خاصيات تنسيق النصوص (Text Style Props) في React Native.
import React, { useState } from "react";
import { FlatList, Platform, ScrollView, Slider, StatusBar, StyleSheet, Switch, Text, TouchableWithoutFeedback, View } from "react-native";
const fontStyles = ["normal", "italic"];
const fontVariants = [
undefined,
"small-caps",
"oldstyle-nums",
"lining-nums",
"tabular-nums",
"proportional-nums"
];
const fontWeights = [
"normal",
"bold",
"100",
"200",
"300",
"400",
"500",
"600",
"700",
"800",
"900"
];
const textAlignments = ["auto", "left", "right", "center", "justify"];
const textDecorationLines = [
"none",
"underline",
"line-through",
"underline line-through"
];
const textDecorationStyles = ["solid", "double", "dotted", "dashed"];
const textTransformations = ["none", "uppercase", "lowercase", "capitalize"];
const textAlignmentsVertical = ["auto", "top", "bottom", "center"];
const writingDirections = ["auto", "ltr", "rtl"];
const App = () => {
const [fontSize, setFontSize] = useState(10);
const [fontStyleIdx, setFontStyleIdx] = useState(0);
const [fontWeightIdx, setFontWeightIdx] = useState(0);
const [lineHeight, setLineHeight] = useState(10);
const [textAlignIdx, setTextAlignIdx] = useState(0);
const [textDecorationLineIdx, setTextDecorationLineIdx] = useState(0);
const [includeFontPadding, setIncludeFontPadding] = useState(false);
const [textVerticalAlignIdx, setTextVerticalAlignIdx] = useState(0);
const [fontVariantIdx, setFontVariantIdx] = useState(0);
const [letterSpacing, setLetterSpacing] = useState(0);
const [textDecorationStyleIdx, setTextDecorationStyleIdx] = useState(0);
const [textTransformIdx, setTextTransformIdx] = useState(0);
const [writingDirectionIdx, setWritingDirectionIdx] = useState(0);
const [textShadowRadius, setTextShadowRadius] = useState(0);
const [textShadowOffset, setTextShadowOffset] = useState({
height: 0,
width: 0
});
return (
<View style={styles.container}>
<Text
style={[
styles.paragraph,
{
fontSize,
fontStyle: fontStyles[fontStyleIdx],
fontWeight: fontWeights[fontWeightIdx],
lineHeight,
textAlign: textAlignments[textAlignIdx],
textDecorationLine: textDecorationLines[textDecorationLineIdx],
textTransform: textTransformations[textTransformIdx],
textAlignVertical: textAlignmentsVertical[textVerticalAlignIdx],
fontVariant: [fontVariants[fontVariantIdx]],
letterSpacing,
includeFontPadding,
textDecorationStyle: textDecorationStyles[textDecorationStyleIdx],
writingDirection: writingDirections[writingDirectionIdx],
textShadowOffset,
textShadowRadius
}
]}
>
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industry. 112 Likes
</Text>
<ScrollView>
<View>
<Text>Common platform properties</Text>
<CustomSlider
label="Text Shadow Offset - Height"
value={textShadowOffset.height}
minimumValue={-40}
maximumValue={40}
handleValueChange={val =>
setTextShadowOffset(prev => ({ ...prev, height: val }))
}
/>
<CustomSlider
label="Text Shadow Offset - Width"
value={textShadowOffset.width}
minimumValue={-40}
maximumValue={40}
handleValueChange={val =>
setTextShadowOffset(prev => ({ ...prev, width: val }))
}
/>
<CustomSlider
label="Font Size"
value={fontSize}
maximumValue={40}
handleValueChange={setFontSize}
/>
<CustomPicker
label="Font Style"
data={fontStyles}
currentIndex={fontStyleIdx}
onSelected={setFontStyleIdx}
/>
<CustomPicker
label="Font Weight"
data={fontWeights}
currentIndex={fontWeightIdx}
onSelected={setFontWeightIdx}
/>
<CustomSlider
label="Line Height"
value={lineHeight}
minimumValue={10}
maximumValue={50}
handleValueChange={setLineHeight}
/>
<CustomPicker
label="Text Align"
data={textAlignments}
currentIndex={textAlignIdx}
onSelected={setTextAlignIdx}
/>
<CustomPicker
label="Text Decoration Line"
data={textDecorationLines}
currentIndex={textDecorationLineIdx}
onSelected={setTextDecorationLineIdx}
/>
<CustomSlider
label="Text Shadow Radius"
value={textShadowRadius}
