グリッドの列/行の選択に基づいて項目インデックスを決定する数学

Question

私と2人は、何が簡単な式であるべきかを把握しようとしています。私は、列と行の可変数を持つことができるグリッドを持っています。ユーザーがセルの1つをクリックすると、col/rowに基づいてクリックされた「インデックス」を特定する必要があります。インデックスは0から始まり、左から右、次に上から下に移動します。固定列/行はありません。私が言いたいの

サンプル：3列、およびC2/R1上のユーザーがクリックがある場合は

だから、それはすべてのインデックスが、この例では0から始まる5のインデックスを解決する必要があります。ここでは、

//I = Calculated index based on row/col (starts from 0) 
//ACol = Column index user clicked (starts from 0) 
//ARow = Row index user clicked (starts from 0) 
//ColCount = Number of columns 

I:= (C * ColCount) + (R - ColCount); 

---

EDIT参考

以下の私の全体の構成単位である：、遠くの作業からです

私の現在の式には、このようなものです。

式で行がコメント "HERE FORMULA" 以下の回答に

感謝を決議

unit ImageGrid; 

interface 

uses 
    Windows, Classes, SysUtils, Grids, Graphics, StdCtrls, ExtCtrls, Controls, 
    Jpeg, PngImage; 

type 
    TImageGrid = class; 
    TImageGridItem = class; 

    TGridSizing = (gsManual, gsAuto, gsFit); 

    TImageGridItem = class(TObject) 
    private 
    FFilename: TFilename; 
    FOwner: TImageGrid; 
    FBmp: TBitmap; 
    procedure Event; 
    procedure SetFilename(const Value: TFilename); 
    public 
    constructor Create(AOwner: TImageGrid); 
    destructor Destroy; override; 
    procedure LoadFile; 
    published 
    property Filename: TFilename read FFilename write SetFilename; 
    end; 

    TImageGrid = class(TCustomDrawGrid) 
    private 
    FItems: TStringList; 
    FCacheDir: String; 
    FRowHeight: Integer; 
    FColWidth: Integer; 
    FSizing: TGridSizing; 
    FItemIndex: Integer; 
    procedure SetCacheDir(const Value: String); 
    procedure SetColWidth(const Value: Integer); 
    procedure SetRowHeight(const Value: Integer); 
    procedure SetSizing(const Value: TGridSizing); 
    function GetItem(Index: Integer): TImageGridItem; 
    procedure SetItem(Index: Integer; const Value: TImageGridItem); 
    procedure SetItemIndex(const Value: Integer); 
    procedure SelectCell(Sender: TObject; ACol, ARow: Longint; 
     var CanSelect: Boolean); 
    protected 
    procedure Paint; override; 
    public 
    constructor Create(AOwner: TComponent); override; 
    destructor Destroy; override; 
    function Count: Integer; 
    property Items[Index: Integer]: TImageGridItem 
     read GetItem write SetItem; default; 
    function Add: TImageGridItem; 
    procedure Delete(const Index: Integer); 
    procedure Clear; 
    published 
    property CacheDir: String read FCacheDir write SetCacheDir; 
    property ColWidth: Integer read FColWidth write SetColWidth; 
    property RowHeight: Integer read FRowHeight write SetRowHeight; 
    property Sizing: TGridSizing read FSizing write SetSizing; 
    property ItemIndex: Integer read FItemIndex write SetItemIndex; 

    property Align; 
    property Anchors; 
    property BevelEdges; 
    property BevelInner; 
    property BevelKind; 
    property BevelOuter; 
    property BevelWidth; 
    property BiDiMode; 
    property BorderStyle; 
    property Color; 
    property ColCount; 
    property Constraints; 
    property Ctl3D; 
    property DefaultColWidth; 
    property DefaultRowHeight; 
    property DefaultDrawing; 
    property DoubleBuffered; 
    property DragCursor; 
    property DragKind; 
    property DragMode; 
    property DrawingStyle; 
    property Enabled; 
    property Font; 
    property GradientEndColor; 
    property GradientStartColor; 
    property GridLineWidth; 
    property Options; 
    property ParentBiDiMode; 
    property ParentColor; 
    property ParentCtl3D; 
    property ParentDoubleBuffered; 
    property ParentFont; 
    property ParentShowHint; 
    property PopupMenu; 
    property ScrollBars; 
    property ShowHint; 
    property TabOrder; 
    property Touch; 
    property Visible; 

    property OnClick; 
    property OnColumnMoved; 
    property OnContextPopup; 
    property OnDblClick; 
    property OnDragDrop; 
    property OnDragOver; 
    property OnDrawCell; 
    property OnEndDock; 
    property OnEndDrag; 
    property OnEnter; 
    property OnExit; 
    property OnGesture; 
    property OnGetEditMask; 
    property OnGetEditText; 
    property OnKeyDown; 
    property OnKeyPress; 
    property OnKeyUp; 
    property OnMouseActivate; 
    property OnMouseDown; 
    property OnMouseEnter; 
    property OnMouseLeave; 
    property OnMouseMove; 
    property OnMouseUp; 
    property OnMouseWheelDown; 
    property OnMouseWheelUp; 
    property OnRowMoved; 
    property OnSelectCell; 
    property OnSetEditText; 
    property OnStartDock; 
    property OnStartDrag; 
    property OnTopLeftChanged; 
    end; 

implementation 

//Register procedure will come later... 

