Componentes.Terceros.TRichView/12.0.4/Demos/Addins/ComboItem/ComboItem.pas

{*******************************************************}
{                                                       }
{       RichView                                        }
{       Combo Item - item class for RichView.           }
{       Non-text item that looks like a text            }
{       (but cannot be wrapped and edited)              }
{       and shows combobox when focused.                }
{       Does not support Unicode.                       }
{       Shows combobox only in TRichView,               }
{       not in TRichViewEdit                            }
{                                                       }
{       Copyright (c) Sergey Tkachenko                  }
{       svt@trichview.com                               }
{       http://www.trichview.com                        }
{                                                       }
{*******************************************************}

unit ComboItem;

{$I RV_Defs.inc}

interface
uses {$IFDEF RICHVIEWDEF2009}AnsiStrings,{$ENDIF}
     Windows, SysUtils, Graphics, Classes, Controls, StdCtrls,
     RVItem, CRVData, CRVFData, RVStyle, RVScroll, RVFMisc,
     RVLabelItem, RVTypes;

const
  rvsCombo = -201;

type
  TRVComboItemInfo = class (TRVLabelItemInfo)
  private
    FItems: TStringList;
    FComboBox: TComboBox;
    FRVData: TCustomRVData;
    function GetItems: TStrings;
    procedure SetItems(const Value: TStrings);
    procedure DoComboBoxClick(Sender: TObject);
  protected
    function GetRVFExtraPropertyCount: Integer; override;
    procedure SaveRVFExtraProperties(Stream: TStream); override;
  public
    constructor Create(RVData: TPersistent); override;
    constructor CreateEx(RVData: TPersistent; TextStyleNo: Integer; const Text: String);
    destructor Destroy; override;
    function SetExtraCustomProperty(const PropName: TRVAnsiString;
        const Value: String): Boolean; override;
    function ReadRVFLine(const s: TRVRawByteString; RVData: TPersistent;
        ReadType, LineNo, LineCount: Integer; var Name: TRVRawByteString;
        var ReadMode: TRVFReadMode; var ReadState: TRVFReadState;
        UTF8Strings: Boolean; var AssStyleNameUsed: Boolean): Boolean; override;
    function GetBoolValueEx(Prop: TRVItemBoolPropertyEx; RVStyle: TRVStyle): Boolean; override;
    function GetBoolValue(Prop: TRVItemBoolProperty): Boolean; override;
    procedure Focusing; override;
    procedure ClearFocus; override;
    procedure Inserting(RVData: TObject; var Text: TRVRawByteString; Safe: Boolean); override;
    function OwnsControl(AControl: TControl): Boolean; override;
    procedure AdjustInserted(x,y: Integer; adjusty: Boolean); override;
    property Items: TStrings read GetItems write SetItems;
  end;

