How do you Hover in ReactJS? - onMouseLeave not registered during fast hover over

HelpMeStackOverflowMyOnlyHope picture HelpMeStackOverflowMyOnlyHope · May 1, 2015 · Viewed 260.2k times · Source

How can you achieve either a hover event or active event in ReactJS when you do inline styling?

I've found that the onMouseEnter, onMouseLeave approach is buggy, so hoping there is another way to do it.

Specifically, if you mouse over a component very quickly, only the onMouseEnter event is registered. The onMouseLeave never fires, and thus can't update state... leaving the component to appear as if it still is being hovered over. I've noticed the same thing if you try and mimic the ":active" css pseudo-class. If you click really fast, only the onMouseDown event will register. The onMouseUp event will be ignored... leaving the component appearing active.

Here is a JSFiddle showing the problem: https://jsfiddle.net/y9swecyu/5/

Video of JSFiddle with problem: https://vid.me/ZJEO

The code:

var Hover = React.createClass({
    getInitialState: function() {
        return {
            hover: false
        };
    },
    onMouseEnterHandler: function() {
        this.setState({
            hover: true
        });
        console.log('enter');
    },
    onMouseLeaveHandler: function() {
        this.setState({
            hover: false
        });
        console.log('leave');
    },
    render: function() {
        var inner = normal;
        if(this.state.hover) {
            inner = hover;
        }

        return (
            <div style={outer}>
                <div style={inner}
                    onMouseEnter={this.onMouseEnterHandler}
                    onMouseLeave={this.onMouseLeaveHandler} >
                    {this.props.children}
                </div>
            </div>
        );
    }
});

var outer = {
    height: '120px',
    width: '200px',
    margin: '100px',
    backgroundColor: 'green',
    cursor: 'pointer',
    position: 'relative'
}

var normal = {
    position: 'absolute',
    top: 0,
    bottom: 0,
    left: 0,
    right: 0,
    backgroundColor: 'red',
    opacity: 0
}

var hover = {
    position: 'absolute',
    top: 0,
    bottom: 0,
    left: 0,
    right: 0,
    backgroundColor: 'red',
    opacity: 1
}

React.render(
    <Hover></Hover>,         
    document.getElementById('container')
)

Answer

Elon Zito picture Elon Zito · Feb 25, 2016

Have you tried any of these?

onMouseDown onMouseEnter onMouseLeave onMouseMove onMouseOut onMouseOver onMouseUp

SyntheticEvent

it also mentions the following:

React normalizes events so that they have consistent properties across different browsers.

The event handlers below are triggered by an event in the bubbling phase. To register an event handler for the capture phase, append Capture to the event name; for example, instead of using onClick, you would use onClickCapture to handle the click event in the capture phase.