Use

[rickyrauch]

Hello,

I was expecting to use this component like this:

<Gallery>
<img src="" / >
<img src="" / >
<img src="" / >
<img src="" / >
</Gallery>

And I'm getting this error

TypeError: Cannot read property 'map' of undefined
    at Constructor.render (/Users/ricardorauch/Sites/rickyrauch.me/.next/dist/components/gallery.js:21:48)
    at /Users/ricardorauch/Sites/rickyrauch.me/node_modules/react/lib/ReactCompositeComponent.js:793:21
    at measureLifeCyclePerf (/Users/ricardorauch/Sites/rickyrauch.me/node_modules/react/lib/ReactCompositeComponent.js:74:12)

[afram]

Hi @rickyrauch

What does gallery.js look like?

[rickyrauch]

Hello @afram

Exactly as your example.

var React = require('react');
var Masonry = require('react-masonry-component');

var masonryOptions = {
    transitionDuration: 0
};

var Gallery = React.createClass({
    render: function () {
        var childElements = this.props.elements.map(function(element){
           return (
                <li className="image-element-class">
                    <img src={element.src} />
                </li>
            );
        });

        return (
            <Masonry
                className={'my-gallery-class'} // default ''
                elementType={'ul'} // default 'div'
                options={masonryOptions} // default {}
                disableImagesLoaded={false} // default false
                updateOnEachImageLoad={false} // default false and works only if disableImagesLoaded is false
            >
                {childElements}
            </Masonry>
        );
    }
});

module.exports = Gallery;

[afram]

This example expects elements to be passed into Gallery as a prop. I suspect this is where it's failing for you.

You probably want something more along the lines of:

var Gallery = React.createClass({
    render: function () {
        return (
            <Masonry
                className={'my-gallery-class'} // default ''
                elementType={'ul'} // default 'div'
                options={masonryOptions} // default {}
                disableImagesLoaded={false} // default false
                updateOnEachImageLoad={false} // default false and works only if disableImagesLoaded is false
            >
                { this.props.children }
            </Masonry>
        );
    }
});

Note how I use this.props.children inside Masonry

[rickyrauch]

@afram Thanks for clarifying,

I still want to use this

  <li className="image-element-class">
    <img src={element.src} />
  </li>

[afram]

No problem, that's easy done, though in a slightly different way to how you initially had it.

let elements = [
    {
        src: '/image1.jpg`
    },
    {
        src: '/image2.jpg`
    }
];

<Gallery elements={ elements } />

[rickyrauch]

Yes, that's what I did.

I think the best approach would be:

<Gallery>
<ul>
  <li className="image-element-class">
    <img src={element.src} />
  </li>
  <li className="image-element-class">
    <img src={element.src} />
  </li>
  <li className="image-element-class">
    <img src={element.src} />
  </li>
</ul>
</Gallery>

Thanks.

[afram]

That's really up to you :-)

I would ask the question "Why are images displayed in an unordered list?" - this example was largely to show people the component's flexibility.

Good luck, glad I could help :-)

[rickyrauch]

I'm not saying <ul>, my example tries to show my own code. Instead of <ul> could be <div>. Parent (div or ul) and its childs (div or li)

[afram]

No problem.

I'm closing this now as I hope I managed to answer your question.

Please reopen if you need to!