React-native: initialProperties in Android

[ilansas]

Hi,

I'm looking for passing initial props to JS via Java. This can be done easily in Objective-C with initialProperties like this :

RCTRootView *rootView = [[RCTRootView alloc] initWithBundleURL:jsCodeLocation
                                                      moduleName:@"myapp"
                                               initialProperties:initialProperties
                                                   launchOptions:launchOptions];

Where initialProperties is an NSDictionary which will be converted in JSON and available in JS via this.props.
So I'm looking firstly if this is possible in Android and if yes, does any examples or doc exists ? Thanks

[facebook-github-bot]

Hey ilansas, thanks for reporting this issue!

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[baoti]

reactRootView.startReactApplication(mReactInstanceManager, "UIExplorerApp", initialProperties)

[ilansas]

Great thanks a lot !

[lynndylanhurley]

@baoti or @ilansas - where exactly should reactRootView.startReactApplication go in my app?

[lynndylanhurley]

Found it. Override the getLaunchOptions method of MainActivity.java:

  @Override
  protected Bundle getLaunchOptions() {
    Bundle opts = new Bundle();
    opts.putBoolean("someValue", true);
    return opts;
  }

[skeyboy]

hi, howa can i pass Map in the getLaunchOptions funtion at the Android

[Thibaut-Fatus]

seems like this is deprecated in react-native > 0.34

https://github.com/facebook/react-native/pull/9320

But I'm on 0.30 and cannot get it to work

public class MainActivity extends ReactActivity {

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

    /**
     *
     * move to ReactActivityDelegate if react-native > 0.34
     * https://github.com/facebook/react-native/pull/9320
     */
    @Override
    protected @Nullable Bundle getLaunchOptions() {
      Bundle opts = new Bundle();
      opts.putString("HOSTNAME", "localhost");
      opts.putInt("PORT", 8000);
      opts.putBoolean("SECURE", false);
      return opts;
    }
}

[micheletedeschi]

getlauchOptions has been moved inside ReactActivityDelegate, now I use this code:

public class MainActivity extends ReactActivity {

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

    @Override
    protected ReactActivityDelegate createReactActivityDelegate() {
        return new ReactActivityDelegate(this, getMainComponentName()) {
            @Nullable
            @Override
            protected Bundle getLaunchOptions() {
                Bundle initialProps = new Bundle();
                initialProps.putString("SOME_VARIABLE_1", BuildConfig.SOME_VARIABLE_1);
                initialProps.putString("SOME_VARIABLE_2", "some variable 2 value");
                return initialProps;
            }
        };
    }
}

[pppluto]

@micheletedeschi got error said below, any help?

/Users/tongchepluto/Desktop/JM/yjsPro/android/app/src/main/java/com/yjspro/MainActivity.java:21: 错误: 找不到符号
            protected Bundle getLaunchOptions() {
                      ^
  符号: 类 Bundle
/Users/tongchepluto/Desktop/JM/yjsPro/android/app/src/main/java/com/yjspro/MainActivity.java:22: 错误: 找不到符号
                Bundle initialProps = new Bundle();
                ^
  符号: 类 Bundle
/Users/tongchepluto/Desktop/JM/yjsPro/android/app/src/main/java/com/yjspro/MainActivity.java:22: 错误: 找不到符号
                Bundle initialProps = new Bundle();
                                          ^
  符号: 类 Bundle
3 个错误

[pppluto]

ops, missing import android.os.Bundle; new at android ,thanks a lot 🍻
by the way still need import com.facebook.react.ReactActivityDelegate;

[luoyushouchai]

How can i pass a callback ??

[StevenTB]

Is there a proper/official method to update these initialProps ? Currently I implemented a native method to send an object when it has changed, but feel free to give me your tips !

[shashank090789]

@micheletedeschi How can I pass object as initial props?