react-component

问题 Is there a way to stop react re-rendering if only part of state changes? The problem is that every time I hover on a marker a popup is opened or closed and it causes all the markers to re-render even though mystate is not changing only activePlace state is changing. console.log(myState); is running every time I hover in and out of the marker. I tried to use useMemo hook but couldn't figure out how to use it. Any help? Here is my code: import React, { useEffect, useState } from 'react'; import

问题 Is there a way to stop react re-rendering if only part of state changes? The problem is that every time I hover on a marker a popup is opened or closed and it causes all the markers to re-render even though mystate is not changing only activePlace state is changing. console.log(myState); is running every time I hover in and out of the marker. I tried to use useMemo hook but couldn't figure out how to use it. Any help? Here is my code: import React, { useEffect, useState } from 'react'; import

问题 How to add some custom CSS styles to the Nav component to manage the padding between the nav items and make it float right of the page? const navbar = props => ( <Navbar collapseOnSelect expand="lg" bg="dark" variant="dark"> <Navbar.Brand href="#home">React-Bootstrap</Navbar.Brand> <Navbar.Toggle aria-controls="responsive-navbar-nav" /> <Navbar.Collapse id="responsive-navbar-nav"> <Nav className="mr-auto"> <Nav.Link href="#features">Home</Nav.Link> <Nav.Link href="#pricing">About Us</Nav.Link

问题 Preface I asked a similar question to this several days back and while related in nature I believe the solution will ultimately be different, so I am asking again in a different thread. CodeSanbox Example (Has Been updated to reflect the accepted answer) The issue: I'd like any external styles passed in with the className prop to have higher specificity than my custom components internal style. That way someone using it can adjust margins and padding. However, my components default internal

问题 Preface I asked a similar question to this several days back and while related in nature I believe the solution will ultimately be different, so I am asking again in a different thread. CodeSanbox Example (Has Been updated to reflect the accepted answer) The issue: I'd like any external styles passed in with the className prop to have higher specificity than my custom components internal style. That way someone using it can adjust margins and padding. However, my components default internal

问题 RELATED QUESTION OVER AT: Styles being overwritten by Material-UI style I am create a component library on top of Material UI. Using JSS I'd like to be able to pass in styles to my custom components. However, I'm having issues with material-ui's root styles having higher specificity than what I'm passing in. I have tried overwriting the material-ui components default styles with the classes syntax but it simply creates another class with a similar name and higher specificity (makeStyles-root

问题 RELATED QUESTION OVER AT: Styles being overwritten by Material-UI style I am create a component library on top of Material UI. Using JSS I'd like to be able to pass in styles to my custom components. However, I'm having issues with material-ui's root styles having higher specificity than what I'm passing in. I have tried overwriting the material-ui components default styles with the classes syntax but it simply creates another class with a similar name and higher specificity (makeStyles-root

问题 I started a new "Hello World" project on react which looks like that: import React, { Component } from 'react'; export class Home extends Component { displayName = Home.name state = { result: 0, val1: 0, val2: 0, } handleChangeOne = (event) => { this.setState({ val1: event.target.value }); } handleChangeTwo = (event) => { this.setState({ val2: event.target.value }); } add = () => { this.setState({ result: parseInt(this.state.val1) + parseInt(this.state.val2) }); } render() { return ( <div>

问题 I started a new "Hello World" project on react which looks like that: import React, { Component } from 'react'; export class Home extends Component { displayName = Home.name state = { result: 0, val1: 0, val2: 0, } handleChangeOne = (event) => { this.setState({ val1: event.target.value }); } handleChangeTwo = (event) => { this.setState({ val2: event.target.value }); } add = () => { this.setState({ result: parseInt(this.state.val1) + parseInt(this.state.val2) }); } render() { return ( <div>

问题 I did a lot of research on this but i am not getting any solutions so please look through and help me, Basically its like when we select a location on the map by dragging the marker ,i don't want the map to refresh and reset the values and also the pin is coming back to the center after re render takes place, Is there any solution in "shouldcomponentupdate" ?? which doesn't allow you to re render the whole thing but by keep updating the values which were retrieved like address ,lat and long