Want to protect your cyber security and still get fast solutions? Ask a secure question today.Go Premium

x
  • Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 613
  • Last Modified:

why drawfocusrect can'nt work to image?

hi.
  experts!i have some question in drawfocusrect,when a timage have assigned a picture these code can'nt work.
help!thanks!
       
unit Unitdrawfocusrect;

interface

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

type
  TForm1 = class(TForm)
    Image1: TImage;
    procedure Image1MouseDown(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
    procedure Image1MouseUp(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
    procedure Image1MouseMove(Sender: TObject; Shift: TShiftState; X,
      Y: Integer);
  private
    { Private declarations }
    MyPoint:TPoint;
    FDrawing:boolean;
    MyDrawRect:TRect;
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Image1MouseDown(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  FDrawing:=true;
  MyDrawRect.Left:=X;
  MyDrawRect.Top:=Y;
  MyDrawRect.BottomRight:=MyDrawRect.TopLeft;
  MyPoint:=point(X,Y);
  drawfocusrect(image1.Picture.Bitmap.Canvas.Handle,MyDrawRect);
// image1.picture.bitmap.Canvas.DrawFocusRect(MyDrawRect);

end;

procedure TForm1.Image1MouseUp(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
   FDrawing:=false;
   drawfocusrect(image1.Picture.Bitmap.Canvas.Handle,MyDrawRect);
// image1.picture.bitmap.Canvas.DrawFocusRect(MyDrawRect);

end;

procedure TForm1.Image1MouseMove(Sender: TObject; Shift: TShiftState; X,
  Y: Integer);
begin
   if  FDrawing=true then
   begin
// image1.picture.bitmap.Canvas.DrawFocusRect(MyDrawRect);

    drawfocusrect(image1.Picture.Bitmap.Canvas.Handle,MyDrawRect);
        if X>MyPoint.X then
        begin
            MyDrawRect.Left:=MyPoint.X;
            MyDrawRect.Right:=X;
        end
             else
        begin
            MyDrawRect.Left:=X;
            MyDrawRect.Right:=MyPoint.X
        end;
        if Y>MyPoint.Y then
        begin
           MyDrawRect.Top:=MyPoint.Y;
           MyDrawRect.Bottom:=Y;
        end
             else
        begin
           MyDrawRect.Top:=Y;
           MyDrawRect.Bottom:=MyPoint.Y
        end;
        Drawfocusrect(image1.Picture.Bitmap.Canvas.Handle,MyDrawrect);
// image1.picture.bitmap.Canvas.DrawFocusRect(MyDrawRect);

    end;
end;
end.
 
0
jbas
Asked:
jbas
  • 3
  • 2
1 Solution
 
FractionCommented:
Why can't you use the TCanvas.DrawFocusRect as disabled in your example?
0
 
jbasAuthor Commented:
thanks,
       use tcanvas.drawfocusrect or drawfocusrect(tcanvas.handle,r) all can'nt work well while a image assigned a picture.
     i want to zoom out/in the region focused,but that code can'nt work.so i need help.
  thanks.
0
 
DrDelphiCommented:
Draw the focus rectangle on the form's canvas instead. For example:


var rec:Trect;
begin
 rec:=Rect(0,0,100,100);
 drawfocusrect(image1.canvas.handle,rec); ///does NOT work
end;

//---------------------------------------------------
var rec:Trect;
begin
 rec:=Rect(image1.left,image1.top,100,100);
 drawfocusrect(self.canvas.handle,rec);//WORKS a charm!
end;


Good luck!!






0
Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 
jbasAuthor Commented:
thanks.
you method can work well,later i will give you the points if the region can zoom in/out(can you help me too?:))
0
 
FractionCommented:
Try something like this:

procedure TForm1.Image1MouseUp(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
var
  Bmp: TBitmap;
begin
  FDrawing:=false;
  drawfocusrect(self.canvas.handle, MyDrawRect);
  Bmp := TBitmap.Create;
  Bmp.Width := MyDrawRect.Right-MyDrawRect.Left;
  Bmp.Height := MyDrawRect.Bottom-MyDrawRect.Top;
  Bmp.Canvas.CopyRect(Rect(0, 0, Bmp.Width, Bmp.Height),image1.Picture.Bitmap.Canvas, MyDrawRect);
  image1.Picture.Bitmap.Canvas.StretchDraw(Rect(0, 0, image1.Width, image1.Height), Bmp);
  Bmp.Free;
end;
0
 
jbasAuthor Commented:
thanks to Fraction and DrDelphi !
to Fraction :
please talk the points in here.
http://www.experts-exchange.com/jsp/qManageQuestion.jsp?ta=delphi&qid=20306972
0

Featured Post

Concerto Cloud for Software Providers & ISVs

Can Concerto Cloud Services help you focus on evolving your application offerings, while delivering the best cloud experience to your customers? From DevOps to revenue models and customer support, the answer is yes!

Learn how Concerto can help you.

  • 3
  • 2
Tackle projects and never again get stuck behind a technical roadblock.
Join Now