TypeScript and React Native: Are the type definitions for RN styles wrong?

Question

I thought in React it is allowed to assign arrays to styles?

Like this:

import React from 'react';
import { Text } from "react-native";

// ...

render() {
  const textStyles = [styles.text];
  return <Text style={textStyles}>Some Text</Text>;
}

But TSLint complains about this line with:

[ts]
Type 'RegisteredStyle<{ color: string; fontWeight: string; fontSize?: undefined; padding: number; textAlign: "center"; } | { color: string; fontSize: number; fontWeight?: undefined; padding: number; textAlign: "center"; }>[]' is not assignable to type 'StyleProp<TextStyle>'.
  Type 'RegisteredStyle<{ color: string; fontWeight: string; fontSize?: undefined; padding: number; textAlign: "center"; } | { color: string; fontSize: number; fontWeight?: undefined; padding: number; textAlign: "center"; }>[]' is not assignable to type 'RecursiveArray<false | TextStyle | RegisteredStyle<TextStyle> | null | undefined>'.
Types of property 'pop' are incompatible.
  Type '() => RegisteredStyle<{ color: string; fontWeight: string; fontSize?: undefined; padding: number; textAlign: "center"; } | { color: string; fontSize: number; fontWeight?: undefined; padding: number; textAlign: "center"; }> | undefined' is not assignable to type '() => StyleProp<TextStyle>'.
    Type 'RegisteredStyle<{ color: string; fontWeight: string; fontSize?: undefined; padding: number; textAlign: "center"; } | { color: string; fontSize: number; fontWeight?: undefined; padding: number; textAlign: "center"; }> | undefined' is not assignable to type 'StyleProp<TextStyle>'.
      Type 'RegisteredStyle<{ color: string; fontWeight: string; fontSize?: undefined; padding: number; textAlign: "center"; } | { color: string; fontSize: number; fontWeight?: undefined; padding: number; textAlign: "center"; }> | undefined' is not assignable to type 'StyleProp<TextStyle>'.
      Type 'RegisteredStyle<{ color: string; fontWeight: string; fontSize?: undefined; padding: number; textAlign: "center"; } | { color: string; fontSize: number; fontWeight?: undefined; padding: number; textAlign: "center"; }>' is not assignable to type 'StyleProp<TextStyle>'.

What is going on here? Are the types of React Native wrong? Or am I somehow supposed to typecast these arrays for RN styles?

Answer 1

You can test some of ways for solve your problem, hope this work:

1 : style={styles.yourStyle as any} maybe you should do the trick!

2 : I can't see how you implement your styles but you can test something like this?

import { StyleSheet, TextStyle, ViewStyle } from "react-native";

type Style = {
    container: ViewStyle;
    title: TextStyle;
    icon: ImageStyle;
};

export default StyleSheet.create<Style>({
    container: {
        flex: 1
    },
    title: {
        color: red
    },
    icon: {
        width: 10,
        height: 10
    }
});