@jamsch/react-native-duo-drag-drop

@jamsch/react-native-duo-drag-drop

Duolingo-style drag and drop for React Native using react-native-gesture-handler & react-native-reanimated. This library is heavily inspired by the work done by William Candillon in his video: Duolingo Drag-and-drop - "Can it be done in React Native?"

Pre-requisites

Please make sure you have the the following dependencies installed in your project before continuing:

• react-native >= 0.64
• react-native-reanimated >= 2.2
• react-native-gesture-handler >= 1.10

Installation

npm install @jamsch/react-native-duo-drag-drop

Basic Usage

import { GestureHandlerRootView } from "react-native-gesture-handler";
import DuoDragDrop from "@jamsch/react-native-duo-drag-drop";

function App() {
  return (
    <GestureHandlerRootView style={{ flex: 1 }}>
      <View style={{ margin: 20 }}>
        <DuoDragDrop words={["Juan", "She", "apples", "today", "with", "eats", "her", "another"]} />
      </View>
    </GestureHandlerRootView>
  );
}

export default App;

DuoDragDrop props

Prop	Type	Description
words	string[]	List of words that will be used for the drag-and-drop
extraData	any?	(Optional) A marker property for telling the words to re-render
wordHeight	number?	(Optional) height of an individual word. Default: 45
wordGap	number?	(Optional) The gap between each word / line: Default: 4
wordBankOffsetY	number?	(Optional) The offset between the "Bank" pile and the "Answer" pile. Default: 20
wordBankAlignment	"center" | "right" | "left"	(Optional) Alignment of the words in the word bank. Default "center"
gesturesDisabled	boolean?	(Optional) Whether tap & drag gestures are disabled. Default: false
rtl	boolean?	(Optional) Whether to lay out words in the "Answer" pile from right-to-left (for languages such as Arabic)
renderWord	(word: string, index: number) => JSX.Element	(Optional) Overrides the default word renderer
renderPlaceholder	(props: {style: StyleProp<ViewStyle>}) => JSX.Element	(Optional) Overrides the default placeholder renderer
renderLines	(props: { numLines: number; containerHeight: number; lineHeight: number }) => JSX.Element	(Optional) Overrides the default lines renderer

Fetching words in the "bank" or "answered" pile

You can use refs to find whether words are in the "answered" pile or in the "bank".

As a reference, the "word bank" is the list of words at the bottom, and the "answered" words are the list of words the user has dragged up in to the lines.

import { GestureHandlerRootView } from "react-native-gesture-handler";
import DuoDragDrop, { DuoDragDropRef } from "@jamsch/react-native-duo-drag-drop";

function App() {
  const ref = useRef<DuoDragDropRef>(null);

  return (
    <GestureHandlerRootView style={{ flex: 1 }}>
      <View style={{ margin: 20, minHeight: 300 }}>
        <DuoDragDrop ref={ref} words={["Juan", "She", "apples", "today", "with", "eats", "her", "another"]} />
      </View>
      <Button
        title="Get words"
        onPress={() => {
          const answered = ref.current?.getAnsweredWords();
          console.log(answered); // ["Juan", "She"]
          const words = ref.current?.getWords();
          console.log(words); // { answered: ["Juan", "She"], bank: ["today", "with", ...] }
        }}
      />
    </GestureHandlerRootView>
  );
}

export default App;

Customising Words/Lines/Placeholders

You can either customise the default "Word"/"Lines"/"Placeholder" components or provide your own components. For example:

import DuoDragDrop, { Word, Lines, Placeholder } from "@jamsch/react-native-duo-drag-drop";

function DndExample() {
  return (
    <DuoDragDrop
      words={["Juan", "She", "apples", "today", "with", "eats", "her", "another"]}
      renderWord={(word, index) => (
        <Word
          containerStyle={{
            backgroundColor: "teal",
          }}
          textStyle={{
            color: index % 2 === 0 ? "white" : "black",
          }}
        />
      )}
      // Change the border radius of the default Placeholder
      renderPlaceholder={({ style }) => <Placeholder style={[style, { borderRadius: 5 }]} />}
      // Modify the container/line style of Lines.
      renderLines={(props) => (
        <Lines {...props} containerStyle={{ backgroundColor: "transparent" }} lineStyle={{ borderColor: "#CCC" }} />
      )}
    />
  );
}

Contributing

See the contributing guide to learn how to contribute to the repository and the development workflow.

License

MIT