Updating a Hook at the Mount
Understand how React updates function components by creating and managing hooks during the initial mount. Explore the mechanism of appending hooks to the fiber, accessing hooks in subsequent updates, and maintaining persistent state across renders to optimize functional component behavior.
We'll cover the following...
Updating a function component
React updates a function component through an updateFunctionComponent function. The input arguments accept a Component function and its props input:
function updateFunctionComponent(Component, props) {// Initializing the previous hook to null (assumes it's used for managing state in the component)prevHook = null;// Invoking the function component to get its childrenlet children = Component(props);}
The main job of the update function is to invoke Component (props) to know the new children element. Taking a Title component as an example, when it gets to be updated, the updateFunctionComponent function invokes Title(). With that, the engine compares the element returned and what's on the screen and commits the ...