DropDown

DropDown Component Summary

Overview

The DropDown component is a reusable dropdown menu that displays a button and a list of selectable items. It leverages Material-UI components for consistent styling and behavior.

Usage

To use the DropDown component, import it and provide an array of menu items, each containing an item name and a callback function.

Input and Return Types

Props:

• [menuItems]: An array of objects, each with:
  • [item]: A string representing the menu item name.
  • [callback]: A function to be called when the item is selected.
• [isMobile] (optional): A boolean indicating if the dropdown is displayed on a mobile device. This is used to inform the component if it should be rendered in a mobile or desktop state.
• [defaultValue] (optional): A string representing the default selected item. It must be a value in menuItems. If it is not provided, the first menuItem is the default.
• [className] (optional): A string for custom CSS class. This is normally used to add your own custom styling to the component.
• [icon] (optional): If true, a dropdown arrow will be displayed. If false, no icon is shown.

Example Usage

const menuItems = [
  { item: 'Price', callback: () => setSortBy('avgPrice') },
  { item: 'Rating', callback: () => setSortBy('avgRating') },
  { item: 'Date Added', callback: () => setSortBy('id') },
];

function App() {
  return <DropDown menuItems={menuItems} defaultValue={'Rating'} icon={true}/>;
}

Expected Behavior

• The component renders a button with the default or first menu item displayed.
• Clicking the button opens a dropdown menu with the provided items.
• Selecting an item triggers its callback function and updates the button text to the selected item.

Edge Cases

• Empty menuItems array: The component handles this by displaying an empty menu.
• Duplicate item names: Callbacks are correctly associated with their respective items even if there are multiple items with the same name.
• Long item names: This is not handled by the component and relies on the client's personal styling through the className prop

Implementation Strategy

• State Management: Use useState to manage the selected item and the dropdown's open state.
• Event Handling: Implement handlers for button clicks and menu item selection.
• Styling: Use Material-UI's Button, Menu, and MenuItem components for consistent styling.
• Accessibility: Ensure the component is accessible by setting appropriate ARIA attributes.

Runtime Analysis

• Initialization: O(1) for setting initial state.
• Rendering: O(n) where n is the number of menu items, as each item is rendered in the dropdown.
• Event Handling: O(1) for handling clicks and state updates.