lazarus/lcl/interfaces/gtk2/gtk2themes.pas

unit Gtk2Themes;

{$mode objfpc}{$H+}

interface

uses
  // rtl
  Types, Classes, SysUtils,
  // os
  glib2,  gdk2, gtk2, Pango,
  // lcl
  LCLType, LCLProc, LCLIntf, Graphics, Themes, TmSchema,
  // widgetset
  GtkDef, Gtk2Int, GtkProc, GtkThemes, GtkGlobals;
  
type
  { TGtk2ThemeServices }

  TGtk2ThemeServices = class(TGtkThemeServices)
  protected
    function GetGtkStyleParams(DC: HDC; Details: TThemedElementDetails; AIndex: Integer): TGtkStyleParams; override;
  public
    function GetDetailSize(Details: TThemedElementDetails): Integer; override;
  end;

implementation

function GetColumnButtonFromTreeView(AWidget: PGtkWidget): PGtkWidget;
var
  AColumn: PGtkTreeViewColumn;
begin
  Result := nil;
  if not GTK_IS_TREE_VIEW(AWidget) then
    exit;

  AColumn := gtk_tree_view_get_column(PGtkTreeView(AWidget), 0);
  if AColumn = nil then
    Exit;
  Result := AColumn^.button;
end;

{ TGtk2ThemeServices }

function TGtk2ThemeServices.GetGtkStyleParams(DC: HDC;
  Details: TThemedElementDetails; AIndex: Integer): TGtkStyleParams;
begin
  Result := inherited GetGtkStyleParams(DC, Details, AIndex);
  
  // override some styles
  if Result.Style <> nil then
    case Details.Element of
      teHeader:
        begin
          Result.Widget := GetColumnButtonFromTreeView(GetStyleWidget(lgsTreeView));
          if Result.Widget = nil then
            Result.Widget := GetStyleWidget(lgsTreeView);
          Result.State := GtkButtonMap[Details.State];
          if Details.State = PBS_PRESSED then
            Result.Shadow := GTK_SHADOW_IN
          else
            Result.Shadow := GTK_SHADOW_OUT;

          Result.IsHot:= Result.State = GTK_STATE_PRELIGHT;

          Result.Detail := 'button';
          Result.Painter := gptBox;
        end;
      teRebar:
        begin
          case Details.Part of
            RP_GRIPPER, RP_GRIPPERVERT:
              begin
                Result.State := GTK_STATE_NORMAL;
                Result.Shadow := GTK_SHADOW_NONE;
                Result.Detail := 'paned';
                Result.Painter := gptHandle;
                if Details.Part = RP_GRIPPER then
                begin
                  Result.Orientation := GTK_ORIENTATION_VERTICAL;
                  Result.Widget := GetStyleWidget(lgsVerticalPaned);
                end
                else
                begin
                  Result.Orientation := GTK_ORIENTATION_HORIZONTAL;
                  Result.Widget := GetStyleWidget(lgsHorizontalPaned);
                end;
              end;
            RP_BAND:
              begin
                Result.Widget := GetStyleWidget(lgsVerticalPaned);
                Result.State := GtkButtonMap[Details.State];
                Result.Shadow := GTK_SHADOW_NONE;
                Result.Detail := 'paned';
                Result.Painter := gptFlatBox;
              end;
          end;
        end;
      teTreeview:
        begin
          if Details.Part = TVP_GLYPH then
          begin
            Result.Painter := gptExpander;
            Result.Shadow := GTK_SHADOW_NONE;
            Result.State := GTK_STATE_NORMAL;
            Result.Widget := GetStyleWidget(lgsTreeView);
            Result.Detail := 'treeview';
            if Details.State = GLPS_CLOSED then
              Result.Expander := GTK_EXPANDER_COLLAPSED
            else
              Result.Expander := GTK_EXPANDER_EXPANDED;

            Result.ExpanderSize := GetDetailSize(Details);
          end;
        end;
    end;
end;

function TGtk2ThemeServices.GetDetailSize(Details: TThemedElementDetails): Integer;
var
  AValue: TGValue;
begin
  if (Details.Element = teTreeView) and (Details.Part = TVP_GLYPH) then
  begin
    FillChar(AValue, SizeOf(AValue), 0);
    g_value_init(@AValue, G_TYPE_INT);
    gtk_widget_style_get_property(GetStyleWidget(lgsTreeView), 'expander-size', @AValue);
    Result := AValue.data[0].v_int;
  end
  else
    Result := GetBaseDetailsSize(Details);
end;

end.