TSVGIconImageCollection

Unit: SVGIconImageCollection

Inherits from: TCustomImageCollection (Delphi 10.3+) or TComponent

Minimum Delphi Version: 10.3 Rio (for full VirtualImageList integration)

Description

TSVGIconImageCollection is a modern VCL component for storing and managing collections of SVG icons. It follows Delphi's ImageCollection/VirtualImageList architecture introduced in Delphi 10.3, allowing multiple TSVGIconVirtualImageList components to share the same icon source at different sizes.

Unlike TSVGIconImageList which contains both storage and rendering, TSVGIconImageCollection only stores SVG icons. Rendering is performed by linked TSVGIconVirtualImageList components, enabling efficient memory usage when the same icons are needed at multiple sizes.

Published Properties

Icon Collection

SVGIconItems

property SVGIconItems: TSVGIconItems;

Collection of SVG icon items. Each item contains an SVG image and associated properties.

Usage:

// Access items
var Item := SVGIconImageCollection1.SVGIconItems[0];

// Count
Label1.Caption := Format('%d icons', [SVGIconImageCollection1.SVGIconItems.Count]);

Default Rendering Attributes

These properties set default rendering attributes for all icons. Individual icons can override these settings.

FixedColor

property FixedColor: TColor;

Default fixed color for all icons. Default: SVG_INHERIT_COLOR

Usage:

SVGIconImageCollection1.FixedColor := clBlue;

ApplyFixedColorToRootOnly

property ApplyFixedColorToRootOnly: Boolean;

Apply FixedColor only to root SVG elements. Default: False

Usage:

SVGIconImageCollection1.FixedColor := clRed;
SVGIconImageCollection1.ApplyFixedColorToRootOnly := True;

GrayScale

property GrayScale: Boolean;

Render all icons in grayscale. Default: False

Usage:

SVGIconImageCollection1.GrayScale := True;

Opacity

property Opacity: Byte;

Default opacity for all icons (0-255). Default: 255

Usage:

SVGIconImageCollection1.Opacity := 200;

AntiAliasColor

property AntiAliasColor: TColor;

Background color for anti-aliasing. Default: clBtnFace

Usage:

SVGIconImageCollection1.AntiAliasColor := clWhite;

Public Methods

Create / Destroy

constructor Create(AOwner: TComponent);
destructor Destroy; override;

Icon Management

Add

function Add(const ASVG: ISVG; const AIconName: string;
  const AGrayScale: Boolean = False;
  const AFixedColor: TColor = SVG_INHERIT_COLOR;
  const AApplyToRootOnly: Boolean = False): Integer;

Adds a new SVG icon to the collection and returns its index.

Parameters:

• ASVG: SVG interface to add
• AIconName: Name for the icon
• AGrayScale: Render this icon in grayscale
• AFixedColor: Fixed color for this icon
• AApplyToRootOnly: Apply fixed color only to root element

Returns: Index of the newly added icon

Usage:

var
  SVG: ISVG;
  Index: Integer;
begin
  SVG := GlobalSVGFactory.NewSvg;
  SVG.LoadFromFile('home.svg');
  Index := SVGIconImageCollection1.Add(SVG, 'home');
end;

Delete

procedure Delete(const Index: Integer);

Deletes the icon at the specified index.

Usage:

SVGIconImageCollection1.Delete(0);

Delete (range with optional category filter)

procedure Delete(const ACategory: String; AStartIndex, AEndIndex: Integer);

Deletes a range of icons, optionally filtered by category.

Parameters:

• ACategory: Category to filter (empty string = all categories)
• AStartIndex: Starting index (inclusive)
• AEndIndex: Ending index (inclusive)

Usage:

// Delete icons 5-10
SVGIconImageCollection1.Delete('', 5, 10);

// Delete icons 0-4 in 'Navigation' category
SVGIconImageCollection1.Delete('Navigation', 0, 4);

Remove

procedure Remove(const Name: string);

Removes the icon with the specified name.

