Moving/dragging TPanel in TForm
lazarus / 31-LCL

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asdf · 2010-10-30 11:58

I have made a calculator, all buttons and displays are on a TPanel.
I'd like the user can move/drag to some place they may need.
But I could not do, kindly help.

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jixian.yang · 2010-10-30 12:39

The code for form, it is easy to be panel:

unit Unit1;

{$mode objfpc}{$H+}

interface

uses
  Classes, SysUtils, FileUtil, Forms, Controls, Graphics, Dialogs;

type

  { TForm1 }

  TForm1 = class(TForm)
    procedure FormMouseDown(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
    procedure FormMouseMove(Sender: TObject; Shift: TShiftState; X, Y:
Integer);
    procedure FormMouseUp(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
  private
    { private declarations }
  public
    { public declarations }

  end;

var
  Form1: TForm1;
  oldx,oldy,isMove: integer;

implementation

{$R *.lfm}

{ TForm1 }

procedure TForm1.FormMouseMove(Sender: TObject; Shift: TShiftState; X,
  Y: Integer);
begin
  if isMove=1 then
  begin
    left:=left +x-oldx;
    top:=top +y-oldy;
  end;

end;

procedure TForm1.FormMouseDown(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  oldx:=x;
  oldy:=y;
  isMove:=1;
end;

procedure TForm1.FormMouseUp(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  isMove:=0;
end;

end.

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asdf · 2010-10-31 02:22

Dear jixian.yang

Your code moved the TForm, it did not move the TPanel.
I just need to move the TPanel in the TForm, not the TForm.
Could you help me please?

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w135n03 · 2010-10-31 04:00

try this, i fix some code from jixian.yang

unit Unit1;

{$mode objfpc}{$H+}

interface

uses
  Classes, SysUtils, FileUtil, LResources, Forms, Controls, Graphics,
Dialogs,
  ExtCtrls;

type

  { TForm1 }

  TForm1 = class(TForm)
    Panel1: TPanel;
    procedure Panel1MouseDown(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
    procedure Panel1MouseMove(Sender: TObject; Shift: TShiftState; X,
Y: Integer
      );
    procedure Panel1MouseUp(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
  private
    { private declarations }
  public
    { public declarations }
  end;

var
  Form1: TForm1;
  oldX, oldY, isMove : Integer;

implementation

{ TForm1 }

procedure TForm1.Panel1MouseDown(Sender: TObject; Button:
TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  oldX := X;
  oldY := Y;
  isMove := 1;
end;

procedure TForm1.Panel1MouseMove(Sender: TObject; Shift: TShiftState;
X,
  Y: Integer);
begin
  if isMove = 1 then begin
    Panel1.Left := Panel1.Left + X - oldX;
    Panel1.Top := Panel1.Top + Y - oldY;
  end;
end;

procedure TForm1.Panel1MouseUp(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  isMove := 0;
end;

initialization
  {$I unit1.lrs}

end.

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asdf · 2010-10-31 05:29

One more feature please.
Is there any way to make it like "AlwayShowOnTop"?
Since it was sometimes hidden by some displaying controls.

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jixian.yang · 2010-10-31 12:15

If there must be a "AlwayShowOnTop" feature, we prefer TForm to
TPanel.

Here the Form1 worked as a "AlwayShowOnTop" TPanel:

program project1;

{$mode objfpc}{$H+}

uses
  {$IFDEF UNIX}{$IFDEF UseCThreads}
  cthreads,
  {$ENDIF}{$ENDIF}
  Interfaces, // this includes the LCL widgetset
  Controls, Forms, Unit1, Unit2
  { you can add units after this };

{$R *.res}

begin
  Application.Initialize;
  Application.CreateForm(TForm2, Form2);
  Application.CreateForm(TForm1, Form1);
  Form1.Parent := Form2;
  Form1.Top:=0;
  Form1.Left:=0;
  Form1.BorderStyle:=bsNone;
  Form1.FormStyle:=fsStayOnTop;
  Form1.Show;
  Application.Run;
end.

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asdf · 2010-10-31 14:15

Now the calculator can be moved/dragged perfect.

But if I click to show the calculator before showing the TPageControl,
the calculator was always hidden behind the TPageControl.

On the other hand, if I I click to show the calculator "after" showing
the TPageControl, the calculator was always on top of everything
(Sorry, I don't need to create another form).

Help me please.

