Listview控件 改良版，带箭头自动排序[转]

{
似乎很多人都需要这个。
Delphi自带的listview无法在排序时自动加上箭头。
如果设置Column[I].ImageIndex = a，箭头会出现在文字左边，
需要修改ComCtrls.pas才能使图片出现在右边。
并且TListItem的Caption项会自动加上图标，
没有图标则留出一个空白，非常难看。
这个修改过的控件解决了这些问题。
这个控件需要从资源文件中装载两个箭头图片，你需要自己制作。
或者下载SJListview，里面有SJListview.res资源文件。
}

{*******************************************************} {                                                       } {  ComponentName : SJListView                           } {  Version       : 2.2a                                 } {  Author        : SJ(小笨苯)                           } {  E_Mail        : taibenle@163.com                     } {  Last Modified : 2002-5-15                            } {  History       :                                      } {  修改          : 2004-12-25 afan                      } {                                                       } {*******************************************************} unit SJListView; interface uses   Windows, Messages, SysUtils, Classes, ComCtrls, Commctrl; type   TListView2 = class(TListView)   private     { Private declarations }     ArrowUp : HBitMap;     ArrowDown : HBitMap;     CurColumn: integer;     vHandle: HWND;     procedure SetHeaderBitmap(Col: integer);//画Header   protected     { Protected declarations }     //procedure WndProc(var Msg : TMessage); override;   public     { Public declarations }     constructor Create(AOwner: TComponent); override;     procedure CreateWnd; override;     destructor Destroy; override;   published     { Published declarations }   end; type   TMainListview = class(TListview2)   protected     procedure WndProc(var Msg: TMessage); override;   end; type   TMyListview = class(TListview2)   protected     procedure WndProc(var Msg: TMessage); override;   end; procedure Register; implementation {R SJListView.res} { 通用排序函数 } Function CustomSortProc( Item1, Item2 : TListItem; lParam : LongInt  : Integer; stdcall; begin    Result:=0;    if (Item1=nil)or(Item2=nil)then      exit;    if lParam = 0 then       result := CompareText(Item1.Caption,Item2.Caption    else if lparam > 0 then       result := CompareText(Item1.SubItems[Lparam-1],Item2.SubItems[Lparam-1]);    Result:= Result * Item1.ListView.Column[lParam].Tag ; end; function CustomSortProcMain( Item1, Item2 : TListItem; lParam : LongInt  : Integer; stdcall; var   ip1,ip2:cardinal;   s1,s2:String; begin    Result:= Result * Item1.ListView.Column[lParam].Tag ; end; constructor TListview2.Create(AOwner: TComponent); begin   inherited Create(AOwner);   ArrowUp := LoadImage(hInstance, 'ArrowUp', IMAGE_BITMAP, 0, 0, LR_LOADMAP3DCOLORS);   ArrowDown := LoadImage(hInstance, 'ArrowDown', IMAGE_BITMAP, 0, 0, LR_LOADMAP3DCOLORS);   //SetHeaderBitmap; end; procedure TListview2.CreateWnd; begin   inherited CreateWnd;   if HandleAllocated then HandleNeeded;   vHandle := ListView_GetHeader(Handle); end; destructor TListview2.Destroy; begin   DeleteObject(ArrowUp);   DeleteObject(ArrowDown);   inherited Destroy; end; procedure TListview2.SetHeaderBitmap(Col: integer); var   HdItem : THdItem; begin   FillChar(HdItem, SizeOf(HdItem), #0);   HdItem.Mask := HDI_FORMAT;   Header_GetItem(vHandle, Col, HdItem);   HdItem.Mask := HDI_BITMAP or HDI_FORMAT;   if Column[Col].Tag = -1 then begin { 反向 }     HdItem.fmt := HdItem.fmt or HDF_BITMAP or HDF_BITMAP_ON_RIGHT;     HdItem.hbm := LoadImage(hInstance, 'ArrowDown', IMAGE_BITMAP, 0, 0, LR_LOADMAP3DCOLORS);   end   else if Column[Col].Tag = 1 then begin { 正向 }     HdItem.fmt := HdItem.fmt or HDF_BITMAP or HDF_BITMAP_ON_RIGHT;     HdItem.hbm := LoadImage(hInstance, 'ArrowUp', IMAGE_BITMAP, 0, 0, LR_LOADMAP3DCOLORS);   end   else if Column[Col].Tag = 0 then begin{ 消除箭头 }     HdItem.fmt := HdItem.fmt and not (HDF_BITMAP or HDF_BITMAP_ON_RIGHT);     HdItem.hbm := 0;   end;   Header_SetItem(vHandle, Col, HdItem); end; (* procedure TListview2.WndProc(var Msg : TMessage); var   pHD : PHDNotify;   i: integer; begin   inherited WndProc(Msg);   if Msg.Msg = WM_NOTIFY then //如果截获的消息是WM_NOTIFY   begin     pHD := PHDNotify(Msg.LParam);     HwndFrom:= pHD.Hdr.hwndFrom ;     if (hwndFrom = vHandle) and (vHandle <> 0) then begin       wmCode:= 0;       Case pHD.HDr.code of         { 如果是点击Header }         HDN_ITEMCLICK,HDN_ITEMCLICKW:           begin             CurColumn := Columns.Items[pHD.item].Index;             wmCode:= pHD.Hdr.code ;             { 做标记，正向或反向排序 }               for i:= 0 to Columns.Count - 1 do