CODEWITHSUNDEEP
javaandroidreact-nativeandroid-intentreact-native-navigation
Jared
Jared

Reputation: 2096

How can I send an event from MainActivity.java to Javascript in React Native?

Currently the following code does successfully get the text that is being shared to the app, but I am having trouble finding out how to send this event to the Javascript side. I tried creating a new NavigationReactGateway but my app just crashes. I'm new to Java so I don't even know if I did it properly.

public class MainActivity extends SplashActivity {

    /**
     * Returns the name of the main component registered from JavaScript.
     * This is used to schedule rendering of the component.
     */
    protected String getMainComponentName() {
        return "MyApplication";
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        Intent intent = getIntent();
        String action = intent.getAction();
        String type = intent.getType();

        if (Intent.ACTION_SEND.equals(action) && type != null) {
            if ("text/plain".equals(type)) {
                handleSendText(intent);
            }
        }
    }

    void handleSendText(Intent intent) {
        String sharedText = intent.getStringExtra(Intent.EXTRA_TEXT);

        if (sharedText != null) {
            // Send event to Javascript as "share" event
        }
    }
}

What is the correct way to send this event to Javascript?

The app has react-native-navigation and there are a lot of references to an event emitter, I'm just unsure how to get the react context to emit the event. If that makes any sense.

Upvotes: 2

Views: 2239

Answers (2)

Jared
Jared

Reputation: 2096

I was able to modify the handleSendText method to the following to send an event.

private void handleSendText(Intent intent) {
    String sharedText = intent.getStringExtra(Intent.EXTRA_TEXT);

    if (sharedText != null) {
        ReactContext context = NavigationApplication.instance.getReactGateway().getReactContext();

        if (context != null) {
            WritableMap params = Arguments.createMap();
            params.putString("event", sharedText);

            context.getJSModule(DeviceEventManagerModule.RCTDeviceEventEmitter.class)
                .emit("share", params);
        }
    }
}

I also had to change from using the onCreate method to using onStop, then the react context has been initialized and my event launches whether the app was already open or not.

Upvotes: 2

Mayank Kumar Chaudhari
Mayank Kumar Chaudhari

Reputation: 18538

You can use webView.addJavascriptInterface()

You can find documentation here.

Upvotes: 0

Related Questions