Delphi Tips & Trick

{ Fill bitmap to Form } unit Unit1; interface uses Windows, Classes, SysUtils, Graphics, Forms; type TRGBArray = array [0..32767] of TRGBTriple; PRGBArray = ^TRGBArray; type TForm1 = class (TForm) procedure FormCreate(Sender: TObject); procedure FormDestroy(Sender: TObject); private { Private declarations } FRegion: THandle; function CreateRegion(Bmp: TBitmap): THandle; end ; var Form1: TForm1; implementation {$R *.dfm} function TForm1.CreateRegion(Bmp: TBitmap): THandle; var X, Y, StartX: Integer; Excl: THandle; Row: PRGBArray; TransparentColor: TRGBTriple; begin Bmp.PixelFormat := pf24Bit; Result := CreateRectRGN(0, 0, Bmp.Width, Bmp.Height); for Y := 0 to Bmp.Height - 1 do begin Row := Bmp.Scanline[Y]; StartX := -1; if Y = 0 then TransparentColor := Row[0]; for X := 0 to Bmp.Width - 1 do begin if (Row[X].rgbtRed = TransparentColor.rgbtRed) and (Row[X].rgbtGreen = TransparentColor.rgbtGreen) and

{ Delphi Tips This code gives the key the same habbit as the key to change focus between Controls. } // Form1.KeyPreview := True ! procedure TForm1.FormKeyPress(Sender: TObject; var Key: Char); begin if Key = #13 then begin Key := #0; { check if SHIFT - Key is pressed } if GetKeyState(VK_Shift) and $8000 <> 0 then PostMessage(Handle, WM_NEXTDLGCTL, 1, 0) else PostMessage(Handle, WM_NEXTDLGCTL, 0, 0); end ; end ; swissdelphicenter.ch

procedure TForm1.Button1Click(Sender: TObject); begin if (fsModal in FormState) then ShowMessage('Form is modal.'); end ; swissdelphicenter.ch

The following example demonstrates using DDE to execute Explorer's find file dialog. The example opens the dialog in the Directory "C:\DelphiTips". ~~~~~~~~~~~~~~~~~~~~~~~~~ uses ddeman; procedure TForm1.Button1Click(Sender: TObject) ; begin with TDDEClientConv.Create(Self) do begin ConnectMode := ddeManual; ServiceApplication := 'explorer.exe'; SetLink( 'Folders', 'AppProperties') ; OpenLink; ExecuteMacro ('[FindFolder(, C:\DelphiTips)]', False) ; CloseLink; Free; end; end; About.com

Add a Button (Button1) to a Delphi form (Form1) procedure TForm1.FormCreate(Sender: TObject) ; var FullRgn, ClientRgn, ButtonRgn: THandle; Margin, X, Y: Integer; begin Margin := (Width - ClientWidth) div 2; FullRgn := CreateRectRgn(0, 0, Width, Height) ; X := Margin; Y := Height - ClientHeight - Margin; ClientRgn := CreateRectRgn (X, Y, X + ClientWidth, Y + ClientHeight) ; CombineRgn(FullRgn, FullRgn, ClientRgn, RGN_DIFF) ; X := X + Button1.Left; Y := Y + Button1.Top; ButtonRgn := CreateRectRgn (X, Y, X + Button1.Width, Y + Button1.Height) ; CombineRgn(FullRgn, FullRgn, ButtonRgn, RGN_OR) ; SetWindowRgn(Handle, FullRgn, True) ; end; from: about.com