UITableView & UICollectionView
UITableView, UICollectionView, data sources, delegates, cell reuse, custom cells
1What is the main purpose of the dequeueReusableCell method in UITableView?
What is the main purpose of the dequeueReusableCell method in UITableView?
回答
The dequeueReusableCell method retrieves a reusable cell from the recycling pool. This optimizes memory by reusing off-screen cells rather than creating new instances constantly. This is critical for maintaining smooth performance during scrolling.
2Which UITableViewDataSource method returns the number of rows in a given section?
Which UITableViewDataSource method returns the number of rows in a given section?
回答
The tableView(_:numberOfRowsInSection:) method from UITableViewDataSource returns the row count for each section. It's called by UITableView to calculate total height and manage cell recycling. This method is mandatory to implement.
3What is the main advantage of using UICollectionViewFlowLayout over a custom layout?
What is the main advantage of using UICollectionViewFlowLayout over a custom layout?
回答
UICollectionViewFlowLayout provides a prebuilt optimized grid layout that automatically handles spacing, alignment, and cell wrapping. It avoids implementing complex layout logic and is highly configurable through properties like minimumLineSpacing, itemSize, and sectionInset.
How to combine numberOfSections and numberOfRowsInSection methods for a multi-section structure?
Which protocol provides methods for handling selection events in a UICollectionView?
+22 面接問題