Right-to-Left (RTL) Styling Best Practices

RTL (Right-to-Left) is a text direction that is used in languages such as Arabic, Hebrew, and Persian. In RTL languages, the text is written from right to left. When designing an app for RTL languages, it is important to consider the following best practices:

Styling Components for RTL and LTR Layouts

Certain UI elements need to be mirrored when switching between RTL and LTR. To handle this:

Direction-Aware Flexbox Layouts

Flexbox automatically handles direction-based layouts, but you should be mindful of flexDirection, alignItems, and justifyContent properties.

For example:

const styles = StyleSheet.create({
  container: {
    flexDirection: I18nManager.isRTL ? "row-reverse" : "row",
  },
});

Padding and Margin Adjustments

While setting padding and margin, use directional properties such as paddingStart, paddingEnd, marginStart, and marginEnd instead of absolute values like paddingLeft and paddingRight.

const styles = StyleSheet.create({
  container: {
    paddingStart: 10, // Automatically adjusts for RTL
    paddingEnd: 10,
  },
});

Text Alignment

For text alignment, use textAlign: 'auto' which automatically handles alignment based on the language direction. Alternatively:

textAlign: I18nManager.isRTL ? "right" : "left";

TextInput Component

For TextInput, RTL text should automatically be supported. However, you may need to handle placeholders and input text alignment:

<TextInput
  style={{ textAlign: I18nManager.isRTL ? "right" : "left" }}
  placeholder="Enter text"
/>

Also, consider setting textAlignVertical if the input spans multiple lines.

Horizontal Scrolling in RTL Mode

• By default, when FlatList is used with horizontal scrolling (horizontal={true}) and the app is in RTL mode, the list automatically starts from the right.

• The content will align accordingly, and the list scrolls from right to left, which is the expected behavior for RTL layouts.

• Inverting the Scroll Behavior:

  <FlatList
    horizontal={true}
    inverted={I18nManager.isRTL} // Inverts the scroll behavior
    data={data}
    renderItem={renderItem}
  />

Below is a detailed table of RTL-supported style properties in React Native. These properties automatically adjust their behavior based on the layout direction (LTR or RTL).

Icons and Images

When using icons and images, ensure that they are mirrored correctly for RTL layouts. Some icons and images might need to be mirrored in RTL mode. React Native supports this with the transform property:

<Image
  source={yourImageSource}
  style={{
    transform: [{ scaleX: I18nManager.isRTL ? -1 : 1 }],
  }}
/>

Table of RTL-Supported Styles

Style Property	Description	Equivalent LTR Property	Equivalent RTL Property
paddingStart	Sets padding at the leading edge (start) of the container. Adjusts based on layout direction (LTR/RTL).	paddingLeft	paddingRight
paddingEnd	Sets padding at the trailing edge (end) of the container. Adjusts based on layout direction (LTR/RTL).	paddingRight	paddingLeft
marginStart	Sets margin at the leading edge (start) of the container. Adjusts based on layout direction (LTR/RTL).	marginLeft	marginRight
marginEnd	Sets margin at the trailing edge (end) of the container. Adjusts based on layout direction (LTR/RTL).	marginRight	marginLeft
start	Sets position from the leading edge (start) for absolute/relative positioning. Adjusts based on layout direction (LTR/RTL).	left	right
end	Sets position from the trailing edge (end) for absolute/relative positioning. Adjusts based on layout direction (LTR/RTL).	right	left
textAlign	Adjusts text alignment based on the layout direction. Use 'auto' for automatic alignment based on LTR/RTL.	left, center, right	Same as LTR
flexDirection	Defines the primary axis of layout. Use 'row-reverse' for RTL-specific adjustments.	row, column	row-reverse, column
borderStartWidth	Sets border width at the leading edge (start) of the container. Adjusts based on layout direction (LTR/RTL).	borderLeftWidth	borderRightWidth
borderEndWidth	Sets border width at the trailing edge (end) of the container. Adjusts based on layout direction (LTR/RTL).	borderRightWidth	borderLeftWidth
borderStartColor	Sets border color at the leading edge (start) of the container. Adjusts based on layout direction (LTR/RTL).	borderLeftColor	borderRightColor
borderEndColor	Sets border color at the trailing edge (end) of the container. Adjusts based on layout direction (LTR/RTL).	borderRightColor	borderLeftColor

Key Notes:

1. Padding and Margin: paddingStart, paddingEnd, marginStart, and marginEnd adjust padding and margin relative to the layout direction (LTR or RTL).
2. Text Alignment: Use textAlign: 'auto' to automatically align text based on the current language direction.
3. Flexbox Layout: The flexDirection property handles row direction changes. Using row-reverse is particularly useful in RTL layouts.
4. Border and Positioning: Border and positional properties (like start, end, borderStartWidth, etc.) ensure correct positioning and borders in both LTR and RTL.

By leveraging these RTL-supported style properties, your React Native app can automatically handle both left-to-right and right-to-left languages without the need for hardcoding directional adjustments.