cxGrid显示行号的两种方式和两种代码

第一种方式：直接双击events中的对应OnCustomDrawIndicatorCell事件，使用此代码

//==============================================================================

// 显示cxGrid的行号

//==============================================================================

procedure TFormMainOperation.cxgrddbbandtv1CustomDrawIndicatorCell(

  Sender: TcxGridTableView; ACanvas: TcxCanvas;

  AViewInfo: TcxCustomGridIndicatorItemViewInfo; var ADone: Boolean);

var

  AIndicatorViewInfo: TcxGridIndicatorRowItemViewInfo;

  ATextRect: TRect;

 // AStyle: TcxStyle;

  aCV: TcxCanvas;

begin

  if not (AViewInfo is TcxGridIndicatorRowItemViewInfo) then

    Exit;

  aCV := ACanvas;

  ATextRect := AViewInfo.ContentBounds;

  AIndicatorViewInfo := AViewInfo as TcxGridIndicatorRowItemViewInfo;

  InflateRect(ATextRect, -2, -1);

  if AIndicatorViewInfo.GridRecord.Selected then //这个if段是为了在行号处把把选中的行号跟别的区分开，可不用

    begin

      aCV.Font.Style := Canvas.Font.Style + [fsBold];

      aCV.Font.Name := '黑体';

      aCV.Font.Size := 12;

      aCV.Font.Color := clRed;

    end

  else

    begin

      aCV.Font.Style := Canvas.Font.Style - [fsBold];

      acv.Font.Color := Canvas.Font.Color;

    end;

  Sender.LookAndFeelPainter.DrawHeader(ACanvas, AViewInfo.ContentBounds,

    ATextRect, [], cxBordersAll, cxbsNormal, taCenter, vaCenter,

    False, False, IntToStr(AIndicatorViewInfo.GridRecord.Index + 1),

//    AStyle.Font, AStyle.TextColor, AStyle.Color);

    acv.Font, acv.font.Color, acv.Brush.color);

  ADone := True;

end;

第二种方式：使用封装类，建立储存过程，Form初始化OnCreate事件中调用

1、建立封装类和调用函数

unit UnitDevExpressVCLCustom;

interface

uses

  cxGridTableView, cxGridDBBandedTableView, Winapi.Windows, System.SysUtils, cxClasses,

  System.Classes, Vcl.Graphics, cxGraphics, cxLookAndFeels, cxLookAndFeelPainters;

type

  TMyCxGrid = class(TObject)

    class procedure DrawIndicatorCell(Sender: TcxGridTableView; ACanvas: TcxCanvas;

      AViewInfo: TcxCustomGridIndicatorItemViewInfo; var ADone: Boolean);

  end;

  procedure ShowLineNo(cxGridDBBandedTableView: TcxGridDBBandedTableView);

implementation

{-------------------------------------------------------------------------------

  作者:      曾聪

  日期:      2013.10.07

  过程名:    TMyCxGrid.DrawIndicatorCell

  功能:      显示cxGrid的行号

  参数:      Sender: TcxGridTableView; ACanvas: TcxCanvas; AViewInfo: TcxCustomGridIndicatorItemViewInfo; var ADone: Boolean

  返回值:    无

  说明:

-------------------------------------------------------------------------------}

class procedure TMyCxGrid.DrawIndicatorCell(Sender: TcxGridTableView; ACanvas: TcxCanvas;

  AViewInfo: TcxCustomGridIndicatorItemViewInfo; var ADone: Boolean);

var

  FValue: string;

  FBounds: TRect;

  //method 2

  AIndicatorViewInfo: TcxGridIndicatorRowItemViewInfo;

  ATextRect: TRect;

  AFont: TFont;

  AFontTextColor, AColor: TColor;

begin

  AFont := ACanvas.Font;

  AColor := clBtnFace;

  AFontTextColor := clWindowText;

  if (AViewInfo is TcxGridIndicatorHeaderItemViewInfo) then //设置显示行号那一列的标题名称为“序号”

    begin

      ATextRect := AViewInfo.Bounds;

      InflateRect(ATextRect, -1, -1);

      Sender.LookAndFeelPainter.DrawHeader(ACanvas, AViewInfo.Bounds,

        ATextRect, [], cxBordersAll, cxbsNormal, taCenter, TcxAlignmentVert.vaCenter,

        False, False, '序号', AFont, AFontTextColor, AColor);

