Gauge

Remarks

⚠ The other half of doc 49 § 7.1's rank 6, and the same control drawn round a circle. A level indicator is a bar because it sits in a row; a gauge is a dial because it sits on its own — a CPU load in a status panel, a frame budget in an overlay, a tank on a HUD. What the reading means is identical, so Warning, Critical, Direction and Level are the level indicator's, computed by the same code, and a bar and a dial over one number cannot disagree about whether it is a problem.

⚠ The dial opens at the bottom and fills clockwise from its lower left. That is what a speedometer, a pressure gauge and every audio meter with a needle does, and the gap is where a caption goes. Sweep is how much of the turn it spans.

No needle and no text. The filled arc is the needle — a needle is one more thing to antialias at every angle and says nothing the arc's end does not — and the number in the middle is the application's, for LevelIndicator's reason: "87 %" is not a sentence this assembly can write without knowing what is being measured. Put a label over it.

⚠ Orientation means nothing to a dial and is ignored. It is inherited because the bounds, the step and the colours are, and those are the part of RangeBase a gauge needs.

Fields and properties (15)

• protected override string TagName

  The element name this type answers to when a caller does not choose one.

• protected override bool AcceptsFocus
• protected override AccessibleRole NativeRole
• protected override string? NativeAccessibleValue
• public float Value
• public float Warning
• public float Critical
• public LevelDirection Direction
• public float Sweep
• public LevelReading Level

  What the reading currently amounts to.

• public static readonly UiPropertyKey ValueProperty

  Identity for Value.

• public static readonly UiPropertyKey WarningProperty

  Identity for Warning.

• public static readonly UiPropertyKey CriticalProperty

  Identity for Critical.

• public static readonly UiPropertyKey DirectionProperty

  Identity for Direction.

• public static readonly UiPropertyKey SweepProperty

  Identity for Sweep.

Methods (7)

• protected override void OnCreated()

  Builds whatever this element is made of, once, as it joins a document.

• protected override void OnDraw(DrawContext context)
• public void ClearValue()

  Unsets Value, so it takes its default or its ancestor's value again.

• public void ClearWarning()

  Unsets Warning, so it takes its default or its ancestor's value again.

• public void ClearCritical()

  Unsets Critical, so it takes its default or its ancestor's value again.

• public void ClearDirection()

  Unsets Direction, so it takes its default or its ancestor's value again.

• public void ClearSweep()

  Unsets Sweep, so it takes its default or its ancestor's value again.

Used by (3)

• GalleryHelloUi
• GaugeTestsVixen.Ui.Controls.Tests
• LevelIndicatorImageTestsVixen.Graphics.Golden.Tests