Usage:

SVGIconImageCollection1.Remove('home');
SVGIconImageCollection1.Remove('Navigation\home');

IndexOf

function IndexOf(const Name: string): Integer;

Returns the index of the named icon, or -1 if not found.

Usage:

var
  Index: Integer;
begin
  Index := SVGIconImageCollection1.IndexOf('settings');
  if Index >= 0 then
    ShowMessage('Found at index: ' + IntToStr(Index));
end;

ClearIcons

procedure ClearIcons;

Removes all icons from the collection.

Usage:

SVGIconImageCollection1.ClearIcons;

File Operations

LoadFromFile

function LoadFromFile(const AFileName: string; out AImageName: string): TSVGIconItem;

Loads an SVG from a file and returns the created item.

Parameters:

• AFileName: Path to SVG file
• AImageName: Receives the name of the loaded icon (filename without extension)

Returns: The newly created TSVGIconItem

Usage:

var
  Item: TSVGIconItem;
  ImageName: string;
begin
  Item := SVGIconImageCollection1.LoadFromFile('C:\Icons\home.svg', ImageName);
  ShowMessage('Loaded as: ' + ImageName);
end;

LoadFromFiles

function LoadFromFiles(const AFileNames: TStrings; const AAppend: Boolean = True): Integer;

Loads multiple SVG files and returns the count loaded.

Parameters:

• AFileNames: List of file paths
• AAppend: If True, append to existing icons; if False, clear first

Returns: Number of icons successfully loaded

Usage:

var
  Files: TStringList;
  Count: Integer;
begin
  Files := TStringList.Create;
  try
    Files.LoadFromFile('iconlist.txt');
    Count := SVGIconImageCollection1.LoadFromFiles(Files, True);
    ShowMessage(Format('Loaded %d icons', [Count]));
  finally
    Files.Free;
  end;
end;

SaveToFile

function SaveToFile(const AFileName: string; const AImageName: string): Boolean;

Saves a named icon to a file.

Parameters:

• AFileName: Target file path
• AImageName: Name of the icon to save

Returns: True if successful

Usage:

if SVGIconImageCollection1.SaveToFile('C:\Export\home.svg', 'home') then
  ShowMessage('Icon saved successfully');

Resource Operations

LoadFromResource

function LoadFromResource(const hInstance: THandle;
  const ResourceName: string; const IconName: string): Integer;

Loads an SVG from a compiled resource.

Parameters:

• hInstance: Module handle (use HInstance for current executable)
• ResourceName: Name of the resource
• IconName: Name to assign to the loaded icon

Returns: Index of the loaded icon

Usage:

// Add SVG to resources first (.rc file):
// HOME_ICON SVG "home.svg"

Index := SVGIconImageCollection1.LoadFromResource(HInstance, 'HOME_ICON', 'home');

LoadFromString

function LoadFromString(const Source: string; const IconName: string): Integer;

Loads an SVG from an XML string.

Parameters:

• Source: SVG XML content
• IconName: Name to assign to the icon

Returns: Index of the loaded icon

Usage:

const
  HomeSVG = '<svg width="24" height="24"><path d="M10 20v-6h4v6h5v-8h3L12 3 2 12h3v8z"/></svg>';
begin
  Index := SVGIconImageCollection1.LoadFromString(HomeSVG, 'home');
end;

Rendering Attributes

SetColors

procedure SetColors(const AFixedColor: TColor = SVG_INHERIT_COLOR;
  const AApplyToRootOnly: Boolean = False;
  const AAntiAliasColor: TColor = clBtnFace);

Sets color attributes for the entire collection.

Usage:

SVGIconImageCollection1.SetColors(clBlue, False, clWhite);

UpdateAttributes (Delphi 10.3+)

procedure UpdateAttributes(AFixedColor: TColor;
  AApplyFixedColorToRootOnly: Boolean; AGrayScale: Boolean;
  AAntiAliasColor: TColor; AOpacity: Byte);

Updates all rendering attributes at once.

