Delphi中dxTreelist控件的使用.docx

Delphi中dxTreelist控件的使用 最近公司项目中用到dxTreelist控件，以前没怎么用过这个控件，该控件比TreeView功能更强大，要完全掌握还真不容易，下面是我个人做的一个Demo，对该控件进行增删改遍历操作，以便自己以后忘了使用方法随时可以查吧。1.首先新建一个数据库。 打开SQL Server2005，新建数据库TreeTest，新建表DeviceTab，表的字段设计如下: 2.新建Delphi应用程序选择File-New-Application新建应用程序，File-New-Data Module，新建一个数据库模块，添加TADOConnection和TImageList控件,设置ADOConnection的LoginPrompt为false，给ImageList控件添加7个图片,该数据模块的Create事件代码如下: procedure Tdm.DataModuleCreate(Sender: TObject); begin if not con1.Connected then begin /设置连接字符串 con1.ConnectionString:=Provider=SQLOLEDB.1;Password=123456;Persist Security Info=True;User ID=sa;Initial Catalog=TreeList;Data Source=ZHSQLEXPRESS; con1.Open; /打开数据库连接 end; end; 在窗体上放置dxTreeList控件和四个Button控件以及一个Timer控件设置Timer控件的Interval属性为100,各按钮相关事件及源码如下：unit Main;interfaceuses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, dxExEdtr, dxCntner, dxTL, dxTLClms,ADODB, Menus, cxLookAndFeelPainters, StdCtrls, cxButtons, ExtCtrls;type TfrmTree = class(TForm) dxTreeList1: TdxTreeList; btnAddNode: TcxButton; btnDelNode: TcxButton; btnUpdate: TcxButton; btnbl: TcxButton; tmr1: TTimer; procedure btnblClick(Sender: TObject); procedure btnAddNodeClick(Sender: TObject); procedure btnDelNodeClick(Sender: TObject); procedure btnUpdateClick(Sender: TObject); procedure tmr1Timer(Sender: TObject); procedure FormDestroy(Sender: TObject); private Private declarations public Public declarations procedure CreateColumn(tree:TdxTreeList;list:TStrings); procedure CreateImageColumn(tree:TdxTreeList;Image:TImageList); procedure FillTree(node:TdxTreeListNode;pid:Integer;con:TADOConnection); function GetMaxId(con:TADOConnection):Integer; procedure DelTree(pid:Integer;con:TADOConnection); procedure UpdateTree(newname:string;id:Integer;con:TADOConnection); function GetCount(tree:TdxTreeList):Integer; end;var frmTree: TfrmTree;implementation$R *.dfmuses unitDM;var list:TStrings;procedure TfrmTree.CreateColumn(tree:TdxTreeList;list:TStrings); /动态创建dxTreeList的列var i:Integer; col:TdxTreeListColumn;begin for i:=0 to list.Count-1 do begin col:=tree.CreateColumn(TdxTreeListMaskColumn); col.Caption:=listi; /显示标题 col.ColIndex:=i; /列索引 col.Name:=listi; /列标识 col.Width:=90+10*i; /列宽 end;end;procedure TfrmTree.CreateImageColumn(tree:TdxTreeList;Image:TImageList);/创建带图片的列var col:TdxTreeListColumn; i:Integer;begin col:=tree.CreateColumn(TdxTreeListImageColumn); col.Width:=50; col.Name:=img; TdxTreeListImageColumn(col).Images:=Image; for i:=0 to image.Count-1 do/关联图片 begin TdxTreeListImageColumn(col).ImageIndexes.Add(IntToStr(i); TdxTreeListImageColumn(col).Values.Add(IntToStr(i); end;end;procedure TfrmTree.FillTree(node: TdxTreeListNode; pid: Integer;con:TADOConnection);/构造树var tmpnode:TdxTreeListNode; ADOQuery:TADOQuery;begin ADOQuery:=TADOQuery.Create(nil); try ADOQuery.Connection:=con; ADOQuery.Close; ADOQuery.SQL.Clear; ADOQuery.SQL.Text:=select * from DeviceTab where pid=+Inttostr(pid); ADOQuery.Open; with ADOQuery do begin First; while not Eof do begin if node=nil then tmpnode:=dxTreeList1.Add /添加根节点 else tmpnode:=node.AddChild; /添加子节点 pid:=FieldByName(id).AsInteger; tmpnode.Strings0:=IntToStr(pid); tmpnode.Strings1:=FieldByName(pid).AsString; tmpnode.Strings2:=FieldByName(aName).AsString; tmpnode.Strings3:=IntToStr(tmpnode.Level); tmpnode.ImageIndex:=tmpnode.Level; tmpnode.SelectedIndex:=tmpnode.Level; FillTree(tmpnode,pid,con); /递归添加子节点 Next; end; end; finally ADOQuery.Free; end;end;procedure TfrmTree.btnblClick(Sender: TObject); /遍历子节点var node,tmpnode:TdxTreeListNode; i:Integer; str:string;begin if dxTreeList1.Count=0 then Exit; node:=dxTreeList1.FocusedNode; /获取焦点的节点 for i:=0 to dxTreeList1.ColumnCount-1 do str:=str+node.Stringsi+; ShowMessage(str); tmpnode:=node.GetFirstChild; /获取第一个子节点 while tmpnodenil do begin str:=; for i:=0 to dxTreeList1.ColumnCount-1 do str:=str+tmpnode.Stringsi+; ShowMessage(str); /if