mainview.pas

Delphi利用MVC开发的典型例子

unit MainView;

// This code was generated by the EasyMVC OTA Wizard
// www.eazisoft.com

interface
uses
  Windows, Messages, SysUtils, Classes, Graphics,
  Controls, StdCtrls, ComCtrls, ExtCtrls, Forms, patterns, Menus,
  IndexTreeView;

type
  TViewMain = class(TFORM, IObserver)
    MainMenu1: TMainMenu;
    File1: TMenuItem;
    mnuExit: TMenuItem;
    Help1: TMenuItem;
    mnuAbout: TMenuItem;
    mnuHelp: TMenuItem;
    PageControl1: TPageControl;
    TabSheet1: TTabSheet;
    StatusBar1: TStatusBar;
    Splitter1: TSplitter;
    pnlIndex: TPanel;
    Label1: TLabel;
    procedure mnuExitClick(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
  private
    FIndexFrame: TFrame;
    { Private declarations }
    procedure UpdateView(o: TObject); //from IObserver
    procedure setIndexFrame(AFrame: TFrame);
    procedure setInfo(s: string);
  public

    { Public declarations }
    procedure setNotifyEventHandler(ANotifyEvent: TNotifyEvent);

    procedure UnLoadFrames;
  end;

implementation
uses commandlist;
{$R *.dfm}

procedure TViewMain.UnLoadFrames;
begin
  if assigned(self.fIndexFrame) then
  begin
    findexFrame.parent := nil;
    findexFrame := nil;
  end;
end;

procedure TViewMain.setInfo(s: string);
begin
  label1.Caption := s;
end;

procedure TViewMain.UpdateView(o: TObject);
var
  cmd: TCommand;
begin
  {write your code here}
  if o is TCommand then
  begin
    cmd:= TCommand(o);
    if cmd.equals(CMD_SHOW_INDEXTREE) then
    begin
      setIndexFrame(TFrame(cmd.getParamObject));
    end
    else if cmd.equals(CMD_TREEINDEX_SELECT) then
    begin
      self.setInfo(TCommand(cmd.getParamObject).getCommandTxt);
    end;
  end;
  freeAndNil(o);
end;

procedure TViewMain.setIndexFrame(AFrame: TFrame);
begin
  if assigned(AFrame) and (AFrame <> FIndexFrame) then
  begin
    UnLoadFrames;
    self.findexFrame := AFrame;
    findexFrame.Parent := pnlIndex;
    findexFrame.Align := alClient;
  end;
end;

procedure TViewMain.mnuExitClick(Sender: TObject);
begin
  close;
  //it's no neccessary to ask the Controller determine everything
end;

procedure TViewMain.setNotifyEventHandler(ANotifyEvent: TNotifyEvent);
begin
  if assigned(ANotifyEvent) then
  begin
    mnuHelp.OnClick := ANotifyEvent;
    mnuAbout.OnClick := ANotifyEvent;
  end;
end;

procedure TViewMain.FormDestroy(Sender: TObject);
begin
  //must unload the indexframe,otherwise it will be released by MainView
  self.UnLoadFrames;
end;

end.