MARS

Multi-Axis Reanimated Swipeable

A swipeable component with underlay for React Native.

Fully native interactions powered by Reanimated and React Native Gesture Handler

Derived from React Native Swipeable Item

Compatible with React Native Draggable FlatList

Install

1. Follow installation instructions for reanimated and react-native-gesture-handler
2. npm install or yarn add @onerouter/mars
3. import Swipeable from '@onerouter/mars'

Props

NOTE: Naming is hard. When you swipe right, you reveal the item on the left. With the vertical prop enabled, when you swipe up, you reveal the item on the bottom, and when you swipe down, you reveal the item on the top. So what do you name these things? I have decided to name everything according to swipe direction, but from a scroll position perspective (with "natural scrolling") - think of how you would swipe in a "viewpager"-style component. Therefore, a swipe left (or up if orientation is vertical) reveals the renderUnderlayNext component, right (or down if vertical) reveals the renderUnderlayPrevious component. Not perfect but it works.

NOTE: next and previous are reversed (next = right and previous = left) when horizontal (vertical prop not set to true) and in an RTL layout.

| Name | Type | Description | | :----------------------- | :---------------------------------------------------------------------- | :----------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | renderUnderlayNext | RenderUnderlay | Component to be rendered underneath row on left/top swipe. | | renderUnderlayPrevious | RenderUnderlay | Component to be rendered underneath row on right/bottom swipe. | | snapPointsNext | number[] | Pixel values left-(/top-)swipe snaps to (eg. [100, 300]) | | snapPointsPrevious | number[] | Pixel values right-(/bottom-)swipe snaps to (eg. [100, 300]) | | renderOverlay | RenderOverlay | Component to be rendered on above underlays. Use if you need access to programmatic open/close methods. May alternately pass children to Swipeable. | | onChange | (params: { openDirection: OpenDirection, snapPoint: number }) => void | Called when row is opened or closed. | | swipeEnabled | boolean | Enable/disable swipe. Defaults to true. | | activationThreshold | number | Distance finger must travel before swipe engages. Defaults to 20. | | swipeDamping | number | How much swipe velocity determines snap position. A smaller number means swipe velocity will have a larger effect and row will swipe open more easily. Defaults to 10. |

Hooks

| Name | Type | Description | | :------------------- | :--------------------------------------------------------------------------------------------- | :------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | useSwipeableParams | () => OverlayParams<T> & { open: OpenPromiseFn, percentOpen: Animated.DerivedValue<number> } | Utility hook that returns the same params as the render functions are called with. open() and percentOpen params reflect the context in which the hook is called (i.e. within an underlay or overlay component). | | |

function MyUnderlayComponent() {
  // Underlay components "know" which direction to open, so we don't need to call `openNext()` or `openPrevious()`, we can just call 'open()'
  // Underlay components also receive the `percentOpen` value of their own direction (`percentOpenNext` or `percentOpenPrevious`)
  const swipeableParams = useSwipeableParams();
  return <TouchableOpacity onPress={swipeableParams.open} />;
}

function MyOverlayComponent() {
  // Overlay components get the same params, but have defaults filled in for `open()` and `percentOpen` params.
  const swipeableParams = useSwipeableParams();
  return <TouchableOpacity onPress={swipeableParams.openNext} />;
}

Instance Methods

| Name | Type | Description | | :------ | :--------------------------------------------------------------------------------------------------------------------- | :---------------------------------------------------------------------- | | open | (OpenDirection.NEXT \| OpenDirection.PREVIOUS, snapIndex?: number, options?: { animated: boolean }) => Promise<void> | Imperatively open left/top or right/bottom. Promise resolves once open. | | close | (options?: { animated?: boolean}) => Promise<void> | Close all. Promise resolves once closed. |

// Imperative open example
const itemRef = useRef<SwipeableImperativeRef>(null)

...

<Swipeable ref={itemRef} />

...
itemRef.current?.open(OpenDirection.NEXT)

Types

type OpenCloseOptions = { animated?: boolean };
export type OpenPromiseFn = (
  snapPoint?: number,
  options?: OpenCloseOptions
) => Promise<void>;
export type ClosePromiseFn = (options?: OpenCloseOptions) => Promise<void>;

export type UnderlayParams<T> = {
  item: T;
  open: OpenPromiseFn;
  close: ClosePromiseFn;
  percentOpen: Animated.DerivedValue<number>;
  isGestureActive: Animated.DerivedValue<boolean>;
  direction: OpenDirection;
};

export type OverlayParams<T> = {
  item: T;
  openNext: OpenPromiseFn;
  openPrevious: OpenPromiseFn;
  close: ClosePromiseFn;
  openDirection: OpenDirection;
  percentOpenNext: Animated.DerivedValue<number>;
  percentOpenPrevious: Animated.DerivedValue<number>;
};

Notes

Gesture handlers can sometimes capture a gesture unintentionally. If you are using it with react-native-draggable-flatlist and the list is periodically not scrolling, try adding a small activationDistance (see the "Advanced" screen in the example snack).

Example

https://snack.expo.io/@computerjazz/swipeable-item

import { useCallback } from "react";
import {
  Text,
  View,
  StyleSheet,
  TouchableOpacity,
  FlatList,
  ListRenderItem,
} from "react-native";
import Swipeable, { useSwipeableParams } from "@onerouter/mars";

const NUM_ITEMS = 10;

function SimpleExample() {
  const renderItem: ListRenderItem<Item> = useCallback(({ item }) => {
    return (
      <Swipeable
        key={item.key}
        item={item}
        renderUnderlayNext={() => <UnderlayNext />}
        snapPointsNext={[150]}
      >
        <View
          style={[
            styles.row,
            { backgroundColor: item.backgroundColor, height: 100 },
          ]}
        >
          <Text style={styles.text}>{`${item.text}`}</Text>
        </View>
      </Swipeable>
    );
  }, []);

  return (
    <View style={styles.container}>
      <FlatList
        keyExtractor={(item) => item.key}
        data={initialData}
        renderItem={renderItem}
      />
    </View>
  );
}

export default SimpleExample;

const UnderlayNext = () => {
  const { close } = useSwipeableParams<Item>();
  return (
    <View style={[styles.row, styles.underlayNext]}>
      <TouchableOpacity onPress={() => close()}>
        <Text style={styles.text}>CLOSE</Text>
      </TouchableOpacity>
    </View>
  );
};

type Item = {
  key: string;
  text: string;
  backgroundColor: string;
};

function getColor(i: number) {
  const multiplier = 255 / (NUM_ITEMS - 1);
  const colorVal = i * multiplier;
  return `rgb(${colorVal}, ${Math.abs(128 - colorVal)}, ${255 - colorVal})`;
}

const initialData: Item[] = [...Array(NUM_ITEMS)].fill(0).map((d, index) => {
  const backgroundColor = getColor(index);
  return {
    text: `${index}`,
    key: `key-${backgroundColor}`,
    backgroundColor,
  };
});

const styles = StyleSheet.create({
  container: {
    flex: 1,
  },
  row: {
    flexDirection: "row",
    flex: 1,
    alignItems: "center",
    justifyContent: "center",
    padding: 15,
  },
  text: {
    fontWeight: "bold",
    color: "white",
    fontSize: 32,
  },
  underlayNext: {
    flex: 1,
    backgroundColor: "tomato",
    justifyContent: "flex-end",
  },
});