A command key sequence is an event generated when the user holds down one of the Amiga keys (the ones with the fancy A) and presses one of the normal alphanumeric keys at the same time. There are two different command or Amiga keys, commonly known as the left Amiga key and the right Amiga key. Menu command key sequences are combinations of the right Amiga key with any alphanumeric character, and may be used by any program. These sequences must be accessed through the menu system. Command key sequences using the left Amiga key cannot be associated with menu items. Menu command key sequences, like the menus themselves, are only available for a window while that window is active. Each window may control these keys by setting keyboard shortcuts in the menu item structures which make up the window's menu strip. If the user presses a command key sequence that is associated with one of the menu items, Intuition will send the program an event that is identical to the event generated by selecting that menu item with the mouse. Many users would rather keep their hands on the keyboard than use the mouse to make a menu selection when accessing often repeated selections. Menu command key sequences allow the program to provide shortcuts to the user who prefers keyboard control. A command key sequence is associated with a menu item by setting the COMMSEQ flag in the Flags variable of the MenuItem structure and by placing the ASCII character (upper or lower case) that is to be associated with the sequence into the Command variable of the MenuItem structure. Command keys are not case sensitive and they do not repeat. Command keys are processed through the keymap so that they will continue to work even if the key value is remapped to another position. International key values are supported as long as they are accessible without using the Alt key (right-Amiga-Alt maps to the right mouse button on the mouse). Figure 6-4: Menu Items with Command Key Shortcuts When items have alternate key sequences, the menu boxes show a special Amiga key glyph rendered roughly one character span plus a few pixels from the right edge of the menu select box. The command key used with the Amiga key is displayed immediately to the right of the Amiga key image, at the rightmost edge of the menu select box (see figure). Space must be provided at the right edge of the select box for the Amiga key imagery and for the actual command character. Leave COMMWIDTH pixels on high resolution screens, and LOWCOMMWIDTH pixels on low resolution screens. The character's width may be calculated with the graphics library TextLength() call. In general, each column of items should leave enough room for the widest command character plus the width of the Amiga key imagery.