* RTL support for **all** Krypton.Toolkit controls

[PWagner1]

Feature: Toolkit RTL layout (#2379)

Summary

Krypton.Toolkit now uses the same two-flag RTL contract as KryptonForm and KryptonRibbon: RightToLeft.Yes plus RightToLeftLayout mirrors layout (docks, splitters, captions, spin chrome). RightToLeft alone still controls reading order and Near/Far content.

Related issues

• Closes [Feature Request]: RTL support for **all** Krypton.Toolkit controls #2379

Type of change

• Feature / enhancement (Implemented)

Changes

• Lifted RightToLeftLayout onto VisualControlBase, VisualPanel, and VisualContainerControlBase.
• Added ToolkitRtlLayout helpers and ViewDrawDocker.IgnoreRightToLeftLayout.
• CheckBox/RadioButton dockers ignore auto-flip so glyph docks are not inverted twice.
• NumericUpDown/DomainUpDown move spin buttons to the start edge when both flags are set.
• ListBox/CheckedListBox/RichTextBox forward RightToLeft to the inner native control.
• SplitContainer, GroupBox, and HeaderGroup pick up docker/panel mirroring via the new layout flag.
• DateTimePicker, TreeView, ListView, and Ribbon keep specialised layout flags in sync with the base property.
• Context menus copy both flags onto the popup; submenus open toward the start edge; CommandLink arrows and TaskDialog columns mirror; PropertyGrid forwards RightToLeft to the inner grid.

Affected packages & target frameworks

• Packages: Krypton.Toolkit, Krypton.Toolkit.Utilities (CommandLink arrow), Krypton.Ribbon (KryptonRibbon.RightToLeftLayout is now an override).
• TFMs verified: net472

Validation

• TestForm demo: RTLControlsTest (StartScreen: RTL Compliance Tests).
• Standard-Toolkit-Demos: Krypton RTL Examples on branch alpha-2379-toolkit-rtl.
• Manual steps:
  1. Open RTL Compliance Tests.
  2. Click Toggle RTL (sets both flags).
  3. Confirm calendars, NUD spin buttons, lists, split, group/header, checkbox/radio, CommandLink arrow, context menu packing, PropertyGrid, and TaskDialog columns mirror; caption text stays readable.
• Build: dotnet build ".\Source\Krypton Components\Krypton.Toolkit\Krypton.Toolkit 2022.csproj" -c Debug -f net472
• Screenshots: powershell -NoProfile -ExecutionPolicy Bypass -STA -File .\Scripts\UnitTests\Invoke-ToolkitRtlScreenshot.ps1 (hosts RTLControlsTest; --rtl launches with both flags). Captured locally as 2379-toolkit-rtl-ltr.png / 2379-toolkit-rtl-rtl.png.

Screenshots / GIFs

Changelog

• Entry added to Documents/Changelog/Changelog.md:

* Implemented [#2379](https://github.com/Krypton-Suite/Standard-Toolkit/issues/2379), RTL support for **all** `Krypton.Toolkit` controls
  * Set `RightToLeft` and `RightToLeftLayout` on the host `KryptonForm` (or on the control). Both flags together mirror docks, splitters, group/header captions, spin buttons, and list reading order; `RightToLeft` alone still controls text Near/Far.
  * Context menus copy both flags onto the popup; submenus open toward the start edge; CommandLink arrows and TaskDialog table columns mirror when both flags are set. `KryptonPropertyGrid` forwards `RightToLeft` to the inner WinForms grid.

Breaking changes & migration

None. RightToLeftLayout is additive on Toolkit visual bases. KryptonDateTimePicker / KryptonTreeView / KryptonListView keep the same public property name (now inherited, with inner native sync). KryptonRibbon.RightToLeftLayout is an override of the Toolkit base property.

Developer documentation

• Documents/Development/Krypton-Toolkit-Rtl.md

Checklist

• Builds for net472 and is C# 7.3 compatible where required
• New compiler/analyzer warnings in touched code addressed
• Documents/Changelog/Changelog.md updated
• TestForm demo added or updated (features / observable bug fixes)
• Documents/Development/ guide added (substantial features)
• Screenshots/GIFs included (UI changes)
• Breaking-change impact and TFM notes documented above