DateInput

Overview

DateInput is a lookless Control that composes one NaviusFieldSegment per year/month/day unit (plus non-focusable literal separators) inside its PART_Segments panel, built from the culture’s ShortDatePattern via SegmentLayoutBuilder and driven by the shared, WPF-free SegmentMath/ DateTimeSegment engine (Controls/Internal/SegmentEngine.cs, shared verbatim with NaviusTimeInput). No native WPF control edits a date as independently focusable, steppable segments (WPF’s own DatePicker edits as one masked text run), so this is a from-scratch spinbutton row rather than a re-templated native control.

Usage

xmlns:dateInput="clr-namespace:Navius.Wpf.Primitives.Controls.DateInput;assembly=Navius.Wpf.Primitives"

<dateInput:NaviusDateInput Value="{Binding DueDate, Mode=TwoWay}"
                           Granularity="day"
                           MinValue="{Binding EarliestDate}"
                           Required="True" />

Properties

Property	Type	Default	From	Description
Value	DateOnly?	null	NaviusDateInput	Two-way bindable by default.
Granularity	string	"day"	NaviusDateInput	"day" (y/m/d), "month" (y/m), or "year". Changing it at runtime rebuilds the segment layout and reseeds from Value, discarding in-progress typing.
MinValue	DateOnly?	null	NaviusDateInput	Drives IsOutOfRange/IsInvalidState; never clamps the composed value.
MaxValue	DateOnly?	null	NaviusDateInput	Same as MinValue, upper bound.
PlaceholderValue	DateOnly?	null (→ today)	NaviusDateInput	Basis an empty segment jumps to on the first Arrow key.
ReadOnly	bool	false	NaviusDateInput	Blocks every segment key (short-circuits in OnSegmentPreviewKeyDown).
Required	bool	false	NaviusDateInput	Drives IsInvalidState (Required && Value is null). Fixed in the M6 audit: previously a dead property with no effect.
Invalid	bool	false	NaviusDateInput	Force-invalid regardless of range/required state; ORed into IsInvalidState.
ForceLeadingZeros	bool	false	NaviusDateInput	Pads month/day (and the year to 4 digits) with leading zeros.
Culture	CultureInfo?	null (→ CultureInfo.CurrentCulture)	NaviusDateInput	Drives segment order and separators via ShortDatePattern.
Name	string?	null	NaviusDateInput	Marker-only (no native-form mirror is ported); shadows FrameworkElement.Name via new.
IsFilled	bool	false	NaviusDateInput	Read-only. True when any segment has a value.
IsOutOfRange	bool	false	NaviusDateInput	Read-only. True when the composed value is outside [MinValue, MaxValue].
IsInvalidState	bool	false	NaviusDateInput	Read-only. Invalid || IsOutOfRange || (Required && Value is null).
IsEnabled	-	-	Control	Disabled is not a separate DP: it maps directly onto the inherited Control.IsEnabled.
FlowDirection	-	-	Control (FrameworkElement)	Dir is not a custom string parameter: native FlowDirection drives ArrowLeft/ArrowRight segment-focus mirroring directly.

Methods

Method	Description
FocusFirstSegment()	Focuses the first editable segment cell; this port’s stand-in for the web contract’s Field.FocusControl hookup, since no ambient NaviusField integration exists between the two families yet.

Events

Event	Signature	Fires when
ValueChanged	RoutedPropertyChangedEventHandler<DateOnly?>	On every committing keystroke (Arrow/Page/digit/Home/End/Backspace) that changes the composed value, not only once fully composed.

Keyboard interactions

Key	Behavior
ArrowUp	+1, wraps at [Min, Max]; an empty segment reveals the placeholder basis (today, or PlaceholderValue) instead of stepping from nothing.
ArrowDown	-1, same wrap/placeholder-reveal rule.
PageUp	Steps by the segment’s page step (year 5, month 3, day 7).
PageDown	Steps back by the same page step.
Home	Jumps to Min, clears the type buffer.
End	Jumps to Max, clears the type buffer.
Backspace / Delete	Clears the segment to unfilled.
ArrowLeft	Moves focus to the previous segment (flipped to next under FlowDirection.RightToLeft).
ArrowRight	Moves focus to the next segment (flipped to previous under RTL).
Digit 0-9	Appends to the type buffer; auto-advances to the next segment when the candidate value exceeds what one more digit could stay within bounds for, or the buffer reaches its max digit count (4 for year, 2 for month/day); ignores RTL (always advances forward).