begin                 if I = CurColumn then begin                   if Column[I].Tag = 0 then                     Column[I].Tag := 1                   else                     Column[I].Tag := -1 * Column[I].Tag ;                   SetHeaderBitmap(I);                 end                 else begin                   if Column[I].Tag <> 0 then begin                     Column[I].Tag := 0;                     SetHeaderBitmap(I);                   end;                 end;               end; {of FOR}             { 排序 }             //CustomSort(@CustomSortProc, CurColumn);           end;         { 拖动改变宽度时，ColumnItem <> 原来排序的列 }         HDN_ENDTRACK,HDN_ENDTRACKW:           Begin             CurColumn:= Columns.Items[pHD.item].Index;             if Columns[CurColumn].Tag <> 0 then               SetHeaderBitmap(CurColumn);           end;       end;     end;   end; end; *) Procedure TMyListview.WndProc(var Msg: TMessage); var   pHD : PHDNotify;   i: integer; begin   inherited WndProc(Msg);   if Msg.Msg = WM_NOTIFY then //如果截获的消息是WM_NOTIFY   begin     pHD := PHDNotify(Msg.LParam);     if (pHD.Hdr.hwndFrom = vHandle) and (vHandle <> 0) then begin       Case pHD.HDr.code of         { 如果是点击Header }         HDN_ITEMCLICK,HDN_ITEMCLICKW:           begin             CurColumn := Columns.Items[pHD.item].Index;             { 做标记，正向或反向排序 }               for i:= 0 to Columns.Count - 1 do begin                 if I = CurColumn then begin                   if Column[I].Tag = 0 then                     Column[I].Tag := 1                   else                     Column[I].Tag := -1 * Column[I].Tag ;                   SetHeaderBitmap(I);                 end                 else begin                   if Column[I].Tag <> 0 then begin                     Column[I].Tag := 0;                     SetHeaderBitmap(I);                   end;                 end;               end; {of FOR}             { 排序 }             CustomSort(@CustomSortProc, CurColumn);           end;         { 拖动改变宽度时，ColumnItem <> 原来排序的列 }         HDN_ENDTRACK,HDN_ENDTRACKW:           Begin             CurColumn:= Columns.Items[pHD.item].Index;             if Columns[CurColumn].Tag <> 0 then               SetHeaderBitmap(CurColumn);           end;       end;     end;   end; end; procedure TMainListview.WndProc(var Msg: TMessage); var   pHD : PHDNotify;   i: integer; begin   inherited WndProc(Msg);   if Msg.Msg = WM_NOTIFY then //如果截获的消息是WM_NOTIFY   begin     pHD := PHDNotify(Msg.LParam);     if (pHD.Hdr.hwndFrom = vHandle) and (vHandle <> 0) then begin       Case pHD.HDr.code of         { 如果是点击Header }         HDN_ITEMCLICK,HDN_ITEMCLICKW:           begin             CurColumn := Columns.Items[pHD.item].Index;             { 做标记，正向或反向排序 }               for i:= 0 to Columns.Count - 1 do begin                 if I = CurColumn then begin                   if Column[I].Tag = 0 then                     Column[I].Tag := 1                   else                     Column[I].Tag := -1 * Column[I].Tag ;                   SetHeaderBitmap(I);                 end                 else begin                   if Column[I].Tag <> 0 then begin                     Column[I].Tag := 0;                     SetHeaderBitmap(I);                   end;                 end;               end; {of FOR}             { 排序 }             CustomSort(@CustomSortProcMain, CurColumn);           end;         { 拖动改变宽度时，ColumnItem <> 原来排序的列 }         HDN_ENDTRACK,HDN_ENDTRACKW:           Begin             CurColumn:= Columns.Items[pHD.item].Index;             if Columns[CurColumn].Tag <> 0 then               SetHeaderBitmap(CurColumn);           end;       end;     end;   end; end; procedure Register; begin   RegisterComponents('Win32', [TMainListView, TMyListview]); end; end.

附：如何在TListView中显示数据库内容

procedure TForm1.FormCreate(Sender: TObject); var     i:Integer;     TempColumn:TListColumn;     TempItem:TListItem; begin     ListView1.ViewStyle:=vsReport;     for i:=0 to Query1.FieldCount-1 do     begin         TempColumn:=self.ListView1.Columns.Add;         TempColumn.Caption:=Query1.Fields[i].FieldName;     end;     Query1.First;     while not Query1.Eof do     begin         TempItem:=self.ListView1.Items.Add;         TempItem.Caption:=Query1.Fields[0].AsString;         for i:=1 to Query1.FieldCount-1 do         begin             TempItem.SubItems.Add(Query1.Fields[i].AsString);         end;         Query1.Next;     end; end;