tmpnode=node.GetLastChild then break; if (tmpnode=node.GetLastChild) and (not tmpNode.HasChildren) then break; /判断是否为最后一个子节点是终止循环 tmpnode:=tmpnode.GetNext; /获取下一个节点 end;end;procedure TfrmTree.btnAddNodeClick(Sender: TObject); /添加节点var node:TdxTreeListNode; i:Integer; idindex,pidIndex,anameindex,imgIndex:Integer; id,pid:integer; aname:string; qry:TADOQuery; IsExist:Boolean;begin aname:=; pid:=0; for i:=0 to dxTreeList1.ColumnCount-1 do begin if dxTreeList1.Columnsi.Name=aName then begin anameindex:=i; end else if dxTreeList1.Columnsi.Name=id then begin idindex:=i; end else if dxTreeList1.Columnsi.Name=pid then begin pidIndex:=i; end else if dxTreeList1.Columnsi.Name=img then begin imgIndex:=i; end; end; if InputQuery(添加节点,请输入节点名称,aname) then begin if dxTreeList1.Count=0 then begin node:=dxTreeList1.Add; /添加根节点 end else begin node:=dxTreeList1.FocusedNode; if node.Level=6 then begin ShowMessage(已经添加到节点极限); exit; end; pid:=StrToIntDef(node.Stringsidindex,0); node:=node.AddChild; /添加子节点 end; id:=GetMaxId(dm.con1)+1; node.Stringsidindex:=IntToStr(id); node.StringspidIndex:=IntToStr(pid); node.Stringsanameindex:=aname; node.StringsimgIndex:=IntToStr(node.Level); node.ImageIndex:=node.Level; node.SelectedIndex:=node.Level; try qry:=TADOQuery.Create(nil); qry.Connection:=dm.con1; qry.Close; qry.SQL.Clear; qry.SQL.Text:=insert into DeviceTab values(+inttostr(id)+,+Inttostr(pid)+,+QuotedStr(aname)+); qry.ExecSQL; finally qry.Free; end; end;end;function TfrmTree.GetMaxId(con: TADOConnection): Integer; /获取最大ID值var qry:TADOQuery;begin try qry:=TADOQuery.Create(nil); qry.Connection:=con; with qry do begin close; sql.Clear; SQL.Add(select Max(id) as mid from DeviceTab); Open; First; Result:=qry.FieldByName(mid).AsInteger; end; finally qry.Free; end; end;procedure TfrmTree.btnDelNodeClick(Sender: TObject); /删除节点var node:TdxTreeListNode; i,aid:integer;begin if dxTreeList1.Count=0 then begin ShowMessage(没有要删除的节点); Exit; end else begin node:=dxTreeList1.FocusedNode; if MessageBox(Self.Handle,PChar(确定要删除该节点及其所有的子节点吗?),PChar(删除提示),MB_OKCANCEL)IdOK then Exit; if node.HasChildren then node.DeleteChildren; /删除子节点 for i:=0 to dxTreeList1.ColumnCount-1 do begin if dxTreeList1.Columnsi.Name=id then begin aid:=i; Break; end end; DelTree(StrToIntDef(node.Stringsaid,0),dm.con1); node.Free; end;end;procedure TfrmTree.DelTree(pid: Integer;con: TADOConnection); /删除数据库节点记录var tmpnode:TdxTreeListNode; ADOQuery:TADOQuery;begin ADOQuery:=TADOQuery.Create(nil); try ADOQuery.Connection:=con; with ADOQuery do begin Close; SQL.Clear; SQL.Text:=delete from DeviceTab where id=+Inttostr(pid); /删除当前节点记录 ExecSQL; end; ADOQuery.Close; ADOQuery.SQL.Clear; ADOQuery.SQL.Text:=select * from DeviceTab where pid=+Inttostr(pid); /查找子节点记录 ADOQuery.Open; with ADOQuery do begin First; while not Eof do begin DelTree(FieldByName(id).AsInteger,con); /递归删除下级记录 Next; end; end; finally ADOQuery.Free; end;end;procedure TfrmTree.btnUpdateClick(Sender: TObject); 修改var node:TdxTreeListNode; aname:string; i,j,k,id:Integer; IsExist:Boolean;begin IsExist:=False; if dxTreeList1.Count=0 then begin ShowMessage(没有要修改的节点); exit; end else begin dxTreeList1.BeginUpdate; node:=dxTreeList1.FocusedNode; for i:=0 to dxTreeList1.ColumnCount-1 do begin if dxTreeList1.Columnsi.Name=aName then begin j:=i; aname:=node.Stringsi; Break; end else if dxTreeList1.Columnsi.Name=id then begin k:=i; id:=StrToIntDef(node.Stringsi,0); end; end; if InputQuery(修改节点,请输入修改后的节点名,aname) then begin node.Stringsj:=aname; UpdateTree(aname,id,dm.con1);/更新数据库记录 end; end; dxTreeList1.EndUpdate;end;procedure TfrmTree.UpdateTree(newname: string; id: Integer; con: TADOConnection);var qry:TADOQuery;begin qry :=TADOQuery.Create(nil); try with qry do begin Connection:=con; Close; SQL.Clear; SQL.Text:=update DeviceTab set aname=+Quotedstr(newname)+ where id=+Inttostr(id); ExecSQL; end; finally qry.Fr