implementation

{============================== TRVComboItemInfo ==============================}
constructor TRVComboItemInfo.Create(RVData: TPersistent);
begin
  inherited;
  StyleNo := rvsCombo;
  Spacing := 0;
end;
{------------------------------------------------------------------------------}
constructor TRVComboItemInfo.CreateEx(RVData: TPersistent;
  TextStyleNo: Integer; const Text: String);
begin
  inherited CreateEx(RVData, TextStyleNo, Text);
  StyleNo := rvsCombo;
  Spacing := 0;
end;
{------------------------------------------------------------------------------}
destructor TRVComboItemInfo.Destroy;
begin
  FItems.Free;
  ClearFocus;
  inherited;
end;
{------------------------------------------------------------------------------}
procedure TRVComboItemInfo.ClearFocus;
var ComboBox: TComboBox;
begin
  ComboBox := FComboBox;
  FComboBox := nil;
  ComboBox.Free;
end;
{------------------------------------------------------------------------------}
procedure TRVComboItemInfo.Focusing;
var ItemNo, DItemNo: Integer;
begin
  ClearFocus;
  if FRVData<>nil then begin
    FComboBox := TComboBox.Create(nil);
    FComboBox.Visible := False;
    FComboBox.Parent := FRVData.GetParentControl;
    ItemNo := FRVData.GetItemNo(Self);
    TCustomRVFormattedData(FRVData).Item2FirstDrawItem(ItemNo, DItemNo);
    with TCustomRVFormattedData(FRVData).DrawItems[DItemNo] do begin
      FComboBox.Width := Width{+GetSystemMetrics(SM_CXVSCROLL)};
      FComboBox.Height := Height;
      FComboBox.Font.Assign(FRVData.GetRVStyle.TextStyles[TextStyleNo]);
      if FRVData.GetRVStyle.TextStyles[TextStyleNo].BackColor<>clNone then
        FComboBox.Color := FRVData.GetRVStyle.TextStyles[TextStyleNo].BackColor;
      FComboBox.Style := csDropDownList;
      FComboBox.Items := Items;
      FComboBox.ItemIndex := FComboBox.Items.IndexOf(Text);
      FComboBox.OnClick := DoComboBoxClick;
      TCustomRVFormattedData(FRVData).ResetSubCoords;
      AdjustInserted(Left-TCustomRVFormattedData(FRVData).GetHOffs,
        Top-TCustomRVFormattedData(FRVData).GetVOffs, True);
    end;
    FComboBox.Visible := True;
    FComboBox.SetFocus;
  end;
end;
{------------------------------------------------------------------------------}
function TRVComboItemInfo.GetBoolValueEx(Prop: TRVItemBoolPropertyEx;
  RVStyle: TRVStyle): Boolean;
begin
  case Prop of
    rvbpAllowsFocus:
      Result := True;
    rvbpXORFocus:
      Result := False;
    else
      Result := inherited GetBoolValueEx(Prop, RVStyle);
  end;
end;
{------------------------------------------------------------------------------}
function TRVComboItemInfo.GetBoolValue(Prop: TRVItemBoolProperty): Boolean;
begin
  case Prop of
   rvbpImmediateControlOwner:
     Result := FComboBox<>nil;
   else
     Result := inherited GetBoolValue(Prop);
  end;
end;
{------------------------------------------------------------------------------}
function TRVComboItemInfo.GetItems: TStrings;
begin
  if FItems=nil then
    FItems := TStringList.Create;
  Result := FItems;
end;
{------------------------------------------------------------------------------}
procedure TRVComboItemInfo.SetItems(const Value: TStrings);
begin
  FItems.Assign(Value);
end;
{------------------------------------------------------------------------------}
procedure TRVComboItemInfo.Inserting(RVData: TObject; var Text: TRVRawByteString;
  Safe: Boolean);
begin
  FRVData := TCustomRVData(RVData);
  if FComboBox<>nil then begin
    FComboBox.Visible := False;
    if not Safe and (RVData<>nil) then
      FComboBox.Parent := FRVData.GetParentControl
    else
      FComboBox.Parent := nil;
  end;
  inherited Inserting(RVData, Text, Safe);
end;
{------------------------------------------------------------------------------}
function TRVComboItemInfo.OwnsControl(AControl: TControl): Boolean;
begin
  Result := AControl=FComboBox;
end;
{------------------------------------------------------------------------------}
procedure TRVComboItemInfo.AdjustInserted(x, y: Integer; adjusty: Boolean);
begin
  if FComboBox<>nil then begin
    FComboBox.Left := x+Spacing;
    FComboBox.Tag  := y+Spacing;
    if adjusty then
      RV_Tag2Y(FComboBox);
    FComboBox.Visible := True;
  end;
end;
{------------------------------------------------------------------------------}
procedure TRVComboItemInfo.DoComboBoxClick(Sender: TObject);
begin
  if FComboBox.ItemIndex>=0 then begin
    Text := FComboBox.Text;
    UpdateMe;
  end;
end;
{------------------------------------------------------------------------------}
function TRVComboItemInfo.GetRVFExtraPropertyCount: Integer;
begin
  Result := Items.Count + inherited GetRVFExtraPropertyCount;
end;
{------------------------------------------------------------------------------}
procedure TRVComboItemInfo.SaveRVFExtraProperties(Stream: TStream);
var i: Integer;
begin
  inherited SaveRVFExtraProperties(Stream);
  for i := 0 to items.Count-1 do
    RVFWriteLine(Stream, {$IFDEF RVUNICODESTR}AnsiStrings.{$ENDIF}
      Format('item=%s', [StringToRVFString(Items[i])]));
end;
{------------------------------------------------------------------------------}
function TRVComboItemInfo.SetExtraCustomProperty(const PropName: TRVAnsiString;
  const Value: String): Boolean;
begin
  if PropName='item' then begin
    Items.Add(Value);
    Result := True;
    end
  else
    Result := inherited SetExtraCustomProperty(PropName, Value);
end;
{------------------------------------------------------------------------------}
function TRVComboItemInfo.ReadRVFLine(const s: TRVRawByteString; RVData: TPersistent;
        ReadType, LineNo, LineCount: Integer; var Name: TRVRawByteString;
        var ReadMode: TRVFReadMode; var ReadState: TRVFReadState;
        UTF8Strings: Boolean; var AssStyleNameUsed: Boolean): Boolean;
begin
  if LineNo=0 then
    Items.Clear;
  Result := inherited ReadRVFLine(s, RVData, ReadType, LineNo, LineCount, Name,
    ReadMode, ReadState, UTF8Strings, AssStyleNameUsed);
end;

initialization

  RegisterRichViewItemClass(rvsCombo, TRVComboItemInfo);

end.