{ TImageGrid } 

function TImageGrid.Add: TImageGridItem; 
begin 
    Result:= TImageGridItem.Create(Self); 
    FItems.AddObject('', Result); 
end; 

procedure TImageGrid.Clear; 
begin 
    while Count > 0 do 
    Delete(0); 
end; 

function TImageGrid.Count: Integer; 
begin 
    Result:= FItems.Count; 
end; 

constructor TImageGrid.Create(AOwner: TComponent); 
begin 
    inherited; 
    Options:= [goFixedVertLine,goFixedHorzLine,goVertLine,goHorzLine, 
    goRangeSelect,goThumbTracking]; 
    Parent:= TWinControl(AOwner); 
    FItems:= TStringList.Create; 
    FixedCols:= 0; 
    FixedRows:= 0; 
    RowCount:= 1; 
    ColCount:= 1; 
    FColWidth:= 100; 
    FRowHeight:= 100; 
    ColWidths[0]:= FColWidth; 
    RowHeights[0]:= FRowHeight; 
    FSizing:= gsManual; 
    FItemIndex:= -1; 
    OnSelectCell:= SelectCell; 

    Invalidate; 
end; 

procedure TImageGrid.Delete(const Index: Integer); 
begin 
    if (Index >= 0) and (Index < FItems.Count) then begin 
    TImageGridItem(FItems.Objects[Index]).Free; 
    FItems.Delete(Index); 
    end else begin 
    raise Exception.Create('List index out of bounds ('+IntToStr(Index)+')'); 
    end; 
end; 

destructor TImageGrid.Destroy; 
begin 
    FItems.Free; 
    inherited; 
end; 

function TImageGrid.GetItem(Index: Integer): TImageGridItem; 
begin 
    if (Index >= 0) and (Index < FItems.Count) then begin 
    Result:= TImageGridItem(FItems.Objects[Index]); 
    end else begin 
    Result:= nil; 
    raise Exception.Create('List index out of bounds ('+IntToStr(Index)+')'); 
    end; 
end; 

procedure TImageGrid.Paint; 
var 
    Bmp: TBitmap; 
    C: Integer; 
    RC: Integer; 
    CC: Integer; 
    X, Y: Integer; 
    I: TImageGridItem; 
    R: TRect; 

    procedure DrawImage(B: TBitmap; const R: TRect); 
    begin 
    Canvas.StretchDraw(R, B); 
    end; 

begin 
    Canvas.Brush.Style:= bsSolid; 
    Canvas.Pen.Style:= psClear; 
    Canvas.Brush.Color:= clWhite; 
    Canvas.FillRect(Canvas.ClipRect); 
    Bmp:= TBitmap.Create; 
    try 
    if Count > 0 then begin 
     case FSizing of 
     gsManual: begin 
      //Draw like regular grid with variable sizes - expand rows as needed 
      inherited; 

     end; 
     gsAuto: begin 
      //Calculate image width based on col count 

     end; 
     gsFit: begin 
      //Calculate col count based on image width 
      CC:= Trunc(ClientWidth/FColWidth); 
      RC:= Trunc(Count/CC); 
      ColCount:= CC; 
      RowCount:= RC; 
      for X := 0 to ColCount - 1 do 
      ColWidths[X]:= FColWidth; 
      for X := 0 to RowCount - 1 do 
      RowHeights[X]:= FRowHeight; 
      Canvas.Brush.Style:= bsSolid; 
      Canvas.Pen.Style:= psSolid; 
      Canvas.Brush.Color:= clWhite; 
      Canvas.Pen.Width:= 1; 
      C:= 0; //C = Count of items to show 
      for X := 0 to ColCount - 1 do begin 
      for Y := 0 to RowCount - 1 do begin 
       I:= Self.Items[C]; 
       if C = FItemIndex then begin 
       Canvas.Pen.Color:= clRed; 
       Canvas.Pen.Width:= 2; 
       end else begin 
       Canvas.Pen.Color:= clNavy; 
       Canvas.Pen.Width:= 1; 
       end; 
       R:= CellRect(X,Y); 
       Canvas.Rectangle(R); 
       InflateRect(R, -4, -4); 
       Canvas.StretchDraw(R, I.FBmp); 
       C:= C + 1; 
      end; 
      end; 
     end; 
     end; 
    end else begin 
     ColCount:= 1; 
     RowCount:= 1; 
    end; 
    finally 
    Bmp.Free; 
    end; 
end; 

procedure TImageGrid.SelectCell(Sender: TObject; ACol, ARow: Integer; 
    var CanSelect: Boolean); 
var 
    I: Integer; 
    C, R: Integer; 
begin 
    //Determine item index based on col/row 

