Working with styles

First of all, let us call to mind, what “style”, “set of styles” and “library of styles” are.

Style is an element, which possesses a name and properties, and determines design attributes, i.e. color, font and frame. The style determines the way a report object should be designed. The objects such as TfrxMemoView have the Style property, which is a property intended to set the style name. When applying a value to this property, the style design attributes are copied to the object.

A set of styles consists of several styles, which refer to a report. The TfrxReport component has the Styles property, which refers to the object of the TfrxStyles type. The set of styles also possesses a name. The set of styles determines design of a whole report.

A styles library includes several sets of styles. It is convenient to perform a selection of a concrete set for report design with the help of the library.

The TfrxStyleItem represents a style.

  TfrxStyleItem = class(TCollectionItem)
  public
    // Style name.
    property Name: String;

    // Background color.
    property Color: TColor;

    // Font.
    property Font: TFont;

    // Frame.
    property Frame: TfrxFrame;
  end;

The set of styles is represented by the TfrxStyles class. It comprises methods for performing such set operations as reading, saving, adding, deleting, as well as searching for a style. The set of styles file has FS3 extension by default.

  TfrxStyles = class(TCollection)
  public
    // Creates the styles set. One can specify “nil” instead of “AReport,” however in this case a user would be unable to use the “Apply” method.
    constructor Create(AReport: TfrxReport);

    // Adds a new style.
    function Add: TfrxStyleItem;

    // Returns the style with the given name.
    function Find(const Name: String): TfrxStyleItem;

    // Applies a set to a report.
    procedure Apply;

    // Returns the list of the styles names.
    procedure GetList(List: TStrings);

    // Reads a set.
    procedure LoadFromFile(const FileName: String);
    procedure LoadFromStream(Stream: TStream);

    // Saves a set.
    procedure SaveToFile(const FileName: String);
    procedure SaveToStream(Stream: TStream);

    // The list of styles.
    property Items[Index: Integer]: TfrxStyleItem; default;

    // A set’s name.
    property Name: String;
  end;

In conclusion, the last TfrxStyleSheet class represents a styles’ library. It has methods for the library reading/saving, as well as adding, deleting, and style sets’ searching.

  TfrxStyleSheet = class(TObject)
  public
   // Constructs a library.
    constructor Create;

   // Clears a library.
    procedure Clear;

   // Deletes a set with certain number.
    procedure Delete(Index: Integer);

   // Returns the list of the names of styles’ sets.
    procedure GetList(List: TStrings);

   // Loads a library.
    procedure LoadFromFile(const FileName: String);
    procedure LoadFromStream(Stream: TStream);

   // Saves a library.
    procedure SaveToFile(const FileName: String);
    procedure SaveToStream(Stream: TStream);

   // Adds a new set of styles to the library.
    function Add: TfrxStyles;

   // Returns a number of styles’ sets in the library.
    function Count: Integer;

   // Returns a set with the given name.
    function Find(const Name: String): TfrxStyles;

   // Returns a set number with the given name.
    function IndexOf(const Name: String): Integer;

   // The list of styles’ sets.
    property Items[Index: Integer]: TfrxStyles; default;
  end;