学习 TTreeView [12] - FullExpand、FullCollapse、GetNodeAt

本例效果图:

---

unit Unit1;



interface



uses

  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

  Dialogs, StdCtrls, ComCtrls;



type

  TForm1 = class(TForm)

    TreeView1: TTreeView;

    Button1: TButton;

    Button2: TButton;

    procedure FormCreate(Sender: TObject);

    procedure Button1Click(Sender: TObject);

    procedure Button2Click(Sender: TObject);

    procedure TreeView1MouseMove(Sender: TObject; Shift: TShiftState; X,

      Y: Integer);

  end;



var

  Form1: TForm1;



implementation



{$R *.dfm}



{我随意地使用了不同的方法去动态添加数据}

procedure TForm1.FormCreate(Sender: TObject);

var

  stream: TMemoryStream;

begin

  TreeView1.Align := alLeft;

  stream := TMemoryStream.Create;

  with TStringList.Create do

  begin

    Add('一连长');

    Add(#9+'一排长');

    Add(#9+#9+'一班长');

    Add(#9+#9+#9+'战士1');

    Add(#9+#9+#9+'战士2');

    Add(#9+#9+#9+'战士3');

    Add(#9+#9+#9+'战士4');

    Add(#9+#9+'二班长');

    Add(#9+#9+'三班长');

    Add(#9+'二排长');

    Add(#9+'三排长');

    Add('二连长');

    Add('三连长');

    SaveToStream(stream);

    Free;

  end;

  stream.Position := 0;

  TreeView1.LoadFromStream(stream);

  stream.Free;

end;



procedure TForm1.Button1Click(Sender: TObject);

begin

  TreeView1.FullExpand;

  (Sender as TButton).Caption := '全部展开';

end;



procedure TForm1.Button2Click(Sender: TObject);

begin

  TreeView1.FullCollapse;

  (Sender as TButton).Caption := '全部关闭';

end;



procedure TForm1.TreeView1MouseMove(Sender: TObject; Shift: TShiftState; X,

  Y: Integer);

var

  node: TTreeNode;

begin

  if Boolean(TreeView1.GetNodeAt(X,Y)) then

  begin

    node := TreeView1.GetNodeAt(X,Y);

    Text := node.Text;

  end;

end;



end.