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w135n03 · 2010-10-31 20:28

Code: [Select]unit Unit1;

{$mode objfpc}{$H+}

interface

uses
  Classes, SysUtils, FileUtil, LResources, Forms, Controls, Graphics,
Dialogs,
  ExtCtrls, ComCtrls, StdCtrls;

type

  { TForm1 }

  TForm1 = class(TForm)
    Button1: TButton;
    PageControl1: TPageControl;
    Panel1: TPanel;
    TabSheet1: TTabSheet;
    procedure Button1Click(Sender: TObject);
    procedure Panel1MouseDown(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
    procedure Panel1MouseMove(Sender: TObject; Shift: TShiftState; X,
Y: Integer
      );
    procedure Panel1MouseUp(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
  private
    { private declarations }
  public
    { public declarations }
  end;

var
  Form1: TForm1;
  oldX, oldY, isMove, isTop : Integer;

implementation

{ TForm1 }

procedure TForm1.Panel1MouseDown(Sender: TObject; Button:
TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  oldX := X;
  oldY := Y;
  isMove := 1;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  if isTop = 0 then begin
    Panel1.SendToBack;
    isTop := 1;
  end
  else if isTop = 1 then begin
    PageControl1.SendToBack;
    isTop := 0;
  end;
end;

procedure TForm1.Panel1MouseMove(Sender: TObject; Shift: TShiftState;
X,
  Y: Integer);
begin
  if isMove = 1 then begin
    Panel1.Left := Panel1.Left + X - oldX;
    Panel1.Top := Panel1.Top + Y - oldY;
  end;
end;

procedure TForm1.Panel1MouseUp(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  isMove := 0;
end;

initialization
  {$I unit1.lrs}

end.

I add some lines of code, may be it help. Sorry for my English

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arbelest · 2010-11-01 00:46

The code is OK, but i think it better if you create your own
components.
It will make your code more modular and reuseable.

About the code, you can modify w135n03's code like this
Code: [Select].....
procedure TForm1.Button1Click(Sender: TObject);
begin
    Panel1.visible=not Panel1.visible;
    if Panel1.visible then
       Panel1.BringToFront;
end;
...
It will make your calculator panel show on top when toggle visible.

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asdf · 2010-11-01 11:28

Quote from: arbelest on November 01, 2010, 01:46:58 am   
Panel1.visible=not Panel1.visible;

There is an error message against this line.
Error: Illegal Expression

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typo · 2010-11-01 11:37

You are missing the ':' before the '='.

Code: [Select]Panel1.visible := not Panel1.visible;

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asdf · 2010-11-01 12:53

The result is the same ...

If I click to show the calculator before showing the TPageControl, the
calculator was always hidden behind the TPageControl. Why the
calculator could not brought'ToFront?

On the other hand, if I I click to show the calculator "after" showing
the TPageControl, the calculator was always on top of everything. Very
strange!

I tried to use the code posted by: w135n03
(and I created a procedure to hide the TPageControl ......

Procedure TMajorForm_Form.SendToBackTPageControl;
  begin
  for i := 0 to MajorForm_Form.ControlCount - 1 do
  if MajorForm_Form.Controls is TPageControl then
  //MajorForm_Form.Controls.Visible:= false;
  MajorForm_Form.Controls.SendToBack;
end;                                  

But still not perfect, I'm afraid that ...
MajorForm_Form.Controls.SendToBack;
is still wrong.

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arbelest · 2010-11-02 01:09

Quote from: asdf on November 01, 2010, 01:53:32 pmOn the other hand,
if I I click to show the calculator "after" showing the TPageControl,
the calculator was always on top of everything. Very strange!

Sorry i confuse about "always on top of everything". Did you mean
overlap all other panel, including top panel contain toggle button etc
? What is calculator's control parent ? If it is Main Form, of course
it will overlap all other control inside main form.
Assuming it's OK if calculator always on top of everything and
PageControl is toggle too, you can try :
Code: [Select]...
procedure TMainForm.ButtonToggleCalculatorClick(Sender: TObject);
begin
    PanelCalculator.visible:=not PanelCalculator.visible;
    if PanelCalculator.visible then
       PanelCalculator.BringToFront;
end;
...
procedure TMainForm.ButtonTogglePageControlClick(Sender: TObject);
begin
   PageControl1.visible:=not PageControl1.visible
   // force bring calculator to front if it visible
   if PanelCalculator.visible then
      PanelCalculator.BringToFront;
end;
...

@typo: thanks for your correction

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asdf · 2010-11-03 03:38

Everything is in only one form.
When a TPageControl shows, it will fit the width and  height of Form
except TMenu and TToolbar.

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asdf · 2010-11-08 07:37

Quote from: typo on November 01, 2010, 12:37:39 pmCode:
[Select]Panel1.visible := not Panel1.visible;
Could anybody explain the meaning of this syntax please?

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Mando · 2010-11-08 07:46

Hello:

This code toggles the visibility of Panel1.
If Panel1 is visible, the code hides it. If It's hidden,  making it
visible.


Regards

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asdf · 2010-11-08 08:00

Thank you so much