source: DpiControls/Demo/UDpiFormMain.pas

unit UDpiFormMain;

{$mode objfpc}{$H+}

interface

uses
  Classes, SysUtils, Dpi.Controls, Dpi.ExtCtrls, Dialogs, Dpi.Graphics, Dpi.Forms,
  Types;

type

  { TDpiFormMain }

  TDpiFormMain = class(TForm)
    DpiPaintBox1: TPaintBox;
    procedure DpiButton1Click(Sender: TObject);
    procedure DpiFormMainCreate(Sender: TObject);
    procedure DpiFormMainDestroy(Sender: TObject);
    procedure DpiPaintBox1Paint(Sender: TObject);
  private
    Button: TButton;
    ButtonClose: TButton;
    Image: TImage;
    ListBox: TListBox;
    PaintBox: TPaintBox;
    Bitmap: TBitmap;
    procedure ButtonCloseClick(Sender: TObject);
  public
  end;

var
  DpiFormMain: TDpiFormMain;

implementation

{$R *.lfm}

{ TDpiFormMain }

procedure TDpiFormMain.DpiFormMainCreate(Sender: TObject);
var
  I: Integer;
  X, Y: Integer;
begin
  Button := TDpiButton.Create(DpiFormMain);
  Button.Parent := Self;
  Button.SetBounds(10, 10, 100, 30);
  Button.Caption := 'Click me';
  Button.Visible := True;
  Button.OnClick := @DpiButton1Click;

  ButtonClose := TDpiButton.Create(DpiFormMain);
  ButtonClose.Parent := Self;
  ButtonClose.SetBounds(120, 10, 100, 30);
  ButtonClose.Caption := 'Close';
  ButtonClose.Visible := True;
  ButtonClose.OnClick := @ButtonCloseClick;

  Image := TDpiImage.Create(DpiFormMain);
  Image.Parent := Self;
  Image.SetBounds(150, 10, 100, 100);
  Image.Visible := True;
  Image.Stretch := True;
  Image.VclImage.Picture.LoadFromFile('dance.jpg');
  //Image.Picture.LoadFromFile('dance.jpg');

  ListBox := TDpiListBox.Create(DpiFormMain);
  for I := 0 to 10 do
    ListBox.VclListBox.Items.Add('Item ' + IntToStr(I));
  ListBox.Parent := Self;
  ListBox.SetBounds(250, 10, 100, 100);
  ListBox.Visible := True;

  PaintBox := TDpiPaintBox.Create(DpiFormMain);
  PaintBox.Parent := Self;
  PaintBox.BoundsRect := Bounds(0, 100, 200, 200);
  PaintBox.OnPaint := @DpiPaintBox1Paint;
  PaintBox.Visible := True;

  Bitmap := TDpiBitmap.Create;
  Bitmap.PixelFormat := pf24bit;
  Bitmap.SetSize(120, 50);
  for Y := 0 to Bitmap.Height - 1 do
    for X := 0 to Bitmap.Width - 1 do
      Bitmap.Canvas.Pixels[X, Y] := X mod 255;
  Bitmap.LoadFromFile('dance.bmp');
end;

procedure TDpiFormMain.DpiFormMainDestroy(Sender: TObject);
begin
  FreeAndNil(Button);
  FreeAndNil(Image);
  FreeAndNil(ListBox);
end;

procedure TDpiFormMain.DpiPaintBox1Paint(Sender: TObject);
var
  X, Y: Integer;
begin
  with PaintBox.Canvas do begin
    Brush.Color := clWhite;
    Brush.Style := bsSolid;
    FillRect(Bounds(0, 0, PaintBox.Width, PaintBox.Height));
    Caption := IntToStr(Width);
    Pen.Color := clGreen;
    Pen.Style := psSolid;
    MoveTo(0, 0);
    LineTo(100, 100);
    Font.Color := clRed;
    Font.Size := 20;
    TextOut(10, 10, 'Scaled text');

    Brush.Color := clBlue;
    Rectangle(Bounds(20, 30, 60, 30));

    Bitmap.Dpi := DpiScreen.Dpi;
    DpiBitBltCanvas(PaintBox.Canvas, 0, 0, Bitmap.Width, Bitmap.Height, Bitmap.Canvas, 0, 0);
  end;
end;

procedure TDpiFormMain.ButtonCloseClick(Sender: TObject);
begin
  ModalResult := mrOk;
end;

procedure TDpiFormMain.DpiButton1Click(Sender: TObject);
var
  DpiForm: TDpiForm;
begin
  //ShowMessage('Hello');
  DpiForm := TDpiFormMain.CreateNew(Self);
  DpiForm.Name := 'Form10';
  DpiForm.Caption := 'Modal form';
  DpiForm.SetBounds(200, 150, 400, 200);
  DpiForm.ShowModal;
end;

end.