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;
    PageControl2: TPageControl;
    TabSheet2: TTabSheet;
    pnlChildren: TPanel;
    Panel1: TPanel;
    Splitter2: TSplitter;
    pnlMother: TPanel;
    Splitter3: TSplitter;
    pnlFather: TPanel;
    procedure mnuExitClick(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
  private
    FIndexFrame,
      FFatherFrame,
      FMotherFrame,
      FBabyFrame: TFrame;
    { Private declarations }
    procedure UpdateView(o: TObject); //from IObserver
//    procedure setIndexFrame(AFrame: TFrame);
    procedure setFrame(AFrame: TFrame; AParent: TPanel);
    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;

  if assigned(FFatherFrame) then
  begin
    FFatherFrame.parent := nil;
    FFatherFrame := nil;
  end;

  if assigned(FMotherFrame) then
  begin
    FMotherFrame.parent := nil;
    FMotherFrame := nil;
  end;

  if assigned(FBabyFrame) then
  begin
    FBabyFrame.parent := nil;
    FBabyFrame := 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) and (self.FIndexFrame <> TFrame(cmd.getParamObject)) then
    begin
      self.FIndexFrame := TFrame(cmd.getParamObject);
      setFrame(TFrame(cmd.getParamObject), pnlIndex);
    end
    else if cmd.equals(CMD_SHOW_FATHERVIEW) and (self.FFatherFrame <> TFrame(cmd.getParamObject)) then
    begin
      self.FFatherFrame := TFrame(cmd.getParamObject);
      setFrame(TFrame(cmd.getParamObject), pnlFather);
    end
    else if cmd.equals(CMD_SHOW_MOTHERVIEW) and (self.FMotherFrame <> TFrame(cmd.getParamObject)) then
    begin
      self.FMotherFrame := TFrame(cmd.getParamObject);
      setFrame(TFrame(cmd.getParamObject), pnlMother);
    end
    else if cmd.equals(CMD_SHOW_CHILDRENVIEW) and (self.FBabyFrame <> TFrame(cmd.getParamObject)) then
    begin
      self.FBabyFrame := TFrame(cmd.getParamObject);
      setFrame(TFrame(cmd.getParamObject), pnlChildren);
    end

    else if cmd.equals(CMD_NODE_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.setFrame(AFrame: TFrame; AParent: TPanel);
begin
  if assigned(AFrame) then
  begin
    AFrame.Parent := AParent;
    AFrame.Align := alClient;
  end;
end;


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