FMX Show and Hide MainMenu from code

[CRO_Tomislav 0]

Dear all.

 

I am trying to migrate from Delphi VCL to Delphi Firemonky application.

In VCL I am using several ManiMenus.

 

In VCL form, on Show I have:

Form_main.Menu := nil;

Also in VCL, depending on which button is pressed I load certain MainMenu

Form_main.Menu := MainMenu_Parts;

 

I stuck in FMX with this because it handle MainMenu totally different. How I can do the same in FMX?

 

Thanks in advance

Tomislav

[CRO_Tomislav 0]

Hi.

 

I achieve the same effect by replacing MainMenu with MenuBar and set a Menubr.Visible := False and True.

 

Is this OK or there is some elegant non complicated solution? 8)

 

With best regards

Tomislav

 

[Guest]

in FMX, you can have just 1 MainMenu for all application!

a possibility is create all items and childrens for all forms, and set the "visible" only for menuitem necessary in each form used!
Then, that way, it's not necessary have a "clone" of old menu! Else, you can store this MainMenu for "when" close new form, re-create it or re-show the hide items!

 

some like this:

// main-form
var
  lMainMenuObj: TMainMenu = nil; // this will be our MainMenu for all app!
...
implementation
...

///----- prcMyLogMemo = my procedure to "Memo1.Lines.Add( xxxx );"

procedure TfrmFormMain.btnVerifyingOrAssigningAMainMenuToAppClick(Sender: TObject);
begin
  try
    if not(Self.MainMenu = nil) then
      prcMyLogMemo(Format('The MainMenu.Name is [%s]', [Self.MainMenu.Name]))
    else
    begin
      if (lMainMenuObj = nil) then
      begin
        lMainMenuObj      := TMainMenu.Create(Self); // owner! ... creating my MainMenu by code
        lMainMenuObj.Name := 'mmnuMyMainMenuForAppWhole';
        // *********************************************************************************
        // "parent" property, do the magic happens!
        // when defining the "parent" you are "attributing" your "MainMenu" for your form!
        // then, Self.MainMenu will be assigned!
        // remember: Only one MainMenu is accepted in your app!
        // *********************************************************************************
        //
        lMyMenuItem         := TMenuItem.Create(lMainMenuObj);
        lMyMenuItem.Name    := Format('MMItem%d', [TMainMenu(Self.MainMenu).ItemsCount + 1]);
        lMyMenuItem.Text    := lMyMenuItem.Name;
        lMyMenuItem.OnClick := prcMyMenuItemsClick;
        //
        lMainMenuObj.AddObject(lMyMenuItem); // adding the Items to MainMenu 
        //
        prcMyLogMemo(Format('MainMenu [%s] was created and first MenuItem = [%s] was added on MainMenu', { }
          [lMainMenuObj.Name, lMyMenuItem.Name]));
        //
        lMyMenuItem := nil; // maybe it's not necessary if it was "local" in this procedure!
		//
        lMainMenuObj.Parent := Self; // now, we are defining "who" will be our "MainMenu" // let it for last command-line! when all is defined ok?
      end
      else
        prcMyLogMemo('(lMainMenu=nil) and (lMainMenuObj.Name=' + lMainMenuObj.Name);
    end;
  except
    on e: exception do
      ShowMessage(e.Message);
  end;
end;

procedure TfrmFormMain.btnCreatingSecondFormClick(Sender: TObject);
var
  lMyFormSecond: TfrmFormSecondTests;
begin
  {
    a possibility is create all items and childres for all forms, and set the "visible" only for
    menuitem necessary in each form used!
    Then, that way, it's not necessary have a "clone" of old menu!
  }
  if not(lMainMenuObj = nil) then
  begin
    lBkpMainMenu := lMainMenuObj; // dont works like expected! It's just a "pointer", not a "copy of object"
    ShowMessage(lMainMenuObj.Name + ', entering in FormSecond');
  end;
  //
  lMyFormSecond := TfrmFormSecondTests.Create(nil);
  try
   // now, in FormSecond, I can destroy or hide the items not necessary or any other thing... in my sample, when I came back... the MainMenu was destroyed by FormSecond.destoy event
    lMyFormSecond.ShowModal;
  finally
    FreeAndNil(lMyFormSecond);
  end;
  //
  // as our MainMenu as "destroyed" in FormSecond, let's re-create again!
  // as the Items was not cleaned, then, it's not necessary recreat it!
  if not(lBkpMainMenu = nil) then
  begin
    ShowMessage('came back from FormSecond');
    //
    // lMainMenuObj        := TMainMenu.Create(Self); // owner!
    // lMainMenuObj.Parent := Self;
    ... recreating the MainMenu or just enable its hide "Items"
  end;
end;

 

var
  frmFormSecondTests: TfrmFormSecondTests;

implementation

{$R *.fmx}

uses
  // System.Generics.Collections,
  uFormMainTests;

var
  lBackupMainMenuObj: TMainMenu;
  lNewMainMenuObj   : TMainMenu;
  lMyMenuItem       : TMenuItem;
  //
  lMyMenuBarClone: TMenuBar;

procedure TfrmFormSecondTests.btnDestroyMainMenuAndCreateANewMainMenuClick(Sender: TObject);
begin
  if (not(lMainMenuObj = nil)) and (lMainMenuObj is TMainMenu) then
  begin
    ShowMessage((lMainMenuObj as TMainMenu).Name);
    //
    // If you needs create a new MainMenu, then, you need "destroy" older in use!
    // all items will be destroyed too!
    (lMainMenuObj as TMainMenu).Free;
    lMainMenuObj := nil;
    ShowMessage('menu main destruido');
    //
    //
    lNewMainMenuObj      := TMainMenu.Create(self); // owner!
    lNewMainMenuObj.Name := 'NewmmnuMyMainMenuForAppWhole';
    // *********************************************************************************
    // "parent" property, do the magic happens!
    // when defining the "parent" you are "attributing" your "MainMenu" for your form!
    // then, Self.MainMenu will be assigned!
    // remember: Only one MainMenu is accepted in your app!
    lNewMainMenuObj.Parent := self; // now, we are defining "who" will be our "MainMenu"
    // *********************************************************************************
    //
    lMyMenuItem      := TMenuItem.Create(lNewMainMenuObj);
    lMyMenuItem.Name := Format('NewMMItem%d', [TMainMenu(self.MainMenu).ItemsCount + 1]);
    lMyMenuItem.Text := lMyMenuItem.Name;
    //
    lNewMainMenuObj.AddObject(lMyMenuItem);

  end;
end;

procedure TfrmFormSecondTests.CloseThisFormClick(Sender: TObject);
begin
  if (not(lNewMainMenuObj = nil)) and (lNewMainMenuObj is TMainMenu) then
  begin
    ShowMessage((lNewMainMenuObj as TMainMenu).Name);
    //
    // if you need use older MainMenu, you need "destroy" the current MainMenu!
    (lNewMainMenuObj as TMainMenu).Free;
    lNewMainMenuObj := nil;
    //
    ShowMessage('menu main form2 destruido');
    //
    if not(lBkpMainMenu = nil) then
      ShowMessage(lBkpMainMenu.ItemsCount.ToString + ', voltando do formsecond');
    //
    close;
  end;
end;

procedure TfrmFormSecondTests.FormDestroy(Sender: TObject);
begin
  if not(lMyMenuBarClone = nil) then
    lMyMenuBarClone.Free;
end;

 

Edited November 15, 2020 by Guest