/*
The following example enables the user to move the current
selected cell in a db grid.  The Up and Down buttons have
their OnClick events assigned to the UpDownClick procedure.
The Left and Right buttons have their OnClick events
assigned to the LeftRightClick procedure.  The Up and Left
buttons have their Tag property set to -1, while the Down
and Right buttons have their Tag property set to 1.  MoveBy
does not move the cell in the db grid, it only moves the
selection.  The data set is not edited.  Notice that the
Up button and the Down button are separate TButtons, not
one TUpDown.  The tags must be set different.
*/
void __fastcall TForm1::UpDownClick(TObject *Sender)
{
  CDS2->MoveBy((dynamic_cast<TComponent *>(Sender))->Tag);
  DBGrid2->SetFocus();
}

void __fastcall TForm1::LeftRightClick(TObject *Sender)
{
  DBGrid2->SelectedIndex = DBGrid2->SelectedIndex + (dynamic_cast<TComponent *>(Sender))->Tag;
  DBGrid2->SetFocus();
}

/*
This example demonstrates how to add and delete menu items
to a popup menu at runtime and assign an event handler to
the OnClick event.  Place a TPopupMenu and three buttons on
the form named "AddButton", "EditButton",  and
"DestroyButton" and add OnClick events to all three buttons.
Put the TPopupMenu in the PopupMenu property of the form.
Place the PopupMenuItemsClick procedure in the TForm1 type
declaration so that it can be used as the method call for
the menu item OnClick event.
*/
void __fastcall TForm1::AddButtonClick(TObject *Sender)
{
    // The owner (PopupMenu1) will cleanup this menu item.
    TMenuItem *NewItem = new TMenuItem(PopupMenu1); // create the new item
    int index = PopupMenu1->Items->Count;
    PopupMenu1->Items->Add(NewItem);// add it to the Popupmenu
    NewItem->Caption = "Menu Item " + IntToStr(index);
    NewItem->Tag = index;
    NewItem->OnClick = PopupMenuItemsClick;// assign it an event handler
    TNotifyEvent();
}

void __fastcall TForm1::PopupMenuItemsClick(TObject *Sender)
{
    TMenuItem *ClickedItem = dynamic_cast<TMenuItem *>(Sender);
    if (ClickedItem)
    {
        switch (ClickedItem->Tag)
        {
            case 0:
            {
                ShowMessage("first item clicked");
                break;
            }
            case 1:
            {
                ShowMessage("second item clicked");
                break;
            }
            case 2:
            {
                ShowMessage("third item clicked");
                break;
            }
            case 3:
            {
                ShowMessage("fourth item clicked");
                break;
            }
        }
    }
}

/*
To edit or destroy an item, grab its pointer via the Items
property.
*/
void __fastcall TForm1::EditButtonClick(TObject *Sender)
{
    const int index = 1;
    TMenuItem *ItemToEdit = PopupMenu->Items->Items[index];
    ItemToEdit->Caption = "Changed Caption";
}

void __fastcall TForm1::DestroyButtonClick(TObject *Sender)
{
    const int index = 2;
    TMenuItem *ItemToDelete = PopupMenu->Items->Items[index];
    delete ItemToDelete;
}

void __fastcall TForm1::FormCreate(TObject *Sender)
{
    const int num_items = 4;
    for (int index = 0; index < num_items; ++index)
    {
        // The owner (PopupMenu1) will cleanup this menu item.
        TMenuItem *NewItem = new TMenuItem(PopupMenu1); // create the new item
        PopupMenu1->Items->Add(NewItem);// add it to the Popupmenu
        NewItem->Caption = "Menu Item " + IntToStr(index);
        NewItem->Tag = index;
        NewItem->OnClick = PopupMenuItemsClick;// assign it an event handler
        TNotifyEvent();
    }
}