The day segment’s Max is recomputed from the current year/month after every value-changing key, clamping an out-of-range day down immediately (e.g. typing day “31” then changing month to February).

UIA mechanism

NaviusDateInputAutomationPeer (a FrameworkElementAutomationPeer) reports AutomationControlType.Group plus a read-only IValueProvider surfacing the composed value as an ISO yyyy-MM-dd string, matching the NaviusSelectAutomationPeer/NaviusTimePicker precedent since a template-only control otherwise exposes nothing over UIA. Each NaviusFieldSegment cell has its own NaviusFieldSegmentAutomationPeer reporting AutomationControlType.Spinner plus IRangeValueProvider (Minimum/Maximum/Value/SetValue), including the day-period segment where applicable (shared with TimeInput). An unfilled segment reports Value = NaN over IRangeValueProvider, a distinct empty signal independent of the visible placeholder token. Segment-engine and control-level behavior (27 [Fact] plus 1 [Theory] engine tests, 20 [StaFact] control/peer tests) is exercised by DateInputTests.cs against real hosted windows for focus travel, typed-digit composition, and both automation peers.

Web deltas

• No NaviusBubbleInput hidden form-mirror: this repo’s Select-family precedent already drops native-form wiring for Tier B controls; Name stays a marker-only property.
• No ambient NaviusField integration (that family is a sibling port, not cascaded): FocusFirstSegment() stands in for Field.FocusControl; IsFilled/IsOutOfRange/ IsInvalidState are public read-only DPs a Field port can read directly instead of an ApplyControlStateAsync push.
• Dir is WPF’s native FlowDirection, not a custom string parameter; ArrowLeft/ArrowRight segment-focus mirroring honors it exactly as the web’s MoveFocus does for Dir="rtl".
• Disabled maps onto the inherited Control.IsEnabled, not a separate dependency property.
• DefaultValue (the web’s uncontrolled-initial-value parameter) has no separate property: Value is a plain two-way DP, and WPF’s DP system needs no controlled/uncontrolled split.
• Placeholder rendering: an unfilled segment shows a unit-shorthand token ("yyyy"/"mm"/"dd") instead of the web’s literal aria-valuetext string "Empty", WPF’s own masked-input placeholder idiom.
• Month/day-name aria-valuetext is not ported: UIA’s IRangeValueProvider only exposes a numeric Value, so a screen reader hears the month as a number, not a localized name; reproducing it would need a second pattern layered on top, left as a follow-up.
• Segment row RTL fix (ADR-0006): the PART_Segments panel is pinned to FlowDirection="LeftToRight" in Themes/DateInput.xaml so the visual segment order (year/month/ day plus separators) never mirrors under an ambient RTL FlowDirection, while the surrounding control still carries the ambient FlowDirection that OnSegmentPreviewKeyDown reads correctly for ArrowLeft/ArrowRight focus-travel direction. Verified with a pixel-rendered RenderTargetBitmap diff (byte-for-byte identical segment layout between LTR and RTL) and locked in by DateInputTests.PartSegments_FlowDirectionPinnedToLeftToRight_* and PartSegments_ChildOrder_UnaffectedByFlowDirection.
• Known residual (M6 audit, a coverage gap rather than a defect): culture-driven segment ordering/separators is only exercised against CultureInfo.InvariantCulture in the test suite; no test drives a dd/MM/yyyy-style culture (e.g. en-GB/de-DE) through SegmentLayoutBuilder, so that specific coverage breadth is unverified. The underlying code is written generically and was not found to be wrong.

Captures

The DateInput Gallery page rendered at the pinned commit, in each theme.