A fast and easily customised operating system
for ARM devices
AutoScroll Block
WindowManager
» SWI Calls
» Wimp_AutoScroll
» AutoScroll Block
AutoScroll Block
| Offset | Contents |
|---|---|
| +0 | Window handle of window to scroll |
| +4 | Left pause zone width |
| +8 | Bottom pause zone height |
| +12 | Right pause zone width |
| +16 | Top pause zone height |
| +20 | Pause duration in centiseconds |
| -1 configured pause length, or | |
| 0 no pause, or | |
| Other durations in centiseconds | |
| +24 | State change handler |
| 0 none, or | |
| 1 use Wimp’s pointer shape routine, or | |
| >1 pointer to a routine | |
| +28 | Handle. Value to pass in R12 to state change handler routine (if applicable) |
Notes
This block is used in conjunction with Wimp_AutoScroll to specify how automatic scrolling is handled by an application (if bit 0 or bit 1 is set).
Zone sizes are in OS units, and are ignored unless the relevant flag bit is set. A sensible default for these is 80.
The state change handler is entered every time the status flags change with r0 = old status flags, r1= new status flags and r12=AutoScroll block handle.
The wimp’s default routine changes the pointer shape of the pointer depending on the status flags.
See also
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