react-native-ui-lib/typings/components/switch/index.js

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import React from "react";
import { StyleSheet, Animated } from "react-native";
import _ from "lodash";
import { BaseComponent } from "../../commons";
import TouchableOpacity from "../touchableOpacity";
import { Colors, BorderRadiuses } from "../../style";
const INNER_PADDING = 2;
const DEFAULT_WIDTH = 42;
const DEFAULT_HEIGHT = 24;
const DEFAULT_THUMB_SIZE = 20;
/**
 * Switch component for toggling boolean value related to some context
 */
class Switch extends BaseComponent {
    constructor() {
        super(...arguments);
        this.state = {
            thumbPosition: new Animated.Value(0)
        };
        this.onPress = () => {
            _.invoke(this.props, "onValueChange", !this.props.value);
            this.toggle(!this.props.value);
        };
    }
    generateStyles() {
        this.styles = createStyles(this.getThemeProps());
    }
    componentWillReceiveProps(nextProps) {
        if (this.props.value !== nextProps.value) {
            this.toggle(nextProps.value);
        }
    }
    toggle(value) {
        const { thumbPosition } = this.state;
        Animated.timing(thumbPosition, {
            toValue: value ? 1 : 0,
            duration: 100
        }).start();
    }
    calcThumbOnPosition() {
        const props = this.getThemeProps();
        const width = props.width || DEFAULT_WIDTH;
        const thumbSize = props.thumbSize || DEFAULT_THUMB_SIZE;
        const position = width - (2 * INNER_PADDING + thumbSize);
        return position;
    }
    renderThumb() {
        const { thumbStyle } = this.getThemeProps();
        const { thumbPosition } = this.state;
        const interpolatedTranslateX = thumbPosition.interpolate({
            inputRange: [0, 1],
            outputRange: [0, this.calcThumbOnPosition()]
        });
        const thumbPositionStyle = {
            transform: [{ translateX: interpolatedTranslateX }]
        };
        return (<Animated.View style={[this.styles.thumb, thumbPositionStyle, thumbStyle]}/>);
    }
    render() {
        const { value, style, testID } = this.getThemeProps();
        return (<TouchableOpacity activeOpacity={1} style={[
            this.styles.switch,
            value ? this.styles.switchOn : this.styles.switchOff,
            style
        ]} onPress={this.onPress} testID={testID}>
        {this.renderThumb()}
      </TouchableOpacity>);
    }
}
Switch.displayName = "Switch";
function createStyles({ width = DEFAULT_WIDTH, height = DEFAULT_HEIGHT, onColor = Colors.blue30, offColor = Colors.blue60, thumbColor = Colors.white, thumbSize = DEFAULT_THUMB_SIZE }) {
    return StyleSheet.create({
        switch: {
            width,
            height,
            borderRadius: BorderRadiuses.br100,
            justifyContent: "center",
            padding: INNER_PADDING
        },
        switchOn: {
            backgroundColor: onColor
        },
        switchOff: {
            backgroundColor: offColor
        },
        thumb: {
            width: thumbSize,
            height: thumbSize,
            borderRadius: thumbSize / 2,
            backgroundColor: thumbColor
        }
    });
}
export default Switch;