      ADone := True;

    end;

  if not (AViewInfo is TcxGridIndicatorRowItemViewInfo) then

    Exit;

  ATextRect := AViewInfo.ContentBounds;

  AIndicatorViewInfo := AViewInfo as TcxGridIndicatorRowItemViewInfo;

  InflateRect(ATextRect, -1, -1);

  if AIndicatorViewInfo.GridRecord.Selected then //这个if段是为了在行号处把把选中的行号跟别的区分开，可不用

    begin

      AFont.Style := ACanvas.Font.Style + [fsBold];

      AFont.Name := '黑体';

      AFont.Size := 12;

      AFont.Color := clRed;

    end

  else

    begin

      AFont.Style := ACanvas.Font.Style - [fsBold];

    end;

  Sender.LookAndFeelPainter.DrawHeader(ACanvas, AViewInfo.ContentBounds,

    ATextRect, [], [bBottom, bLeft, bRight], cxbsNormal, taCenter, TcxAlignmentVert.vaCenter,

    False, False, IntToStr(AIndicatorViewInfo.GridRecord.Index + 1),

    AFont, AFontTextColor, AColor);

  ADone := True;

end;

{-------------------------------------------------------------------------------

  作者:      曾聪

  日期:      2013.10.07

  过程名:    ShowLineNo

  功能:      设置cxGrid显示导航列、导航列宽、调用显示行号函数

  参数:      cxGridDBBandedTableView: TcxGridDBBandedTableView

  返回值:    无

  说明:

-------------------------------------------------------------------------------}

procedure ShowLineNo(cxGridDBBandedTableView: TcxGridDBBandedTableView);

begin

  cxGridDBBandedTableView.OptionsView.Indicator := True;

  cxGridDBBandedTableView.OptionsView.IndicatorWidth := 30;

  cxGridDBBandedTableView.OnCustomDrawIndicatorCell := TMyCxGrid.DrawIndicatorCell;

end;

end.

2、在Form的OnCreate事件中调用：

procedure TFormMainOperation.FormCreate(Sender: TObject);

begin

  ShowLineNo(cxgrddbbandtv1);

end;

以上代码如果需要在右侧仍然显示指针效果：

1、在最后一行end之前增加一行代码：

Sender.LookAndFeelPainter.DrawIndicatorImage(ACanvas, ATextRect, AIndicatorViewInfo.IndicatorKind);

2、在DrawIndicatorImage 从这里跟进去(Ctrl+左键单击) 
在 cxLookAndFeelPainters 单元中作如下修改: 
class procedure TcxCustomLookAndFeelPainter.DrawIndicatorImage(ACanvas: TcxCanvas; 
   const R: TRect; AKind: TcxIndicatorKind); 
var 
   X, Y: Integer; 
begin 
   if AKind = ikNone then Exit; 
   with cxIndicatorImages, R do 
   begin 
     X := (Left + Right - Width);              
//靠右,在各函数只修改这一个地方 
     Y := (Top + Bottom - Height) div 2;       //居中 
   end; 
   cxIndicatorImages.Draw(ACanvas.Canvas, X, Y, Ord(AKind) - 1); 
end; 
注意,我已注明靠右的那一行, 就是去掉 DIV 2 了, 此为1226版本的修改，13.1.2修改类似也是去掉DIV
2，但是左右宽的代码使用的是变量R.Left等
3、还要改一个地方: 
SKIN控件目录下的dxSkinLookAndFeelPainter单元,找到 
TdxSkinLookAndFeelPainter.DrawIndicatorImage 函数 
的 
OffsetRect(ARect, (Left + Right - cx div 2) , (Top + Bottom - cy) div 2); 
这一行,将 (Left + Right - cx div 2) 改为(Left + Right - cx) 也是去掉 div 2 就是靠右; 
修改后: OffsetRect(ARect, (Left + Right - cx) , (Top + Bottom - cy) div 2); 
使用 
procedure TForm1.cxGrid1DBTableView1CustomDrawIndicatorCell( 
   Sender: TcxGridTableView; ACanvas: TcxCanvas; 
   AViewInfo: TcxCustomGridIndicatorItemViewInfo; var ADone: Boolean); 
begin 
     SetRowNumber(Sender,AviewInfo,ACanvas,ADone); 
end; 
序号列的列宽最好改为40左右，因为数据记录过多会出现重叠现象（数字和指针图标在一起了）!