Quiz for Virtualization

Q1: What is virtualization in the context of React performance?

A. A. Rendering only visible parts of a large list B. B. Running React in a virtual machine C. C. Using virtual DOM for rendering D. D. Caching components for reuse

Q2: Which library is commonly used for list virtualization in React?

A. A. react-window B. B. redux C. C. react-router D. D. axios

Q3: How does virtualization improve performance?

A. A. Reduces the number of DOM nodes rendered B. B. Increases memory usage C. C. Loads all list items at once D. D. Blocks rendering

Q4: Which React feature is NOT directly related to virtualization?

A. A. React.memo B. B. react-window C. C. react-virtualized D. D. Virtual DOM

Q5: What problem does virtualization primarily address?

A. A. Rendering performance with large lists B. B. API request handling C. C. Component styling D. D. State management

Q6: Which of these is a feature of react-virtualized?

A. A. Windowing large lists and tables B. B. Managing global state C. C. Routing between pages D. D. Form validation

Q7: Does virtualization render off-screen elements?

A. A. No, only visible and a small buffer B. B. Yes, all at once C. C. Only after user clicks D. D. Never

Q8: Which React Hook might you use with virtualization?

A. A. useRef B. B. useState C. C. useEffect D. D. All of the above

Q9: Is virtualization only useful for vertical scrolling lists?

A. A. No, can also be used for grids and horizontal lists B. B. Yes, only vertical C. C. No, only for forms D. D. Yes, only tables

Q10: What is a common challenge when implementing virtualization?

A. A. Handling dynamic item heights B. B. Managing Redux store C. C. API error handling D. D. CSS styling

Q11: How does react-window differ from react-virtualized?

A. A. react-window is lighter and simpler B. B. react-window supports more features C. C. react-window is deprecated D. D. They are the same

Q12: Can virtualization be combined with infinite scrolling?

A. A. Yes, they complement each other B. B. No, they conflict C. C. Only for pagination D. D. Only for small lists

Q13: What is the main performance bottleneck virtualization aims to reduce?

A. A. DOM node count B. B. JavaScript parsing time C. C. Network latency D. D. CSS loading time

Q14: Does virtualization work with server-side rendering?

A. A. It can but may require hydration handling B. B. No, it does not C. C. Yes, automatically D. D. Only with Redux

Q15: Which of these is a side effect of virtualization?

A. A. Reduced memory usage B. B. Increased bundle size C. C. Slower initial load D. D. More HTTP requests

Q16: How do you handle scroll position in virtualized lists?

A. A. Using scroll event handlers and refs B. B. With Redux only C. C. With CSS only D. D. It is automatic always

Q17: What is the buffer in virtualization?

A. A. Extra items rendered outside the viewport for smooth scrolling B. B. Memory cache C. C. API request queue D. D. CSS margin

Q18: Which component property controls item size in react-window?

A. A. itemSize B. B. size C. C. height D. D. width

Q19: Is virtualization useful for small lists?

A. A. No, overhead may outweigh benefits B. B. Yes, always C. C. Only for tables D. D. Only for images