HidP_MaxUsageListLength function (hidpi.h)

The HidP_MaxUsageListLength routine returns the maximum number of HID usages that HidP_GetUsages can return for a specified type of HID report and a specified top-level collection.

Syntax

ULONG HidP_MaxUsageListLength(
  [in] HIDP_REPORT_TYPE     ReportType,
  [in] USAGE                UsagePage,
  [in] PHIDP_PREPARSED_DATA PreparsedData
);

Parameters

[in] ReportType

Specifies a HIDP_REPORT_TYPE enumerator value that indicates the report type.

[in] UsagePage

Specifies a usage page as a search criteria. If UsagePage is zero, the routine returns the number of all the buttons in the collection.

[in] PreparsedData

Pointer to a top-level collection's preparsed data.

Return value

If successful, HidP_MaxUsageListLength returns the maximum number of HID usages that HidP_GetUsages can return for a specified type of HID report and a specified top-level collection. If the specified preparsed data or report type is not valid, the routine returns zero.

Remarks

For more information, see HID Collections.

Requirements

See also

HidP_GetButtons

HidP_GetUsages

_HIDP_PREPARSED_DATA