Usage:

SVGIconImageCollection1.UpdateAttributes(
  clBlue,  // FixedColor
  False,   // ApplyToRootOnly
  False,   // GrayScale
  clWhite, // AntiAliasColor
  255      // Opacity
);

Access Methods (Delphi 10.3+)

IsIndexAvailable

function IsIndexAvailable(AIndex: Integer): Boolean;

Checks if an index is valid.

Usage:

if SVGIconImageCollection1.IsIndexAvailable(5) then
  ShowMessage('Index 5 exists');

GetIndexByName

function GetIndexByName(const AName: String): Integer;

Gets the index of a named icon.

Usage:

Index := SVGIconImageCollection1.GetIndexByName('home');

GetNameByIndex

function GetNameByIndex(AIndex: Integer): String;

Gets the name of an icon by index.

Usage:

Name := SVGIconImageCollection1.GetNameByIndex(0);

Drawing

Draw

procedure Draw(ACanvas: TCanvas; ARect: TRect; AIndex: Integer;
  AProportional: Boolean = False);

Draws an icon directly to a canvas.

Parameters:

• ACanvas: Target canvas
• ARect: Rectangle to draw in
• AIndex: Icon index
• AProportional: Maintain aspect ratio

Usage:

SVGIconImageCollection1.Draw(
  Canvas,
  Rect(10, 10, 74, 74),
  0,
  True
);

GetBitmap (Delphi 10.3+)

function GetBitmap(AIndex: Integer; AWidth, AHeight: Integer): TBitmap;

Returns a bitmap representation of an icon.

Parameters:

• AIndex: Icon index
• AWidth, AHeight: Desired bitmap size

Returns: New TBitmap instance (caller must free)

Usage:

var
  Bitmap: TBitmap;
begin
  Bitmap := SVGIconImageCollection1.GetBitmap(0, 48, 48);
  try
    Image1.Picture.Assign(Bitmap);
  finally
    Bitmap.Free;
  end;
end;

Miscellaneous

Assign

procedure Assign(Source: TPersistent); override;

Assigns content from another collection.

Usage:

SVGIconImageCollection2.Assign(SVGIconImageCollection1);

Examples

Basic Setup with Virtual ImageLists

procedure TForm1.FormCreate(Sender: TObject);
begin
  // Load icons into collection (once)
  var Files := TStringList.Create;
  try
    Files.Add('icons\home.svg');
    Files.Add('icons\settings.svg');
    Files.Add('icons\exit.svg');
    SVGIconImageCollection1.LoadFromFiles(Files);
  finally
    Files.Free;
  end;

  // Configure small icons (16x16)
  SVGIconVirtualImageListSmall.ImageCollection := SVGIconImageCollection1;
  SVGIconVirtualImageListSmall.Size := 16;

  // Configure large icons (48x48)
  SVGIconVirtualImageListLarge.ImageCollection := SVGIconImageCollection1;
  SVGIconVirtualImageListLarge.Size := 48;

  // Use with controls
  ToolBar1.Images := SVGIconVirtualImageListSmall;
  ListView1.LargeImages := SVGIconVirtualImageListLarge;

  // Same icons, different sizes, shared storage!
end;

Dynamic Icon Loading

procedure TForm1.Button1Click(Sender: TObject);
begin
  if OpenDialog1.Execute then
  begin
    var ImageName: string;
    SVGIconImageCollection1.LoadFromFile(OpenDialog1.FileName, ImageName);
    ListBox1.Items.Add(ImageName);
  end;
end;

Icon Organization with Categories

procedure TForm1.LoadCategorizedIcons;
var
  SVG: ISVG;
begin
  SVG := GlobalSVGFactory.NewSvg;

  // Navigation category
  SVG.LoadFromFile('home.svg');
  SVGIconImageCollection1.Add(SVG, 'home', 'Navigation');

  SVG.LoadFromFile('back.svg');
  SVGIconImageCollection1.Add(SVG, 'back', 'Navigation');

