Customization

Congrats! You've installed React Native Elements and your immediate question goes something like this:

So umm, how I do change how it looks?

Great question! A UI Kit wouldn't be that useful if the apps everyone built looked the same right? For this case React Native Elements provide a number of props on each component to enable you to style them how you want.

Component Styles

Every component from React Native Elements has a container around it. The container is just a traditional <View /> from react native that has some styling on it. This default styling prevents components from colliding with each other. If you want to change how two components react to each on the screen your first stop should be the containerStyle prop.

Similar to containerStyle, components may provide their custom style props like buttonStyle, titleStyle etc. Always refer to the documentation for the component to find out which style props it provides.

Theming

While component styles are great for single use, you may want to have the same styling for every instance of a component. For example, you may want all your buttons to be blue or have the same font. Here are some ways to reuse styles with React Native Elements.

Using Composition

With this approach, we create one component with the styles we want and use that instead of the built-in component.

import React from 'react';
import { Button } from 'react-native-elements';

const RaisedButton = (props) => <Button raised {...props} />;

// Your App
const App = () => {
  return <RaisedButton title="Yea" />;
};

If we want to use a button that's raised in our app, we can use RaisedButton instead of using Button. This component still accepts all the props from the normal Button just that it has the raised prop set by default.

Using ThemeProvider

The previous solution works great for only one component, but imagine having to do this for every component you want custom styles for. That could get a bit tedious to manage. Thankfully, there's a better way to do this. React Native Elements ships with a 3 utilities for large-scale theming.

Firstly you'll want to set up your ThemeProvider.

import { ThemeProvider, Button } from 'react-native-elements';

const theme = {
  Button: {
    raised: true,
  },
};

// Your App
const App = () => {
  return (
    <ThemeProvider theme={theme}>
      <Button title="My Button" />
      <Button title="My 2nd Button" />
    </ThemeProvider>
  );
};

The example above achieves the same goals as the first example — apply the same styles to multiple instances of Button in the app. However this example applies the raised prop to every instance of Button inside the component tree under ThemeProvider. Both of these buttons will have the raised prop set to true.

This is extremely convenient and is made possible through React's Context API.

---

Order of Styles

What happens now if we want a Button that isn't raised? To do that we have to the understand the order in which styles are applied.

Internal > Theme > External

Internal

Internal components styles are the styles which are defined in the component file. These are applied first.

Theme

Theme styles are the values that are set by the ThemeProvider If present, these are applied second.

import { ThemeProvider, Button } from 'react-native-elements';

const theme = {
  Button: {
    titleStyle: {
      color: 'red',
    },
  },
};

const App = () => {
  return (
    <ThemeProvider theme={theme}>
      <Button title="My Button" />
    </ThemeProvider>
  );
};

This will override the white color for the title set in the component's style.

External

External styles are the styles which are set through the component props. These are applied last and have the highest precedence.

import { ThemeProvider, Button } from 'react-native-elements';

const theme = {
  Button: {
    titleStyle: {
      color: 'red',
    },
  },
};

const App = () => {
  return (
    <ThemeProvider theme={theme}>
      <Button title="My Button" titleStyle={{ color: 'pink' }} />
    </ThemeProvider>
  );
};

This will override both the white color for the title set in the component's style as well as the red color set in the theme.

Remember if you want to override the values set in the theme you can always use component props.

---

The Theme Object

By default, the theme object looks like this. You can add whatever values you want to the theme, and they will be merged with the default. By default the platform colors aren't used anywhere. These native colors are added for your convenience.

interface theme {
  colors: {
    primary;
    secondary;
    grey0;
    grey1;
    grey2;
    grey3;
    grey4;
    grey5;
    greyOutline;
    searchBg;
    success;
    error;
    warning;
    divider;
    platform: {
      ios: {
        primary;
        secondary;
        success;
        error;
        warning;
      };
      android: {
        // Same as ios
      };
    };
  };
}

Setting styles in the theme is as simple as using the name of the component, as a key and the props you want to change as the value.

import { ThemeProvider } from 'react-native-elements';

const theme = {
  Avatar: {
    rounded: true,
  },
  Badge: {
    textStyle: { fontSize: 30 },
  },
};

...

<ThemeProvider theme={theme}>

---

Using the theme in your own components

You may want to make use of the theming utilities in your own components. For this you can use the withTheme HOC exported from this library. It adds three props to the component it wraps - theme, updateTheme and replaceTheme.

import React from 'react';
import { Text } from 'react-native';
import { withTheme } from 'react-native-elements';

function MyComponent(props) {
  const { theme, updateTheme, replaceTheme } = props;
  return <Text style={{ color: theme.colors.primary }}>Yo!</Text>;
}

export default withTheme(MyComponent);

The updateTheme function merges the theme passed in with the current theme.

const theme = {
  colors: {
    primary: 'pink',
  },
};

// We can update the primary color
updateTheme({ colors: { primary: 'red' } });

The replaceTheme function merges the theme passed in with the default theme.

Don't want to wrap your components? You can use the ThemeConsumer component which uses render props!

import React from 'react';
import { Text } from 'react-native';
import { ThemeConsumer } from 'react-native-elements';

const MyComponent = () => (
  <ThemeConsumer>
    {({ theme }) => (
      <Text style={{ color: theme.colors.primary }}>Yo!</Text>;
    )}
  </ThemeConsumer>
)

You can also use the ThemeContext directly if you use hooks.

import React, { useContext } from 'react';
import { Text } from 'react-native';
import { ThemeContext } from 'react-native-elements';

const MyComponent = () => {
  const { theme } = useContext(ThemeContext);

  return (
    <View style={styles.container}>
      <Text style={{ color: theme.colors.primary }}>Yo!</Text>
    </View>
  );
};

---

Using the respective platform's native colors

You may want to style your app using the native color palette. You can do this using the colors object and the Platform API.

import { Platform } from 'react-native';
import { Button, colors, ThemeProvider } from 'react-native-elements';

const theme = {
  colors: {
    ...Platform.select({
      default: colors.platform.android,
      ios: colors.platform.ios,
    }),
  },
};

const App = () => {
  return (
    <ThemeProvider theme={theme}>
      // This button's color will now be the default iOS / Android blue.
      <Button title="My Button" />
    </ThemeProvider>
  );
};

---

Common Pitfalls

This section outlines some common pitfalls when using Theming.

My local styles aren't working with the theme

It's important to understand that the ThemeProvider works by merging your local(external) styles with those set on the theme. This means that in both cases the type of these styles must be the same.

Example 1

const theme = {
  Button: {
    containerStyle: {
      marginTop: 10;
    }
  }
}

<Button
  containerStyle={{ backgroundColor: 'blue' }}
/>

✅ Works

In both cases the style is an object

Example 2

const theme = {
  Button: {
    containerStyle: [
      {
        marginTop: 10;
      }
    ]
  }
}

<Button containerStyle={[{ backgroundColor: 'blue' }]} />

✅ Works

In both cases the style is an array

Example 3

const theme = {
  Button: {
    containerStyle: {
      marginTop: 10;
    }
  }
}

<Button containerStyle={[{ backgroundColor: 'blue' }]} />

🚫 Doesn't work

In one case the style is an object and another the style is an array