foo(int k, const char* str){ return A(k, cstr); } However, is there a special name for this mechanism in (*)? Or is it just the simple fact that the compiler knows which constructor to call due to the return type? ...
Read more

Get current scroll position of ScrollView in React Native

-
Is it possible to get the current scroll position, or the current page of a <ScrollView> component in React Native? So something like: <ScrollView horizontal={true} pagingEnabled={true} onScrollAnimationEnd={() => { // get this scrollview's current page or x/y scroll position }}> this.state.data.map(function(e, i) { <ImageCt key={i}></ImageCt> }) </ScrollView> Try. <ScrollView onScroll={this.handleScroll} /> And then: handleScroll: function(event: Object) { console.log(event.nativeEvent.contentOffset.y); }, Disclaimer: what follows is primarily the result of my own experimentation in React Native 0.50. The ScrollView documentation is currently missing a lot of the information covered below; for instance onScrollEndDrag is completely undocumented. Since everything here relies upon undocumented behaviour, I can unfortunately make no promises that this information will remain correct a ...
Read more

flutter websocket connection issue

-
I am trying to develop a flutter app which connects to the server and exchanges data using websocket. The server is in .Net Core and using Asp.Net Core Websockets to implement this functionality. The problem I am facing is, my flutter app is not able to connect to the server and throws following error. E/flutter (31498): [ERROR:topaz/lib/tonic/logging/dart_error.cc(16)] Unhandled exception: E/flutter (31498): WebSocketChannelException: WebSocketChannelException: WebSocketException: Connection to 'http://127.0.0.1/client#' was not upgraded to websocket E/flutter (31498): #0 new IOWebSocketChannel._withoutSocket.<anonymous closure> (package:web_socket_channel/io.dart:83:24) E/flutter (31498): #1 _invokeErrorHandler (dart:async/async_error.dart:13:29) E/flutter (31498): #2 _HandleErrorStream._handleError (dart:async/stream_pipe.dart:286:9) E/flutter (31498): #3 _ForwardingStreamSubscription._handleError (dart:async/stream_pipe.dart:168:13) E/flutter (3149...
Read more