DelphiColorPreview

A lightweight RAD Studio (Delphi 12 Athens) IDE plugin that shows a color swatch in the editor gutter next to every color literal in your source — like the color decorators in VS Code — and lets you Shift+click a swatch to pick a new color, rewriting the literal directly in your code.

Features

• Color swatches in the left gutter, on every line that contains a color literal.

• Recognizes three Delphi color forms:

  Form	Example	Notes
  clXXX	clRed, clBtnFace	VCL named constants; system colors resolved to their real RGB
  $00BBGGRR	$00FF8040	TColor hex (BGR byte order); 6–8 hex digits
  RGB(r,g,b)	RGB(255, 128, 0)	integer-literal arguments only

• Edit colors straight from the gutter (see Usage).

• No configuration, no toolbar, no menu — build, install, done.

Requirements

• RAD Studio 12 Athens (Delphi, compiler 36.0 / package version 290).
• Win32 design-time package (the IDE host is a 32-bit process).

Installation

1. Open DelphiColorPreview.dproj in RAD Studio 12.
2. Build the project.
3. Right-click the project in the Project Manager → Install.

That's it — the swatches show up in the editor gutter immediately. To uninstall, right-click the project → Uninstall (or remove it from Component → Install Packages…).

Prefer the command line? Run build.bat (it calls rsvars.bat + msbuild, Win32 / Debug) and then do step 3 in the IDE.

Usage

• A color swatch appears in the gutter next to every line that has a color literal — with or without a breakpoint on that line.
• Shift+click a swatch to open a color picker. Choosing a color rewrites the literal in your code, keeping the original form:
  • $00BBGGRR stays a hex literal,
  • RGB(r, g, b) stays an RGB() call,
  • clXXX becomes the matching named constant when one exists (otherwise a hex literal).
• The edit goes through the editor buffer, so Ctrl+Z undoes it like any other change.
• A plain (non-Shift) click is left untouched, so the gutter still works for breakpoints.

How it works

The package registers a single global INTACodeEditorEvents notifier through (BorlandIDEServices as INTACodeEditorServices).AddEditorEventsNotifier.

• Swatches are painted at the pgsEndPaint gutter stage, which runs once after the whole gutter is drawn with a clip covering the entire gutter. The plugin enumerates the visible lines (EditorState.TopLine..BottomLine → LineState[]) and draws a swatch in each line's GutterRect. Using the line's own gutter rectangle means there is no column-to-pixel math, so the swatch never drifts.
• Line text and geometry come straight from INTACodeEditorLineState (.Text, .GutterRect).
• Editing goes through IOTAEditView.Buffer.EditPosition (Move / Delete / InsertText) so the IDE records a normal, undoable edit.

Source layout

File	Responsibility
ColorPreview.Parser.pas	FindColorTokens — scans one line into color tokens
ColorPreview.Notifier.pas	TColorPreviewNotifier — paints swatches, handles the click
ColorPreview.Register.pas	registers / unregisters the notifier on package load
DelphiColorPreview.dpk	the design-only package (requires rtl, vcl, designide)

License

MIT