React Native Share Extension

This is a helper module which brings react native as an engine to drive share extension for your app.

Installation

installation should be very easy by just installing it from npm.

npm install react-native-share-extension --save

Setup

the setup requires a little bit more work. I will try to describe as detail as possible. I would love to use rnpm so I will welcome pull request.

iOS

• click on your project's name
• click on + sign

• select Share Extension under iOS > Application Extension

• select a name for your new share extension, in my case I chose MyShareEx

• delete both ShareViewController.h and ShareViewController.m. make sure to click on Move to Trash button during deletion.

• create new file under your share extension group. in my case it was MyShareEx

• make sure the type of that object is Objective-c File, e.g. for MyShareEx name it MyShareEx.m

• since we deleted ShareViewController.m, we need to tell the storyboard of your share extension where the view needs to be loaded. So click on MainInterface.storyboard and replace the class field from ShareViewController to whatever you chose above (in my case MyShareEx)

• now it's time to add our library. Right click on Libraries group and select Add Files to "Sample1"...

• select node_modules > react-native-share-extension > ios > ReactNativeShareExtension.xcodeproj

• now we need to tell the share extension that we want to read new header files. click on project name, in my case Sample1 then click on your extension name (in my case MyShareEx). After that click on Build Settings and search for Header Search Paths

• add the new path $(SRCROOT)/../node_modules/react-native-share-extension/ios with recursive selected.

• we need to add some flags as well, so search for Other Linker Flags and add -ObjC and -lc++

• we also need to add all the static libraries such as react and Share Extension. so select General tab and under Linked frameworks and Libraries click on + and add all of the selected static binaries there.

• we need to modify the Info.plist inside the extension (e.g. MyShareEx/Info.plist) to make sure that our share extension can connect to internet. This is useful if you need your share extension connects to your api server or react-native remote server dev. For doing that we need to App Transport Security Settings to Info.plist

• now go back to your extension file (in my case MyShareEx.m) and paste the following code there being sure to substitute MyShareEx in all three places for whatever you chose above

#import <Foundation/Foundation.h>
#import "ReactNativeShareExtension.h"
#import "React/RCTBundleURLProvider.h"
#import "React/RCTRootView.h"

@interface MyShareEx : ReactNativeShareExtension
@end

@implementation MyShareEx

RCT_EXPORT_MODULE();

- (UIView*) shareView {
  NSURL *jsCodeLocation;

  jsCodeLocation = [[RCTBundleURLProvider sharedSettings] jsBundleURLForBundleRoot:@"index.ios" fallbackResource:nil];

  RCTRootView *rootView = [[RCTRootView alloc] initWithBundleURL:jsCodeLocation
                                                      moduleName:@"MyShareEx"
                                               initialProperties:nil
                                                   launchOptions:nil];
  rootView.backgroundColor = nil;
  return rootView;
}

@end

• now try to build the project. it should build successfully.

Android

• edit android/settings.gradle file and add the following

include ':app', ':react-native-share-extension'

project(':react-native-share-extension').projectDir = new File(rootProject.projectDir, '../node_modules/react-native-share-extension/android')

• edit android/app/build.gradle and add the following line before react section in dependency

dependencies {
    ...
    compile project(':react-native-share-extension')
    compile "com.facebook.react:react-native:+"
}

• create a folder called share under your java project and create two files. Call them ShareActivity.java and ShareApplication.java....just like your main project.

• ShareActivity should look like this

// define your share project, if your main project is com.sample1, then com.sample1.share makes sense....
package com.sample1.share;


// import ReactActivity
import com.facebook.react.ReactActivity;


public class ShareActivity extends ReactActivity {
    @Override
    protected String getMainComponentName() {
      // this is the name AppRegistry will use to launch the Share View
        return "MyShareEx";
    }

}

• ShareApplication should look like this

// your package you defined in ShareActivity
package com.sample1.share;
// import build config
import com.sample1.BuildConfig;

import com.alinz.parkerdan.shareextension.SharePackage;

import android.app.Application;

import com.facebook.react.shell.MainReactPackage;
import com.facebook.react.ReactNativeHost;
import com.facebook.react.ReactApplication;
import com.facebook.react.ReactPackage;

import java.util.Arrays;
import java.util.List;


public class ShareApplication extends Application implements ReactApplication {
 private final ReactNativeHost mReactNativeHost = new ReactNativeHost(this) {
   @Override
   protected boolean getUseDeveloperSupport() {
     return BuildConfig.DEBUG;

   }

   @Override
   protected List<ReactPackage> getPackages() {
     return Arrays.<ReactPackage>asList(
         new MainReactPackage(),
         new SharePackage()
     );
   }
 };

 @Override
 public ReactNativeHost getReactNativeHost() {
     return mReactNativeHost;
 }
}

