Not returning a React Element

I was following a tutorial on a simple react motion transition however I am getting the following error

bundle.js:4882 Warning: Transition(…): A valid React element (or null) must be returned. You may have returned undefined, an array or some other invalid object.

Here is the code for the Transition component `export default function Transition (props) { let defaultStyles = [], styles = []; const {children} = props; React.Children.map(children, (child)=>{

    if(child){
        defaultStyles.push({
            key: child.key,
            data: child,
            style: {opacity: 0}
        });

        styles.push({
            key: child.key,
            data: child,
            style: {opacity: spring(1)}
        })
    }
});

function willEnter() {
    return {opacity: 0}
}

function willLeave() {
    return {opacity: spring(0, {stiffness: 90, damping: 11})}
}

console.log(styles, defaultStyles);

<TransitionMotion styles={styles} defaultStyles={defaultStyles} willEnter={willEnter} willLeave={willLeave} children={props.children}>
    {
        (styles)=>{
            return(
                <div>
                    {
                        styles.map((child)=>{
                            if(child){
                                const {key, data, style} = child;
                                return React.cloneElement(
                                    data,
                                    {key, style}
                                )
                            }else{
                                return null
                            }

                        })
                    }
                </div>
            )
        }
    }
</TransitionMotion>

}`

and here is how I am trying to implement it

`class GroupItem extends Component{

render(){
    return(
        <Transition>
            {<div key="1">Hello there</div>}
        </Transition>
    )
}

}

Any help would be great `

[bloodyowl]

https://jsfiddle.net/69z2wepo/89552/ there were some errors here, but the main one was that you didn’t return the TransitionMotion component

[takahiro-saeki]

@Craques if you could resolve this problem, you might have better close this issue.