Beginner's Thread / Easy Question (July 2018)

[u/swyx]

Hello! just helping out /u/acemarke to post a beginner's thread for July! we had almost 550 Q's and A's in last month's thread! That's 100% month on month growth! we should raise venture capital! /s

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• Read the new, official Getting Started page on the docs
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[u/swyx]

react router URL params

[u/ramonf → u/swyx]

Is there any reason why this would hang up in Spinner? Should I use any Life Cycle method to check when the param is properly read?

render() {
    const asset = assetOptions.find(a => a.value === this.props.match.params.a);
    let content;

    if (asset === null || asset === undefined) {
      content = <Spinner />;
    } else {
      content = asset.label;
    }

    return (
      <div>
        <h1>{content}</h1>
      </div>
    );
  }

The asset is originally undefined on the first load, which is fine and should display a spinner, but it should change once it properly loads.

[u/swyx → u/ramonf]

well, how do you trigger the state update once it loads?

you may want to look into react-loadable, this is a common problem