onReady in React Native

I just have a short question about onReady in React Native. I want to use it like this:

<View style={styles.main}><ReelSet ref={(ref) => {this.reelSet = ref;}} onReady={this.onReelsetReady} /></View>

ReelSet is my component. It doesn't come with React Native.

onReelsetReady looks like this:

onReelsetReady = () => {    this.setState({      spinButtonActive: true,      loadingVisible: false,    })    console.log("debug");  }

react-native info output:

    info Fetching system and libraries information...    System:        OS: Windows 10 10.0.18362        CPU: (8) x64 Intel(R) Core(TM) i7-6820HQ CPU @ 2.70GHz        Memory: 6.78 GB / 15.67 GB      Binaries:        Node: 12.9.1 - C:\Program Files\nodejs\node.EXE        npm: 6.10.2 - C:\Program Files\nodejs\npm.CMD      IDEs:        Android Studio: Version  3.5.0.0 AI-191.8026.42.35.5900203      npmPackages:        react: ~16.9.0 => 16.9.0        react-native: https://github.com/expo/reactnative/archive/sdk37.0.1.tar.gz => 0.61.4

expo --version

3.17.23

If there is any solution, I would be glad if someone could post it.