MDI a kreslenie

// ............................................................................
procedure Kresli_pozadie_formu(Sender: TObject);

var
    x, y: Integer;

begin
    if (BitMapPozadie.Width > 0) and (BitMapPozadie.Height > 0) then
       begin
         y := 0;
         while y < (Sender as TForm).Height do
            begin
               x := 0;
               while x < (Sender as TForm).Width do
                  begin
                     (Sender as TForm).Canvas.Draw(x, y, BitMapPozadie);
                      x := x + BitMapPozadie.Width;
                  end;
               y := y + BitMapPozadie.Height;
            end;
       end;
end;

unit Kopirovanie_suborov;
{
 Formular  Form_vyber_suborov je MDI

}

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls;

type
  TMainForm = class(TForm)
    btKopiruj: TButton;
    btVyber_suborov: TButton;
    btVyber_adresara: TButton;
    lbxZoznam_suborov: TListBox;
    Label1: TLabel;
    btKoniec: TButton;
    procedure FormCreate(Sender: TObject);
    procedure btVyber_suborovClick(Sender: TObject);
    procedure FormPaint(Sender: TObject);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure btKoniecClick(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;


procedure Kresli_pozadie_formu(Sender: TObject);

var
  MainForm: TMainForm;
  BitMapPozadie: TBitmap;    // bitmapa pozadia formulara

implementation

uses Vyber_suborov;


{$R *.DFM}


// ........................................................................
procedure TMainForm.FormCreate(Sender: TObject);
var
   Subor_bmp : String;
begin


// urcenie cesty podla umiestnenia exe suboru
   Subor_bmp := ExtractFilePath(Application.ExeName)+ 'bor6.bmp';

// nacitanie bitmapy pozadie ak je pritomny subor bor6.bmp
   BitmapPozadie := TBitmap.Create;
   if FileExists(Subor_bmp) then
      begin
         BitmapPozadie.LoadFromFile(Subor_bmp);
      end
   else
      Application.MessageBox(PChar('Neexistuje súbor ' + Subor_bmp + ' '),
            'Neprítomný súbor !! ', mb_OK);
end;

// ...........................................................................
procedure TMainForm.btVyber_suborovClick(Sender: TObject);
begin
    if Form_vyber_suborov = nil then
       Form_vyber_suborov:=TForm_vyber_suborov.Create(self);

    with Form_vyber_suborov do
       begin
            Left:=MainForm.Left + 30;
            Top:=MainForm.Top - 165;
            Height:= 300;
            Width := 580;
            Show;
       end;

end;

// ............................................................................
procedure Kresli_pozadie_formu(Sender: TObject);

var
    x, y: Integer;

begin
    if (BitMapPozadie.Width > 0) and (BitMapPozadie.Height > 0) then
       begin
         y := 0;
         while y < (Sender as TForm).Height do
            begin
               x := 0;
               while x < (Sender as TForm).Width do
                  begin
                     (Sender as TForm).Canvas.Draw(x, y, BitMapPozadie);
                      x := x + BitMapPozadie.Width;
                  end;
               y := y + BitMapPozadie.Height;
            end;
       end;
end;

// .........................................................................
procedure TMainForm.FormPaint(Sender: TObject);
begin
   Kresli_pozadie_formu(Sender);
end;


// .........................................................................
procedure TMainForm.FormClose(Sender: TObject; var Action: TCloseAction);
begin
   BitmapPozadie.Free;
end;

// ...........................................................................
procedure TMainForm.btKoniecClick(Sender: TObject);
begin
   Close;
end;

end.

implementation

{$R *.dfm}

uses Unit3;

procedure TForm2.Button1Click(Sender: TObject);
begin

  // zmeni text vo Form3, ktory ma formStyle fsMDIChild
  Form3.Label1.Caption := 'Zmena textu';

end;

implementation

{$R *.dfm}

uses Unit2;

procedure TForm3.Button1Click(Sender: TObject);
begin

  // zmeni text vo Form2, ktory ma formStyle fsMDIChild
  Form2.Label1.Caption := 'zmena textu';

end;

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TMainForm = class(TForm)
    Button1: TButton;
    Label1: TLabel;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  MainForm: TMainForm;

implementation

uses Unit2;

{$R *.dfm}

procedure TMainForm.Button1Click(Sender: TObject);
begin
    if Form2 = nil then
       Form2:=TForm2.Create(self);

    with Form2 do
       begin
            Left:=MainForm.Left + 60;
            Top:=MainForm.Top - 145;
            Height:= 300;
            Width := 580;
            Show;
       end;

end;

end.



unit Unit2;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TForm2 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form2: TForm2;

implementation

uses Unit1;

{$R *.dfm}


procedure TForm2.FormClose(Sender: TObject; var Action: TCloseAction);
begin
  Action := caFree;
end;

procedure TForm2.Button1Click(Sender: TObject);
begin
   MainForm.Label1.Visible := true;
   MainForm.Label1.Caption :='visible';
end;

procedure TForm2.Button2Click(Sender: TObject);
begin
//   MainForm.Label1.Visible := false;
      MainForm.Label1.Caption :='unvisible'
end;

procedure TForm2.FormDestroy(Sender: TObject);
begin
   Form2 := nil;
end;

end.