User:Andrew/LayoutPatterns/CommandPatterns

Purpose

Command patterns are determined by the command structure chosen for the application (simple, complex or very complex). Commands are defined as any function performed by the application based on user input. Commands that perform similar functions may be grouped together. The collection of commands and command groups make up the command structure of the application.

Early in the design of an application, it may be unclear what the command structure should be. Start by assuming a simple command structure and selecting an associated command pattern. As the design evolves, if the selected command pattern becomes inadequate for completing the primary tasks of the application, consider a command pattern for a more complex command structure.

Command patterns can be combined with navigation patterns to design the complete layout for your application.

Guidelines

Patterns for a simple command structure

• Use Menu Button command pattern when there are few globally applicable commands.
• Use Context Menu or Context Panel command patterns for commands specific to selected content.
• The menu button pattern can be combined with either of the context menu or context panel patterns.
• Commands can also be exposed by direct manipulation of content (drag, drop, buttons, search fields, pan, zoom, etc).
• For plasmoids, all commands must be exposed by direct manipulation of content - no menu button, context menu, or context panel.

Examples

Contacts, Chat client, Video conference, Calculator, Terminal, Plasmoids (panel applets and desktop widgets), Maps, Games, Image browser, Document viewer, Music player, Video player, Software installer, System Settings

Patterns for a complex command structure

• Use Toolbar + Menu Button command pattern when the number frequently used commands are about 8 or less, and the remaining commands are not essential to performing the primary task of the application. The toolbar pattern exposes the frequently used commands. The menu button pattern exposes a fuller representation the command structure.
• Commands are also exposed by the direct manipulation of content, context menus or context panel.

Examples

Web browser, File manager, Text editor, Email, Calendar, Image editor, Music player, Archiver

Patterns for a very complex command structure

• Use Menubar when access to the full command structure is necessary to complete the primary tasks of the application.
• Commands are also exposed using toolbars, context menus, a context panel or by direct manipulation of content, .

Examples

IDE, Text Editor(high-feature), Image editor(high-feature), Audio/video editor, Document editor(high-feature), Spreadsheet editor