Lesson_67

date element

date input element is used to store date (https://edk2-docs.gitbook.io/edk-ii-vfr-specification/2_vfr_description_in_bnf/211_vfr_form_definition#2.11.6.9-vfr-date-statement-definition)

Add this code to UefiLessonsPkg/HIIFormDataElements/Form.vfr:

date
  varid = FormData.DateValue,
  prompt = STRING_TOKEN(DATE_PROMPT),
  help = STRING_TOKEN(DATE_HELP),
enddate;

Add strings to UefiLessonsPkg/HIIFormDataElements/Strings.uni

#string DATE_PROMPT            #language en-US  "Date prompt"
#string DATE_HELP              #language en-US  "Date help"

Date is encoded in special EFI_HII_DATE type (https://github.com/tianocore/edk2/blob/master/MdePkg/Include/Uefi/UefiInternalFormRepresentation.h):

typedef struct {
  UINT16    Year;
  UINT8     Month;
  UINT8     Day;
} EFI_HII_DATE;

Therefore add it to our structure in UefiLessonsPkg/HIIFormDataElements/Data.h:

typedef struct {
  ...
  EFI_HII_DATE DateValue;
} UEFI_VARIABLE_STRUCTURE;

This will result to this element:

The value is displayed in MM/DD/YYYY format. So it is possible to store 02/20/2022, but not 20/02/2022.

As for checks, even the leap year is checked. You can enter 02/29/2020, but not 02/29/2021.

time element

time VFR input element is used to store time (https://edk2-docs.gitbook.io/edk-ii-vfr-specification/2_vfr_description_in_bnf/211_vfr_form_definition#2.11.6.10-vfr-time-statement-definition)

Add this code to UefiLessonsPkg/HIIFormDataElements/Form.vfr:

time
  varid = FormData.TimeValue,
  prompt = STRING_TOKEN(TIME_PROMPT),
  help = STRING_TOKEN(TIME_HELP),
endtime;

Add strings to UefiLessonsPkg/HIIFormDataElements/Strings.uni

#string TIME_PROMPT            #language en-US  "Time prompt"
#string TIME_HELP              #language en-US  "Time help"

Time is encoded in special EFI_HII_TIME type (https://github.com/tianocore/edk2/blob/master/MdePkg/Include/Uefi/UefiInternalFormRepresentation.h):

typedef struct {
  UINT8    Hour;
  UINT8    Minute;
  UINT8    Second;
} EFI_HII_TIME;

Therefore add it to our structure in UefiLessonsPkg/HIIFormDataElements/Data.h:

typedef struct {
  ...
  EFI_HII_TIME TimeValue;
} UEFI_VARIABLE_STRUCTURE;

This will result to this element:

As with date element HII Form Browser doesn't allow to set invalid time values.