bsky-app/src/view/com/pager/TabBar.tsx
2024-02-27 03:56:25 +00:00

140 lines
3.8 KiB
TypeScript

import React, {useRef, useMemo, useEffect, useState, useCallback} from 'react'
import {StyleSheet, View, ScrollView, LayoutChangeEvent} from 'react-native'
import {Text} from '../util/text/Text'
import {PressableWithHover} from '../util/PressableWithHover'
import {usePalette} from 'lib/hooks/usePalette'
import {useWebMediaQueries} from 'lib/hooks/useWebMediaQueries'
import {DraggableScrollView} from './DraggableScrollView'
export interface TabBarProps {
testID?: string
selectedPage: number
items: string[]
indicatorColor?: string
onSelect?: (index: number) => void
onPressSelected?: (index: number) => void
}
export function TabBar({
testID,
selectedPage,
items,
indicatorColor,
onSelect,
onPressSelected,
}: TabBarProps) {
const pal = usePalette('default')
const scrollElRef = useRef<ScrollView>(null)
const [itemXs, setItemXs] = useState<number[]>([])
const indicatorStyle = useMemo(
() => ({borderBottomColor: indicatorColor || pal.colors.link}),
[indicatorColor, pal],
)
const {isDesktop, isTablet} = useWebMediaQueries()
const styles = isDesktop || isTablet ? desktopStyles : mobileStyles
// scrolls to the selected item when the page changes
useEffect(() => {
scrollElRef.current?.scrollTo({
x:
(itemXs[selectedPage] || 0) - styles.contentContainer.paddingHorizontal,
})
}, [scrollElRef, itemXs, selectedPage, styles])
const onPressItem = useCallback(
(index: number) => {
onSelect?.(index)
if (index === selectedPage) {
onPressSelected?.(index)
}
},
[onSelect, selectedPage, onPressSelected],
)
// calculates the x position of each item on mount and on layout change
const onItemLayout = React.useCallback(
(e: LayoutChangeEvent, index: number) => {
const x = e.nativeEvent.layout.x
setItemXs(prev => {
const Xs = [...prev]
Xs[index] = x
return Xs
})
},
[],
)
return (
<View testID={testID} style={[pal.view, styles.outer]}>
<DraggableScrollView
testID={`${testID}-selector`}
horizontal={true}
showsHorizontalScrollIndicator={false}
ref={scrollElRef}
contentContainerStyle={styles.contentContainer}>
{items.map((item, i) => {
const selected = i === selectedPage
return (
<PressableWithHover
testID={`${testID}-selector-${i}`}
key={`${item}-${i}`}
onLayout={e => onItemLayout(e, i)}
style={styles.item}
hoverStyle={pal.viewLight}
onPress={() => onPressItem(i)}>
<View style={[styles.itemInner, selected && indicatorStyle]}>
<Text
type={isDesktop || isTablet ? 'xl-bold' : 'lg-bold'}
testID={testID ? `${testID}-${item}` : undefined}
style={selected ? pal.text : pal.textLight}>
{item}
</Text>
</View>
</PressableWithHover>
)
})}
</DraggableScrollView>
</View>
)
}
const desktopStyles = StyleSheet.create({
outer: {
flexDirection: 'row',
width: 598,
},
contentContainer: {
paddingHorizontal: 0,
backgroundColor: 'transparent',
},
item: {
paddingTop: 14,
paddingHorizontal: 14,
justifyContent: 'center',
},
itemInner: {
paddingBottom: 12,
borderBottomWidth: 3,
borderBottomColor: 'transparent',
},
})
const mobileStyles = StyleSheet.create({
outer: {
flexDirection: 'row',
},
contentContainer: {
backgroundColor: 'transparent',
paddingHorizontal: 8,
},
item: {
paddingTop: 10,
paddingHorizontal: 10,
justifyContent: 'center',
},
itemInner: {
paddingBottom: 10,
borderBottomWidth: 3,
borderBottomColor: 'transparent',
},
})