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HidP_GetUsages (Windows Embedded CE 6.0)

  • Статья

1/6/2010

This function returns a list of the HID control button usages that are in a specified usage page and are set to On in a HID report.

Syntax

NTSTATUS HidP_GetUsages(
  HIDP_REPORT_TYPE ReportType,
  USAGE UsagePage,
  USHORT LinkCollection,
  USAGE* UsageList,
  ULONG* UsageLength,
  PHIDP_PREPARSED_DATA PreparsedData,
  PCHAR Report,
  ULONG ReportLength
);

Parameters

  • ReportType
    [in] HIDP_REPORT_TYPE enumerator value that identifies the report type.
  • UsagePage
    [in] Usage page of the button usages. The function only returns information about buttons in this usage page
  • LinkCollection
    [in] Optional. Link collection of the button usages. If LinkCollection is nonzero, the function only returns information about the buttons that this link collection contains; otherwise, if LinkCollection is zero, the function returns information about all the buttons in the top-level collection associated with PreparsedData.
  • UsageList
    [out] Pointer to a caller-allocated buffer that the function uses to return the usages of all buttons that are set to On and belong to the usage page specified by UsagePage.
  • UsageLength
    [in, out] On input, the length in array elements of the UsageList buffer. On output, the number of buttons set to On in the specified usage page.
  • PreparsedData
    [in] Pointer to a top-level collection's preparsed data.
  • Report
    [in] Pointer to a report.
  • ReportLength
    [in] Length, in bytes, of the report located at Report.

Return Value

The following table shows the possible return values.

Value Description

HIDP_STATUS_SUCCESS

The function successfully returned all button usages set to On.

HIDP_INVALID_REPORT_LENGTH

Report length is not valid.

HIDP_INVALID_REPORT_TYPE

Specified report type is not valid.

HIDP_STATUS_BUFFER_TOO_SMALL

In the specified usage page, UsageList buffer is too small to hold all the usages that are currently set to On.

HIDP_STATUS_INCOMPATIBLE_REPORT_ID

Report contains a collection with buttons in the specified usage page, but there are no such usages in the report.

HIDP_STATUS_INVALID_PREPARSED_DATA

Preparsed data is not valid.

HIDP_STATUS_USAGE_NOT_FOUND

Report contains a requested usage that is not in any report supported by the top-level collection.

Remarks

The terms button and usage are used synonymously.

User-mode applications and kernel-mode drivers call HidP_MaxUsageListLength to determine the maximum number of buttons that this function can return for a specified report type. Alternatively, applications or drivers can call HidP_GetButtons and set UsageList to zero to return the required length in UsageLength.

Applications or drivers determine the required report length from the XXXReportByteLength members in a top-level collection's HIDP_CAPS structure.

Requirements

Header hidpi.h
Library Hidparse_lib.lib
Windows Embedded CE Windows CE .NET 4.2 and later

See Also

Reference

HID Parser Functions
HIDP_CAPS
HidP_GetButtons
HidP_GetButtonsEx
HidP_GetCaps
HidP_GetScaledUsageValue
HidP_GetUsagesEx
HidP_GetUsageValue
HidP_GetUsageValueArray
HidP_MaxUsageListLength
HIDP_REPORT_TYPE