{
The following example enables the user to move the current
selected cell in a db grid.  The Up and Down buttons have
their OnClick events assigned to the UpDownClick procedure.
The Left and Right buttons have their OnClick events
assigned to the LeftRightClick procedure.  The Up and Left
buttons have their Tag property set to -1, while the Down
and Right buttons have their Tag property set to 1.  MoveBy
does not move the cell in the db grid, it only moves the
selection.  The data set is not edited.  Notice that the
Up button and the Down button are separate TButtons, not
one TUpDown.  The tags must be set different.
}
procedure TForm1.UpDownClick(Sender: TObject);
begin
  CDS.MoveBy(TComponent(Sender).Tag);
  DBGrid1.SetFocus;
end;

procedure TForm1.LeftRightClick(Sender: TObject);
begin
  DBGrid1.SelectedIndex := DBGrid1.SelectedIndex + TComponent(Sender).Tag;
  DBGrid1.SetFocus;
end;

{
This example demonstrates how to add and delete menu items
to a popup menu at runtime and assign an event handler to
the OnClick event.  Place a TPopupMenu and three buttons on
the form named "AddButton", "EditButton",  and
"DestroyButton" and add OnClick events to all three buttons.
Put the TPopupMenu in the PopupMenu property of the form.
Place the PopupMenuItemsClick procedure in the TForm1 type
declaration so that it can be used as the method call for
the menu item OnClick event.
}

type
  TForm1 = class(TForm)
    AddButton: TButton;
    EditButton: TButton;
    DestroyButton: TButton;
    PopupMenu1: TPopupMenu;
    procedure AddButtonClick(Sender: TObject);
    procedure EditButtonClick(Sender: TObject);
    procedure DestroyButtonClick(Sender: TObject);
    procedure FormCreate(Sender: TObject);
  private
    { Private declarations }
  public
    procedure PopupMenuItemsClick(Sender: TObject);

  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.AddButtonClick(Sender: TObject);
var
  index: Integer;
  NewItem: TMenuItem;
begin
    // The owner (PopupMenu1) will cleanup this menu item.
  NewItem := TMenuItem.Create(PopupMenu1); // create the new item
  index := PopupMenu1.Items.Count;
  PopupMenu1.Items.Add(NewItem);// add it to the Popupmenu
  NewItem.Caption := 'Menu Item ' + IntToStr(index);
  NewItem.Tag := index;
  NewItem.OnClick :=
    PopupMenuItemsClick; // assign it an event handler
end;

procedure TForm1.PopupMenuItemsClick(Sender: TObject);
begin
  with Sender as TMenuItem do
  begin
    case Tag of
      0:  ShowMessage('first item clicked');
      1:  ShowMessage('second item clicked');
      2:  ShowMessage('third item clicked');
      3:  ShowMessage('fourth item clicked');
    end;
  end;
end;

{
To edit or destroy an item, grab its pointer via the Items
property.
}
procedure TForm1.EditButtonClick(Sender: TObject);
var
  ItemToEdit: TMenuItem;
begin
  ItemToEdit := PopupMenu.Items[1];
  ItemToEdit.Caption := 'Changed Caption';
end;

procedure TForm1.DestroyButtonClick(Sender: TObject);
var
  ItemToDelete: TMenuItem;
begin
  ItemToDelete := PopupMenu.Items[2];
  ItemToDelete.Free;
end;

procedure TForm1.FormCreate(Sender: TObject);
var
  index: Integer;
  NewItem: TMenuItem;
begin
  for index := 0 to 3 do
  begin
      // The owner (PopupMenu1) will cleanup this menu item.
    NewItem := TMenuItem.Create(PopupMenu1); // create the new item
    PopupMenu1.Items.Add(NewItem);// add it to the Popupmenu
    NewItem.Caption := 'Menu Item ' + IntToStr(index);
    NewItem.Tag := index;
    NewItem.OnClick :=
      PopupMenuItemsClick; // assign it an event handler
  end;
end;