HidP_GetButtonsEx
This macro is a mnemonic alias for the HidP_GetUsagesEx function.
#define HidP_GetButtonsEx(Rty, LCo, BLi, ULe, Ppd, Rep, RLe) \
HidP_GetUsagesEx(Rty, LCo, BLi, ULe, Ppd, Rep, RLe)
Parameters
- Rty
[in] HIDP_REPORT_TYPE enumerator value that identifies the report type. - LCo
[in] 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 the buttons in the top-level collection associated with PreparsedData. - BLi
[out] Pointer to a caller-allocated buffer that function uses to return the usage and usage page identifiers for each button that is set to ON (one). - ULe
[in, out] On input, the length, in array elements, of the ButtonList buffer. On output, the number usages that are currently set to ON in the specified report. - Ppd
[in] Pointer to a top-level collection's preparsed data. - Rep
[in] Pointer to a report that contains button data. - RLe
[in] Length, in bytes, of the report located at Report.
Return Values
The following table shows the possible return values for this function.
Value | Description |
---|---|
HIDP_STATUS_SUCCESS | The function successfully returned all button usages that were set to ON. |
HIDP_INVALID_REPORT_LENGTH | Report length was not valid. |
HIDP_INVALID_REPORT_TYPE | Specified report type was not valid. |
HIDP_STATUS_BUFFER_TOO_SMALL | UsageList buffer was too small to hold all the usages currently set to ON in the specified report. |
HIDP_STATUS_INCOMPATIBLE_REPORT_ID | Report contained a collection with buttons in the specified usage page, but there were no such usages in the report. |
HIDP_STATUS_INVALID_PREPARSED_DATA | Report contained a requested usage that were not in any report supported by the top-level collection. |
Remarks
The terms button and usage are used synonymously.
HID clients call HidP_MaxUsageListLength to determine the maximum number of buttons that this function can return for aspecified report type. Alternatively, applications or drivers can call HidP_GetUsagesEx 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
OS Versions: Windows CE .NET 4.2 and later.
Header: Hidpi.h.
See Also
HID Drivers | HIDP_CAPS | HidP_GetCaps | HidP_GetUsagesEx | HidP_MaxUsageListLength | HIDP_REPORT_TYPE | USAGE_AND_PAGE
Last updated on Tuesday, May 18, 2004
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