• MainApplication should look like this

// your package you defined in ShareActivity
package com.sample1;

import android.app.Application;
import android.util.Log;

import com.facebook.react.ReactApplication;
import com.facebook.react.ReactInstanceManager;
import com.facebook.react.ReactNativeHost;
import com.facebook.react.ReactPackage;
import com.facebook.react.shell.MainReactPackage;

import com.alinz.parkerdan.shareextension.SharePackage;

import java.util.Arrays;
import java.util.List;

public class MainApplication extends Application implements ReactApplication {

  private final ReactNativeHost mReactNativeHost = new ReactNativeHost(this) {
    @Override
    protected boolean getUseDeveloperSupport() {
      return BuildConfig.DEBUG;
    }

    @Override
    protected List<ReactPackage> getPackages() {
      return Arrays.<ReactPackage>asList(
          new MainReactPackage(),
          new SharePackage()
      );
    }
  };

  @Override
  public ReactNativeHost getReactNativeHost() {
      return mReactNativeHost;
  }
}

• edit android/app/src/main/AndroidMainfest.xml and add the new activity right after devSettingActivity.

<activity android:name="com.facebook.react.devsupport.DevSettingsActivity"/>

<activity
    android:noHistory="true"
    android:name=".share.ShareActivity"
    android:configChanges="orientation"
    android:label="@string/title_activity_share"
    android:screenOrientation="portrait"
    android:theme="@style/Theme.Share.Transparent" >
   <intent-filter>
     <action android:name="android.intent.action.SEND" />
     <category android:name="android.intent.category.DEFAULT" />
    //  for sharing links include
     <data android:mimeType="text/plain" />
    //  for sharing photos include
    <data android:mimeType="image/*" />
   </intent-filter>
</activity>

in this new activity I have used 2 variables @string/title_activity_share and @style/Theme.Share.Transparent. you can add those in res/values.

so in values/strings.xml

<resources>
    ...
    <string name="title_activity_share">MyShareEx</string>
</resources>

and in values/styles.xml

<resources>
    ...
    <style name="Share.Window" parent="android:Theme">
        <item name="android:windowEnterAnimation">@null</item>
        <item name="android:windowExitAnimation">@null</item>
    </style>

    <style name="Theme.Share.Transparent" parent="android:Theme">
        <item name="android:windowIsTranslucent">true</item>
        <item name="android:windowBackground">@android:color/transparent</item>
        <item name="android:windowContentOverlay">@null</item>
        <item name="android:windowNoTitle">true</item>
        <item name="android:windowIsFloating">true</item>
        <item name="android:backgroundDimEnabled">true</item>
        <item name="android:windowAnimationStyle">@style/Share.Window</item>
    </style>
</resources>

• now you should be able to compile the code without error.

if you need to add more packages to your share extension do not overrides getPackages. instead override getMorePackages method under ShareExActivity.

Share Component

so both share extension and main application are using the same code base, or same main.jsbundle file. So the trick to separate Share and Main App is registering 2 different Component entries with AppRegistry.registerComponent.

so in both iOS and android share extension we are telling react to load the extension component (in my case MyShareEx) from js.

so in index.ios.js and index.android.js we are writing the same code as

//index.android.js
import React from 'react'
import { AppRegistry } from 'react-native'

import App from './app.android'
import Share from './share.android'

AppRegistry.registerComponent('Sample1', () => App)
AppRegistry.registerComponent('MyShareEx', () => Share) // TODO: Replace MyShareEx with my extension name

//index.ios.js
import React from 'react'
import { AppRegistry } from 'react-native'

import App from './app.ios'
import Share from './share.ios'

AppRegistry.registerComponent('Sample1', () => App)
AppRegistry.registerComponent('MyShareEx', () => Share) // TODO: Replace MyShareEx with my extension name

so the app.ios and app.android.js refers to main app and share.ios.js and share.android.js refers to share extension.

Share Extension APIs

• data() is a function that returns a promise. Once the promise is resolved, you get two values, type and value.

import ShareExtension from 'react-native-share-extension'
...

const { type, value } = await ShareExtension.data()

• close()

it simply close the share extension and return the touch event back to application that triggers the share.

Test on Device without dev-server

because share extension in ios devices are separate containers and the do not have access to main app folder, you have to build the script twice and package it inside the share extension container. The easiest way of doing this is create a New Script Phase in Build Phases of your share extension and copy the following line

export NODE_BINARY=node
../node_modules/react-native/packager/react-native-xcode.sh

On iOS: Set the NSExtensionActivationRule key in your Info.plist

For the time being, this package only handles sharing of urls specifically from browsers. In order to tell the system to show your extension only when sharing a url, you must set the NSExtensionActivationRule key (under NSExtensionAttributes) in the share extension's Info.plist file as follows (this is also needed to pass Apple's reveiw):

<key>NSExtensionAttributes</key>
<dict>
  <key>NSExtensionActivationRule</key>
  <dict>
    <key>NSExtensionActivationSupportsWebURLWithMaxCount</key>
    <integer>1</integer>
  </dict>
</dict>

Note that while the above will prevent many apps from wrongly sharing using your extension, some apps (e.g., YouTube) will still allow sharing using your extension, which might cause your extension to crash. Check out this issue for details.

For reference about NSExtensionActivationRule checkout Apple's docs

Final note

I have used react-native-modalbox module to handle the showing and hiding share extension which makes the experience more enjoyable for the user.

Cheers