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;

procedure TMainListview.WndProc(var Msg: TMessage);
var
  pHD : PHDNotify;
  i: integer;
begin
  inherited WndProc(Msg);

{ 排序 }
            CustomSort(@CustomSortProcMain, CurColumn);
          end;

procedure Register;
begin
  RegisterComponents('Win32', [TMainListView, TMyListview]);
end;

end.

附：如何在TListView中显示数据库内容

posted @ 2009-05-02 10:02 小宇飞刀阅读(353) 评论(0) 编辑收藏举报

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Listview控件 -- 改良版，带箭头自动排序[转]

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