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Add not-quite-working graphics polymophism demo

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This commit is contained in:
Timothy Warren 2021-10-06 11:33:12 -04:00
parent 1169375c4e
commit 010d124826
6 changed files with 261 additions and 0 deletions
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56
drawing demo/drawing.pas Normal file
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unit drawing;
{$mode objfpc}{$H+}
interface
uses
Classes, SysUtils, Controls, ExtCtrls, Graphics;
type TDrawing = class(TGraphicControl)
private
FExtent: integer;
public
constructor Create(theOwner: TComponent; anExtent: integer);
property Extent: integer read FExtent write FExtent;
end;
TSquare = class(TDrawing)
public
procedure Paint; override;
end;
TCircle = class(TDrawing)
public
procedure Paint; override;
end;
implementation
constructor TDrawing.Create(theOwner: TComponent; anExtent: integer);
begin
inherited Create(theOwner);
FExtent := anExtent;
Width := FExtent;
Height := FExtent;
end;
{TCircle}
procedure TCircle.Paint;
begin
Canvas.Brush.Color := clBtnFace;
Canvas.FillRect(0, 0, FExtent, FExtent);
Canvas.Brush.Color := clYellow;
Canvas.Ellipse(0, 0, FExtent, FExtent);
end;
{TSquare}
procedure TSquare.Paint;
begin
Canvas.Brush.Color := clSilver;
Canvas.FillRect(0, 0, FExtent, FExtent);
Canvas.Rectangle(0, 0, FExtent, FExtent);
end;
end.

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drawing demo/drawingdemo.ico Normal file
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drawing demo/drawingdemo.lpi Normal file
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<?xml version="1.0" encoding="UTF-8"?>
<CONFIG>
<ProjectOptions>
<Version Value="11"/>
<General>
<SessionStorage Value="InProjectDir"/>
<MainUnit Value="0"/>
<Title Value="drawingdemo"/>
<Scaled Value="True"/>
<ResourceType Value="res"/>
<UseXPManifest Value="True"/>
<XPManifest>
<DpiAware Value="True"/>
</XPManifest>
<Icon Value="0"/>
</General>
<BuildModes Count="1">
<Item1 Name="Default" Default="True"/>
</BuildModes>
<PublishOptions>
<Version Value="2"/>
<UseFileFilters Value="True"/>
</PublishOptions>
<RunParams>
<FormatVersion Value="2"/>
<Modes Count="0"/>
</RunParams>
<RequiredPackages Count="1">
<Item1>
<PackageName Value="LCL"/>
</Item1>
</RequiredPackages>
<Units Count="3">
<Unit0>
<Filename Value="drawingdemo.lpr"/>
<IsPartOfProject Value="True"/>
</Unit0>
<Unit1>
<Filename Value="drawingdisplay.pas"/>
<IsPartOfProject Value="True"/>
<ComponentName Value="Form1"/>
<ResourceBaseClass Value="Form"/>
</Unit1>
<Unit2>
<Filename Value="drawing.pas"/>
<IsPartOfProject Value="True"/>
</Unit2>
</Units>
</ProjectOptions>
<CompilerOptions>
<Version Value="11"/>
<Target>
<Filename Value="drawingdemo"/>
</Target>
<SearchPaths>
<IncludeFiles Value="$(ProjOutDir)"/>
<UnitOutputDirectory Value="lib/$(TargetCPU)-$(TargetOS)"/>
</SearchPaths>
<Linking>
<Debugging>
<DebugInfoType Value="dsDwarf2Set"/>
</Debugging>
<Options>
<Win32>
<GraphicApplication Value="True"/>
</Win32>
</Options>
</Linking>
</CompilerOptions>
<Debugging>
<Exceptions Count="3">
<Item1>
<Name Value="EAbort"/>
</Item1>
<Item2>
<Name Value="ECodetoolError"/>
</Item2>
<Item3>
<Name Value="EFOpenError"/>
</Item3>
</Exceptions>
</Debugging>
</CONFIG>

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drawing demo/drawingdemo.lpr Normal file
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program drawingdemo;
{$mode objfpc}{$H+}
uses
{$IFDEF UNIX}{$IFDEF UseCThreads}
cthreads,
{$ENDIF}{$ENDIF}
Interfaces, // this includes the LCL widgetset
Forms,
Controls,
Graphics,
ExtCtrls,
drawing,
drawingdisplay;
{$R *.res}
begin
RequireDerivedFormResource:=True;
// Application.Scaled:=True;
Application.Initialize;
Application.CreateForm(TForm1, Form1);
Application.Run;
end.

34
drawing demo/drawingdisplay.lfm Normal file
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object Form1: TForm1
Left = 627
Height = 240
Top = 322
Width = 320
Caption = 'Polymorphic drawing example'
ClientHeight = 240
ClientWidth = 320
OnCreate = FormCreate
LCLVersion = '2.0.12.0'
object rgShape: TRadioGroup
Left = 41
Height = 68
Top = 141
Width = 239
AutoFill = True
Caption = 'Type of FDrawing'
ChildSizing.LeftRightSpacing = 6
ChildSizing.EnlargeHorizontal = crsHomogenousChildResize
ChildSizing.EnlargeVertical = crsHomogenousChildResize
ChildSizing.ShrinkHorizontal = crsScaleChilds
ChildSizing.ShrinkVertical = crsScaleChilds
ChildSizing.Layout = cclLeftToRightThenTopToBottom
ChildSizing.ControlsPerLine = 1
ClientHeight = 49
ClientWidth = 229
Items.Strings = (
'TSquare'
'TCircle'
)
OnClick = rgShapeClick
TabOrder = 0
end
end

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drawing demo/drawingdisplay.pas Normal file
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unit drawingdisplay;
{$mode objfpc}{$H+}
interface
uses
Classes, SysUtils, Forms, Controls, Graphics, Dialogs, ExtCtrls, drawing;
type
{ TForm1 }
TForm1 = class(TForm)
procedure FormCreate(Sender: TObject);
procedure rgShapeClick(Sender: TObject);
private
rgShape: TRadioGroup;
FDrawing: TDrawing;
procedure CreateANewDrawing;
public
end;
const extent = 50;
var
Form1: TForm1;
implementation
procedure TForm1.CreateANewDrawing;
begin
if (rgShape.ItemIndex < 0) then Exit;
FDrawing.Free;
case rgShape.ItemIndex of
0: begin
FDrawing := TSquare.Create(Self, extent);
FDrawing.Left := 10;
end;
1: begin
FDrawing := TCircle.Create(Self, extent);
FDrawing.Left := 60;
end;
end;
FDrawing.Top := 10;
FDrawing.Parent := Self;
end;
procedure TForm1.FormCreate(Sender: TObject);
begin
CreateANewDrawing;
end;
procedure TForm1.rgShapeClick(Sender: TObject);
begin
CreateANewDrawing;
end;
{$R *.lfm}
end.