DesignKit Package

DesignKit is a Lazarus package that provides a set of visual and non‑visual components to enhance application UI design.
All components are installed on the Common Controls tab of the component palette.

Requirements

• Lazarus (tested with 4.8) / Free Pascal Compiler 3.2.2 or newer.
• LCL – included with Lazarus.
• IDEIntf – included with Lazarus.
• RichMemoPackage – extended TRichMemo component with clipboard and undo helpers (available in the plainlib repository).
• Helpers – common utility units used by the spell‑checker (also available in plainlib).
• Toolkit – general‑purpose utility classes (available in plainlib).
• RichKit – additional rich‑text utilities (available in plainlib).
• Windows 8 or later is required only for the native WinSpellChecker backend. The HunSpell backend works on all platforms (Windows, Linux, macOS) and does not need any OS‑specific API.

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TSpellChecker (Common Controls )

TSpellChecker is a non‑visual component that adds spell‑checking capabilities to a TRichMemo control. It supports both the native Windows Spell Checker (on Windows) and Hunspell (cross‑platform), with background checking, real‑time debounced updates, cancellation, and an automatic context menu with suggestions.

Features

• Background spell checking with cancellation support.
• Debounced real‑time checking (configurable delay).
• Automatic application of error underlines (with AutoApply).
• Built‑in context menu with spelling suggestions (replaces the word when a suggestion is chosen).
• Integration with an external PopupMenu – suggestions can be placed directly in the menu or inside a submenu.
• Supports Windows Spell Checker (seWindows) and Hunspell (seHunspell).
• For Hunspell: loads dictionaries from files, streams, or automatically downloads them from a URL (LibreOffice dictionaries repository).
• Events: OnSpellCheckComplete (reports error count), OnContextPopup (allows custom handling).

Key Properties

Property	Default	Description
RichMemo	nil	The TRichMemo control to be spell‑checked.
Language	''	BCP‑47 language tag (e.g. 'en-US', 'ru-RU').
Enabled	True	Enables/disables spell checking.
Options	[scoSpelling]	Set of TSpellCheckOptions (scoSpelling, scoComprehensive – Windows only).
AddEmptySuggestions	True	Include errors even if no suggestions are available.
RealTime	False	Automatically check after text changes (with debounce).
CheckDelay	1000	Debounce delay in milliseconds for real‑time checks.
AutoApply	True	Automatically apply underlines after a check completes.
AutoContextMenu	True	Automatically handle OnContextPopup to show suggestion menu.
PopupMenu	nil	An external TPopupMenu to integrate suggestions into (if nil, uses default behaviour).
SubMenu	False	If True, suggestions are placed in a submenu.
SubMenuCaption	'Suggestions'	Caption of the submenu when SubMenu is True.
SubMenuIndex	0	Index where suggestions (or submenu) are inserted in PopupMenu.
Engine	seWindows	Spell engine: seWindows or seHunspell.
DicPath	''	Directory for Hunspell dictionaries (absolute or relative to the application).
DicUrl	'https://raw.githubusercontent.com/LibreOffice/dictionaries/master/{libredict}'	URL template for downloading dictionaries. Placeholders: {dict} (language code + .aff/.dic) or {libredict} (LibreOffice internal path).

Events

Event	Description
OnSpellCheckComplete	Fired after a check finishes (and after underlines are applied, if AutoApply is True). Provides the number of errors found.
OnContextPopup	Called before the component’s built‑in context menu handling. Set Handled to True to prevent the component from showing its menu.

Usage

1. Place a TSpellChecker on a form.
2. Assign its RichMemo property to a TRichMemo control.
3. Set the Language property (e.g. 'en-US').
4. Optionally set RealTime := True to enable live checking.
5. At runtime, the component will automatically check the text and underline errors. Right‑click on a misspelled word to see suggestions.

Example for Hunspell with automatic download:

var
  Spell: TSpellChecker;
begin
  Spell := TSpellChecker.Create(Self);
  Spell.RichMemo := RichMemo1;
  Spell.Language := 'ru-RU';
  Spell.Engine := seHunspell;
  Spell.DicPath := '.\dictionaries'; // local folder
  Spell.DicUrl := 'https://raw.githubusercontent.com/LibreOffice/dictionaries/master/{libredict}';
  Spell.RealTime := True;
  Spell.CheckDelay := 800;
  Spell.AutoApply := True;
end;

If you want to use a custom PopupMenu with suggestions inserted directly:

Spell.PopupMenu := MyPopupMenu;
Spell.SubMenu := False; // suggestions appear directly in the menu
Spell.SubMenuIndex := 2; // insert after the second item

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TFormGrip (Common Controls )

TFormGrip is a visual control that draws a size grip in a selected corner of its parent (a form or a panel) and resizes that parent when the grip is dragged. It behaves like the grip found in a StatusBar, but can be placed in any corner and styled freely.

The component does not hook or override any events of its parent. All mouse handling, painting, and resizing are performed inside the control itself, so the parent form's own OnPaint, OnMouseDown, OnMouseMove, OnMouseUp, and OnResize handlers remain untouched.

