Oscar Franco

React Native, hot module hooks

August 2023

In some cases you might want to clear listeners or state when a fast-refresh/hot-reload cycle happens. You can do so by hooking up to the hot module:

module.hot?.accept(() => {

This will only be called once the new module is mounted, this means any reference the previous in-memory module had, will not be there. Sometimes you really need a reference to an old object to clean it, you can use the counter part dispose:

module.hot?.dispose(() => {

Take note of the optional chaining operator, when compiling the app on production the hot module will not be there, causing a crash if trying to be called.