handleValueChange={setTextShadowRadius}
/>
<CustomPicker
label="Font Variant"
data={fontVariants}
currentIndex={fontVariantIdx}
onSelected={setFontVariantIdx}
/>
<CustomSlider
label="Letter Spacing"
step={0.1}
value={letterSpacing}
handleValueChange={setLetterSpacing}
/>
<CustomPicker
label="Text Transform"
data={textTransformations}
currentIndex={textTransformIdx}
onSelected={setTextTransformIdx}
/>
</View>
{Platform.OS === "android" && (
<View style={styles.platformContainer}>
<Text style={styles.platformContainerTitle}>
Android only properties
</Text>
<CustomPicker
label="Text Vertical Align"
data={textAlignmentsVertical}
currentIndex={textVerticalAlignIdx}
onSelected={setTextVerticalAlignIdx}
/>
<CustomSwitch
label="Include Font Padding"
handleValueChange={setIncludeFontPadding}
value={includeFontPadding}
/>
</View>
)}
{Platform.OS === "ios" && (
<View style={styles.platformContainer}>
<Text style={styles.platformContainerTitle}>
iOS only properties
</Text>
<CustomPicker
label="Text Decoration Style"
data={textDecorationStyles}
currentIndex={textDecorationStyleIdx}
onSelected={setTextDecorationStyleIdx}
/>
<CustomPicker
label="Writing Direction"
data={writingDirections}
currentIndex={writingDirectionIdx}
onSelected={setWritingDirectionIdx}
/>
</View>
)}
</ScrollView>
</View>
);
}
const CustomSwitch = ({ label, handleValueChange, value }) => {
return (
<>
<Text style={styles.title}>{label}</Text>
<View style={{ alignItems: "flex-start" }}>
<Switch
trackColor={{ false: "#767577", true: "#DAA520" }}
thumbColor={value ? "#DAA520" : "#f4f3f4"}
onValueChange={handleValueChange}
value={value}
/>
</View>
</>
);
}
const CustomSlider = ({
label,
handleValueChange,
step = 1,
minimumValue = 0,
maximumValue = 10,
value
}) => {
return (
<>
{label && (
<Text style={styles.title}>{`${label} (${value.toFixed(2)})`}</Text>
)}
<View style={styles.wrapperHorizontal}>
<Slider
thumbTintColor="#DAA520"
minimumTrackTintColor="#DAA520"
minimumValue={minimumValue}
maximumValue={maximumValue}
step={step}
onValueChange={handleValueChange}
value={value}
/>
</View>
</>
);
}
const CustomPicker = ({ label, data, currentIndex, onSelected }) => {
return (
<>
<Text style={styles.title}>{label}</Text>
<View style={styles.wrapperHorizontal}>
<FlatList
bounces
horizontal
data={data}
keyExtractor={(item, idx) => String(item)}
renderItem={({ item, index }) => {
const selected = index === currentIndex;
return (
<TouchableWithoutFeedback onPress={() => onSelected(index)}>
<View
style={[
styles.itemStyleHorizontal,
selected && styles.itemSelectedStyleHorizontal
]}
>
<Text
style={{
textAlign: "center",
color: selected ? "black" : "grey",
fontWeight: selected ? "bold" : "normal"
}}
>
{item + ""}
</Text>
</View>
</TouchableWithoutFeedback>
);
}}
/>
</View>
</>
);
}
const styles = StyleSheet.create({
container: {
flex: 1,
paddingTop: StatusBar.currentHeight,
backgroundColor: "#ecf0f1",
padding: 8
},
paragraph: {
color: "black",
textDecorationColor: "yellow",
textShadowColor: "red",
textShadowRadius: 1,
margin: 24
},
wrapperHorizontal: {
height: 54,
justifyContent: "center",
color: "black",
marginBottom: 12
},
itemStyleHorizontal: {
marginRight: 10,
height: 50,
padding: 8,
borderWidth: 1,
borderColor: "grey",
borderRadius: 25,
textAlign: "center",
justifyContent: "center"
},
itemSelectedStyleHorizontal: {
borderWidth: 2,
borderColor: "#DAA520"
},
platformContainer: {
marginTop: 8,
borderTopWidth: 1
},
platformContainerTitle: {
marginTop: 8
},
title: {
fontWeight: "bold",
marginVertical: 4
}
});
export default App;
تُستخدم هذه الخاصية لتحديد ثخن الخط، ومعظم الخطوط تدعم القيمتين طبيعي 'normal'، وثخين 'bold'، بينما لا تدعم جميع الخطوط كلّ احتمالات القيم العدديّةٍ، لذا نختار أقرب قيمةٍ في هذه الحالة.
تُستخدم هذه الخاصية لتحديد محاذاة الخط، وتدعم منصّة iOS القيمة 'justify' فقط، وتقابلها القيمة left
على منصّة Android.