IF KR is present in the icon's validation string and the icon is not the last icon in the window, pressing <Return> in the icon will move the caret to the beginning of the next writable icon in the window. If the icon is the last writable icon in the window the <Return> (Code 13) will be passed to the application as in WIMP 2.00.
IF KA is present in the icon's validation string, pressing the up or down arrow keys will move the caret to the previous or next writable icon in the window, retaining the same position in the string. Pressing up in the first writable icon in a window will move the caret to the last writable icon, and pressing down in the last icon will move the caret to the first icon.
IF KT is present in the icon's validation string, pressing TAB in the icon will move the caret to the beginning of the next writable icon in the window. Pressing Shift+TAB will move the caret to the beginning of the previous writable icon in the window, the caret wraps around from last to first and first to last as per arrow keys with KA.
IF KD is present in the icon's validation string, pressing any of <Copy>,<Delete>,<Shift>+<Copy>,<Ctrl>+U,<Ctrl>+Copy will notify the application with the appropriate key code as well as doing its defined action as defined in the RISC OS 2.00 PRM.
IF KN is present in the icon's validation string, the application will be notified about all key presses in the icon, even if they are handled by the WIMP.
Options can be combined by including more than one option letter after the K command (e.g. KAR will give the arrow and return functionality).
To change the pointer shape while over the icon.
Where <Type> is:
0 => normal single pixel border
1 => slab out
2 => slab in
3 => ridge
4 => channel
5 => action button (highlights when icon selected)
6 => default action button (highlights when icon selected)
7 => editable field
>= 8 => normal single pixel border
The second number relates to the highlight colour applied on border types 5,6. By default this is 14 but the validation string can over-ride this, when the icon is selected the foreground colour is retained and the background changes to the highlight colour.
The borders are plotted on the inside of the icon border and only if the border bit is set as well.