    C:= ACol; 
    R:= ARow; 

    //I = Calculated index based on row/col (starts from 0) 
    //ACol = Column index user clicked (starts from 0) 
    //ARow = Row index user clicked (starts from 0) 
    //ColCount = Number of columns 

    I:= (R * ColCount) + C; //  <<----- FORMULA HERE 

    if I < Count - 1 then begin 
    FItemIndex:= I; 
    CanSelect:= True; 
    end else begin 
    FItemIndex:= -1; 
    CanSelect:= False; 
    end; 
    Invalidate; 
end; 

procedure TImageGrid.SetCacheDir(const Value: String); 
begin 
    if Value <> FCacheDir then begin 
    FCacheDir := Value; 
    Invalidate; 
    end; 
end; 

procedure TImageGrid.SetColWidth(const Value: Integer); 
begin 
    if Value <> FColWidth then begin 
    FColWidth := Value; 
    Invalidate; 
    end; 
end; 

procedure TImageGrid.SetItem(Index: Integer; const Value: TImageGridItem); 
begin 
    if (Index >= 0) and (Index < FItems.Count) then begin 
    FItems.Objects[Index]:= Value; 
    Invalidate; 
    end else begin 
    raise Exception.Create('List index out of bounds ('+IntToStr(Index)+')'); 
    end; 
end; 

procedure TImageGrid.SetItemIndex(const Value: Integer); 
begin 
    if Value <> FItemIndex then begin 
    FItemIndex := Value; 
    Invalidate; 
    end; 
end; 

procedure TImageGrid.SetRowHeight(const Value: Integer); 
begin 
    if Value <> FRowHeight then begin 
    FRowHeight := Value; 
    Invalidate; 
    end; 
end; 

procedure TImageGrid.SetSizing(const Value: TGridSizing); 
begin 
    if Value <> FSizing then begin 
    FSizing := Value; 
    Invalidate; 
    end; 
end; 

{ TImageGridItem } 

constructor TImageGridItem.Create(AOwner: TImageGrid); 
begin 
    FOwner:= AOwner; 
    FBmp:= TBitmap.Create; 
end; 

destructor TImageGridItem.Destroy; 
begin 
    FBmp.Free; 
    inherited; 
end; 

procedure TImageGridItem.Event; 
begin 
    FOwner.Invalidate; 
end; 

procedure TImageGridItem.LoadFile; 
    //Determine file type and load accordingly 
    function GetImage(const Filename: String; B: TBitmap): Bool; 
    var 
    E: String; 
    IJ: TJpegImage; 
    IP: TPngObject; 
    begin 
    Result:= False; 
    if FileExists(Filename) then begin 
     E:= UpperCase(ExtractFileExt(Filename)); 
     if E = '.BMP' then begin 
     B.LoadFromFile(Filename); 
     Result:= True; 
     end else 
     if (E = '.JPG') or (E = '.JPEG') then begin 
     IJ:= TJpegImage.Create; 
     try 
      IJ.LoadFromFile(Filename); 
      B.Assign(IJ); 
      Result:= True; 
     finally 
      IJ.Free; 
     end; 
     end else 
     if E = '.PNG' then begin 
     IP:= TPngObject.Create; 
     try 
      IP.LoadFromFile(Filename); 
      B.Assign(IP); 
      Result:= True; 
     finally 
      IP.Free; 
     end; 
     end else begin 
     raise Exception.Create('Invalid file extension ('+E+')'); 
     end; 
    end; 
    end; 

begin 
    GetImage(FFilename, FBmp); 
end; 

procedure TImageGridItem.SetFilename(const Value: TFilename); 
begin 
    if Value <> FFilename then begin 
    FFilename := Value; 
    LoadFile; 
    Event; 
    end; 
end; 

end. 

でマークされ、私はそれが固定してしまいました。最初は数式が間違っていると思っていましたが、コードのスコープを増やした後、別の場所では行と列が不適切にループしていました。以下は...それがどのように動作するかを

for Y := 0 to RowCount - 1 do begin 
    for X := 0 to ColCount - 1 do begin 

しかし、私が前にいたていたが...

for X := 0 to ColCount - 1 do begin 
    for Y := 0 to RowCount - 1 do begin 

Answer 1

次のトリックをあなたの例については

(R * ColCount) + C 

を行う必要があり、このうになります

(2 * 3) + 2 = 8 

と...が3列あり、かつC2/R1をユーザーがクリックすると、それがどのように `（R * COLCOUNT）+ C`について5

(1 * 3) + 2 = 5