A file dialog, also known as a file chooser or requester, is a graphical control element that enables users to select a file from the file system. Unlike file managers, file dialogs focus on opening and saving files rather than full file management, though some support simple tasks like creating and renaming folders. Prior to their use, users either supplied files via command line arguments or selected files through file managers. File dialogs provide a standardized, secure method for applications to access individual files with user consent. However, many mobile operating systems do not include file dialogs, instead granting apps broader access to the file system.
Types
There are several types of file dialogs, the two most common being a two-column "view file" dialog and a mini file browser dialog. Others include thumbnail view (for photos) and metadata (for music). There are several reasons for the many varieties of dialogs. First of all there is no single standard design, so a program may implement their own for any purpose. Many GUI toolkits do not provide a file dialog, so an application is forced to use its own.
Two-column view
The two-column view is one of the primary file dialog types. It uses two columns. One for folders, and another for files. Other common features include the current folder name, a search box and buttons for basic file manipulation.
Mini file manager
A mini file manager is often used. It represents the normal file manager, but it is restricted in its operations.
Thumbnails
Usually used by image related applications, a gallery of files are shown which allow a file to be chosen graphically.
Usability
File dialogs have been a subject of much usability debate. As a graphical control element receiving constant use, ease of use is a major factor in their design. The most common reasons for file dialog usability problems include:
- File system limitations,
- Wrong type of dialog for the application (e.g. no thumbnail view in a Wallpaper Selector, As in GNOME 2.6),
- Horizontal scrolling (As in Windows file dialogs),
- Uses non standard terminology (Commonly in ports from other operating systems)
Many widget libraries toolkits such as GTK have been criticized for their lack of it. Early versions of Microsoft Windows also suffered from problems, mainly from the DOS legacy behind it. However, most of these are being addressed as more legacy programs are being converted to use newer, more usable file dialogs.
Powerbox
A file powerbox is a file dialog which dynamically grants the application that opened it the right to access the file that the user chooses.
This means that an application does not have to run with the user's full authority. In other words, the application does not have to have the right to access all the user's files. An important aspect of the powerbox interface is that it can look to the user just like any other insecure file dialog, but can act to protect the bulk of the user's files from potentially untrustworthy software such as Trojan horses or other forms of malware.
With a powerbox system, the file dialog is implemented as a trusted part of the system. It runs in a protection domain separate from the application. The powerbox component has access to all the user's files, whereas the application does not.
Apple Mac OS X Lion and later versions of macOS use a powerbox to allow sandboxed applications to open and save files.1
Images
See also
External links
References
John Siracusa (July 20, 2011). "Mac OS X 10.7 Lion: the Ars Technica review". ArsTechnica. https://arstechnica.com/apple/reviews/2011/07/mac-os-x-10-7.ars/9#powerbox ↩