  // Actions category
  SVG.LoadFromFile('save.svg');
  SVGIconImageCollection1.Add(SVG, 'save', 'Actions');

  SVG.LoadFromFile('delete.svg');
  SVGIconImageCollection1.Add(SVG, 'delete', 'Actions');

  // Icons are named: Navigation\home, Navigation\back, Actions\save, Actions\delete
end;

Theme Support

procedure TForm1.ApplyTheme(ADarkMode: Boolean);
begin
  if ADarkMode then
  begin
    SVGIconImageCollection1.FixedColor := clWhite;
    SVGIconImageCollection1.AntiAliasColor := $202020;
  end
  else
  begin
    SVGIconImageCollection1.FixedColor := clBlack;
    SVGIconImageCollection1.AntiAliasColor := clWhite;
  end;

  // All linked virtual image lists automatically update
end;

Batch Icon Import

procedure TForm1.ImportIconsFromDirectory(const APath: string);
var
  Files: TStringList;
  SR: TSearchRec;
begin
  Files := TStringList.Create;
  try
    if FindFirst(TPath.Combine(APath, '*.svg'), faAnyFile, SR) = 0 then
    begin
      repeat
        Files.Add(TPath.Combine(APath, SR.Name));
      until FindNext(SR) <> 0;
      FindClose(SR);
    end;

    var Count := SVGIconImageCollection1.LoadFromFiles(Files, True);
    ShowMessage(Format('Imported %d icons', [Count]));
  finally
    Files.Free;
  end;
end;

Custom Drawing

procedure TForm1.PaintBox1Paint(Sender: TObject);
var
  R: TRect;
  I: Integer;
begin
  // Draw icon grid
  for I := 0 to SVGIconImageCollection1.SVGIconItems.Count - 1 do
  begin
    R := Rect(
      (I mod 4) * 64,
      (I div 4) * 64,
      (I mod 4) * 64 + 64,
      (I div 4) * 64 + 64
    );
    SVGIconImageCollection1.Draw(PaintBox1.Canvas, R, I, True);
  end;
end;

Export Collection

procedure TForm1.ExportAllIcons(const AOutputPath: string);
var
  I: Integer;
  IconName, FileName: string;
begin
  ForceDirectories(AOutputPath);

  for I := 0 to SVGIconImageCollection1.SVGIconItems.Count - 1 do
  begin
    IconName := SVGIconImageCollection1.GetNameByIndex(I);
    FileName := TPath.Combine(AOutputPath, IconName + '.svg');

    // Create subdirectories for categories
    ForceDirectories(ExtractFilePath(FileName));

    SVGIconImageCollection1.SaveToFile(FileName, IconName);
  end;

  ShowMessage(Format('Exported %d icons', [SVGIconImageCollection1.SVGIconItems.Count]));
end;

Notes

Benefits of ImageCollection Architecture

1. Memory Efficiency: Store icons once, render at multiple sizes
2. Centralized Management: Update all icon lists by changing the collection
3. Design-Time Preview: Visual editing in the IDE
4. Standard Integration: Works with VCL's Virtual ImageList system

Comparison with TSVGIconImageList

Feature	TSVGIconImageCollection	TSVGIconImageList
Storage	Yes	Yes
Rendering	No (via VirtualImageList)	Yes
Delphi Version	10.3+	XE6+
Multiple Sizes	Yes (efficient)	No (need separate lists)
Memory Usage	Lower (shared storage)	Higher (per list)
Complexity	Moderate (2 components)	Simple (1 component)

When to Use

Use TSVGIconImageCollection when:

• Using Delphi 10.3 or later
• Need same icons at multiple sizes
• Want centralized icon management
• Building modern applications

Use TSVGIconImageList when:

• Supporting older Delphi versions (XE6-10.2)
• Simple single-size icon lists
• Quick prototyping
• Legacy code migration

See Also

• TSVGIconVirtualImageList
• TSVGIconItems
• TSVGIconItem
• Virtual Image Collection Guide
• VCL Reference Overview