所以当我点击一个心形按钮时,我想用心形按钮列出一个清单。
我只希望一个按钮更改颜色。并保存当前按钮的颜色状态。
我的问题是,当我点击一个心脏按钮时,所有按钮都会更改颜色。
这是我的代码
import React, { Component } from 'react';
import {
StyleSheet,
Text,
View,
Button,
} from 'react-native';
import { ListItem } from 'react-native-elements'
import { Icon } from 'react-native-elements'
import Data from './src/data/sampledata.json';
export default class App extends Component<Props> {
constructor(props) {
super(props);
this.state = {
buttonColor: '#979797', // default button color goes here, grey is default
};
}
onButtonPress = () => {
if(this.state.buttonColor=='#ff002b')
{
this.setState({ buttonColor: '#979797' }) // grey
}
else {
this.setState({ …Run Code Online (Sandbox Code Playgroud) 嗨,我试图制作一个程序,将字符串中的单词修改为大写单词.
大写单词在这样的标签中:
the <upcase>weather</upcase> is very <upcase>hot</upcase>
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结果 :
the WEATHER is very HOT
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我的代码是这样的:
string upKey = "<upcase>";
string lowKey = "</upcase>";
string quote = "the lazy <upcase>fox jump over</upcase> the dog <upcase> something here </upcase>";
int index = quote.IndexOf(upKey);
int indexEnd = quote.IndexOf(lowKey);
while(index!=-1)
{
for (int a = 0; a < index; a++)
{
Console.Write(quote[a]);
}
string upperQuote = "";
for (int b = index + 8; b < indexEnd; b++)
{
upperQuote += quote[b];
}
upperQuote …Run Code Online (Sandbox Code Playgroud)