Features

• Works with any TWinControl parent, not only with forms.
• Grip can be placed in any of the four corners of the parent.
• The control automatically snaps to the chosen corner and cannot be moved away from it; resizing or repositioning the parent keeps the grip in place.
• Multiple grip drawing styles: dots (triangular arrangement), lines, grid, or solid triangle.
• Background can either follow the parent colour (ParentColor = True, the default) or use its own Color.
• Two independent offsets, named after the CSS box model: GripMargin moves the whole control away from the parent corner, while GripPadding insets the drawn pattern inside the control.
• Resizing respects configurable minimum parent width and height.
• Double buffered painting with csOpaque, so the grip redraws cleanly during parent resize without flicker or black artefacts.
• In design time the grip is drawn but does not resize the parent.

Key Properties

Property	Default	Description
Visible	True	Shows or hides the grip.
ShowGrip	True	Controls drawing of the grip pattern.
GripCorner	gcBottomRight	Corner of the parent: gcBottomRight, gcBottomLeft, gcTopRight, or gcTopLeft.
GripMargin	0	Outer offset - distance between the control and the parent's corner (in pixels).
GripPadding	2	Inner offset - distance between the control's edge and the drawn pattern (in pixels).
GripColor	clActiveBorder	Colour used to draw the grip pattern.
GripStyle	gsDots	Drawing style: gsDots, gsLines, gsGrid, or gsSolid.
DotSize	2	Size of the dots (for gsDots and gsGrid).
DotSpacing	3	Distance between dots.
MinParentWidth	100	Minimum parent width allowed during resizing.
MinParentHeight	100	Minimum parent height allowed during resizing.
ParentColor	True	When True, background follows Parent.Color; otherwise uses Color.
Color	clBtnFace	Background colour used when ParentColor is False.
Width, Height	16, 16	Size of the grip control in pixels.

Usage

1. Drop a TFormGrip component from the Common Controls palette onto a form or a panel.
2. Choose the desired corner using GripCorner and adjust the remaining properties in the Object Inspector.
3. At runtime the grip appears in the selected corner and resizes its parent when dragged.

Example code to create and configure TFormGrip at runtime:

var
  Grip: TFormGrip;
begin
  Grip := TFormGrip.Create(Self); // Self is the parent control
  Grip.Parent := Self;
  Grip.GripCorner := gcBottomRight;
  Grip.GripStyle := gsLines;
  Grip.GripColor := clGray;
  Grip.GripMargin := 0;
  Grip.GripPadding := 3;
  Grip.Width := 16;
  Grip.Height := 16;
end;

Class hierarchy

The component is split into two classes following the standard Lazarus convention:

• TCustomFormGrip - base class that implements all behaviour. Inherit from it to create custom variants with your own published properties.
• TFormGrip - ready-to-use component that publishes the most useful properties of TCustomFormGrip and of the inherited TControl.

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TFlatButton (Common Controls )

TFlatButton is a custom TSpeedButton descendant that always draws a flat, themed button (similar to toolbar buttons) and provides integrated tooltip support with extensive customisation.

Features

• Always flat (inherited Flat property is hidden and forced to True).
• Uses the native theme (via ThemeServices) for normal, hot, and pressed states.
• Can optionally disable the pressed state drawing (DrawPressed).
• Allows vertical offset of the caption relative to the icon (OffsetY).
• Built‑in tooltip system with delay, size, colour, and auto‑hide duration.
• Tooltips are displayed using TOneShotTooltip and automatically hide when the button is clicked or the tooltip is dismissed.

Key Properties

Property	Default	Description
DrawPressed	True	If False, the button never appears pressed (visual state is always normal or hot).
OffsetY	0	Vertical pixel offset for the caption relative to the centre of the icon (positive moves text down).
Tooltip	''	The tooltip text to display (translatable caption).
TooltipDelay	0	Delay in milliseconds before the tooltip appears after a click (0 = immediate).
TooltipWidth	0	Width of the tooltip window (0 = auto‑size).
TooltipHeight	0	Height of the tooltip window (0 = auto‑size).
TooltipColor	clDefault	Background colour of the tooltip (clDefault uses system default).
TooltipDuration	0	Time in milliseconds after which the tooltip auto‑hides (0 = no auto‑hide).

Usage

Place a TFlatButton on a form, set an Images or Glyph for the icon, adjust Caption, and configure the tooltip properties.

Example:

var
  Btn: TFlatButton;
begin
  Btn := TFlatButton.Create(Self);
  Btn.Parent := Self;
  Btn.Caption := 'Save';
  Btn.ImageIndex := 0; // assume an ImageList assigned
  Btn.Tooltip := 'Save the current document';
  Btn.TooltipDelay := 500;
  Btn.TooltipDuration := 3000;
  Btn.OffsetY := 2; // move text slightly down
end;

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Installation

1. Open the package file (designkit.lpk) in Lazarus.
2. Click Use → Install.
3. Rebuild the IDE.

The components will appear on the Common Controls tab of the component palette.

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DesignKit Package © 2026 by Alexander Tverskoy
Licensed under the MIT License – see the individual source files for details.