Vuejs lifecycle hooks

1. Can you explain the different lifecycle hooks in Vue.js and their use cases?

beforeCreate:

Use Case: This hook is called right after the instance has been initialized but before data observation and event/watcher setup. It's rarely used but can be useful for early initialization logic.

Example: Setting up default values or initial states that do not rely on reactive data.

created:

Use Case: This hook is called after the instance has been created, data observation is set up, and computed properties and methods are available, but the DOM has not yet been mounted. It's often used for fetching initial data.

Example: Making API calls to fetch data to populate the component.

beforeMount:

Use Case: Called right before the mounting begins, i.e., before the render function is called for the first time. It's rarely used directly.

Example: Manipulating the DOM or performing operations before the initial render.

mounted:

Use Case: Called after the component has been mounted to the DOM. It's commonly used to perform actions that require access to the actual DOM nodes.

Example: Initializing third-party libraries that need DOM elements or accessing/manipulating the DOM.

beforeUpdate:

Use Case: Called when data changes, right before the virtual DOM is patched. This hook allows for preparations before the DOM is updated.

Example: Logging data changes or performing computations based on new data before the view updates.

updated:

Use Case: Called after the component’s DOM has been updated. This can be used to perform post-update DOM manipulations.

Example: Running code that needs the DOM to be in its updated state, like updating charts or other visualizations

beforeDestroy:

Use Case: Called right before a component instance is destroyed. This is the time to clean up anything that was set up during the lifecycle of the component.

Example: Removing event listeners, stopping timers, or canceling network requests.

destroyed:

Use Case: Called after a component instance has been destroyed. The component’s directives, child components, and event listeners have been removed. This hook can be used for final cleanup.

Example: Performing final cleanup actions such as logging the destruction of the component for analytics.

activated (used with keep-alive):

Use Case: Called when a kept-alive component is activated. This is specific to components wrapped in <keep-alive>.

Example: Re-fetching data or re-initializing settings when the component is activated.

deactivated (used with keep-alive):

Use Case: Called when a kept-alive component is deactivated. This hook can be used to perform tasks like pausing updates or saving state.

Example: Pausing timers or saving scroll positions when the component is deactivated.

errorCaptured:

Use Case: Called when an error from a child component is captured. This hook can be used for error reporting or displaying fallback UI.

Example: Logging errors to an external service or displaying a user-friendly error message.

Summary of Usage in the Component Lifecycle

Initialization: beforeCreate, created

Mounting: beforeMount, mounted

Updating: beforeUpdate, updated

Destruction: beforeDestroy, destroyed

Keep-Alive Components: activated, deactivated

Error Handling: errorCaptured

Each of these hooks serves a specific purpose and allows you to hook into different moments of a component's lifecycle, providing fine-grained control over your component behavior.