Modal views, also known as modal dialogs or modal windows, are a common UI element in software applications. A modal view is a type of graphical user interface component that appears on top of the main application window and requires the user to interact with it before returning to the main application.

Here are some key characteristics and use cases of modal views:

1. User focus: Modal views are designed to grab the user's attention and restrict interaction with the underlying application until a specific action is taken. They typically contain critical information that requires immediate user input or confirmation.
2. Block interaction: Modal views create a modal state where interaction with the rest of the application is temporarily blocked. Users must complete or dismiss the modal view before continuing with other tasks.
3. Limited scope: Modal views often have a specific purpose or functionality, such as displaying error messages, requesting user input, or confirming an action. They are typically used for short and focused tasks.
4. Clear hierarchy: Modal views have a distinct visual hierarchy compared to the main application window. They usually appear as separate windows or overlays, with the main application window, dimmed or partially obscured to signify the temporary focus on the modal view.
5. Return values: Modal views commonly return a result or user input to the main application once the interaction is complete. This allows the application to respond appropriately based on the user's choices.

Some common examples of modal views include:

• Alert dialogs: Used to display important messages, warnings, or errors that require immediate user attention.
• Confirmation dialogs: Used to prompt the user for confirmation before executing a potentially destructive action, such as deleting a file or closing unsaved changes.
• Form dialogs: Used to gather user input for specific tasks, such as creating a new account or editing profile information. The main application waits for the user to complete the form before proceeding.
• File pickers: Used to select files or directories from the file system, restricting the user's interaction with the rest of the application until the selection is made.
• Login dialogs: Used to authenticate the user before granting access to certain features or secure areas of the application.

Modal views enhance the user experience by providing focused interactions, guiding users through important tasks, and preventing accidental actions. However, it's essential to use them wisely to avoid overwhelming or frustrating users with too many interruptions or complex modal interactions.