Force a React Component to Re-Render

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The beauty of React components is that they automagically render and update based on a change in state or props; simply update the state from any place and suddenly your UI element updates -- awesome!  There may be a case, however, where you simply want to brute force a fresh render of a React component.

Note:  In most cases you should never force a React component to re-render; re-rendering should always be done based on state or props changes.  Nonetheless, I don't judge and there may be a case where you legitimately need to force a React component to re-render so let's have it!

Force React Component Render

There are multiple ways to force a React component render but they are essentially the same.  The first is using this.forceUpdate(), which skips shouldComponentUpdate:

someMethod() {
    // Force a render without state change...
    this.forceUpdate();
}

Assuming your component has a state, you could also call the following:

someMethod() {
    // Force a render with a simulated state change
    this.setState({ state: this.state });
}

This blog doesn't aim to be prescriptive, so I wont scold developers for using this brute force method.  Again, there's likely a better, more "React-y" way to render a component properly, but if you are desperate to get a component render on command, there are many ways to do so with React.

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Discussion

  1. I can’t think on a real case where this is useful. Can someone give examples?

    • One place I’ve heard this come up a bunch is the case where you’re using non-React widgetry inside React components.

    • In React Native, special kinds of values ie

      Animated

      are manipulated via a function call

      someAnimatedValue.setValue(someNumber)

      , which refreshes the value without updating the component State and, thereby, not triggering a re-render.

      this.forceUpdate()

      helps to trigger the re-render in this case.

    • Aaron

      When I have a controlled component such as an Input element handle updating some data, the value will be using data from states. If I also need to delete a row on the UI, I want to force the app to refresh the data because otherwise there is no state changed.

    • I have a list of notifications including relative timestamps, ie. “About 20 seconds ago”. The actual state of the component technically doesn’t change as time progresses, so it stays stuck there. By forcing an update every few seconds you can see the timestamps go up to “About 30 seconds” etc.

    • I just used this with an SSR-enabled app in which I use components that can only be imported client-side. And so I needed something to trigger a rerender once the dynamic import had finished.

  2. Dimitris Proios

    When using some other library that has logic that u cannot put in the parent component to update via props and setState on componentDid/WillUpdate will create update loop, it can be useful.
    Personnally I have used it in react virtualized library to update data that were not in props or state but in a component variable.

  3. Paul

    Totally wrong way to do this.
    the better way is to add a query param at the end of the image src. That works better than trying to forceupdate the component. Please disregard my comment above.

  4. Danny

    My use case for this comes from using Redux stores where I am passing store props to an external component, but this happens before I update the store from an XHR request, i.e. the local component mounts before it gets the new data.

    Even though UI elements get updated with the XHR response, the new store props are not being passed down to the external component. In order for that to happen I needed to use this.forceUpdate() which then passed the new store props to the external component to render the data and display on the local component.

    This worked great, thanks for the article!

  5. You can force rerender of component by simply updating it’s key

  6. Instead of this.setState({ state: this.state }); you could just write this.setState({});, but that will only trigger re-render is your component doesn’t implement shouldComponentUpdate (as, e.g., PureComponent).

  7. Nikhil D Thakkar

    Another situation would be wherein you want to add the components dynamically based on some user action.

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