[SOLVED] Align objects at runtime

[tudi_x]

sorry. the label still does not move on the right side of the form.
to anchor top (AnchorSideTop.Control := self;) and left (AnchorSideLeft.Control := self;) it works.
but not to anchor on right.

what is the effect of AnchorSideRight? how is it used?

[taazz]

how come it works for the left side?

as I said use the property anchors never said anything about command.

Code: Pascal  [Select][+][-]

1. procedure TForm1.FormCreate(Sender: TObject);
2. var
3.   l: TLabel;
4. begin
5.   l := TLabel.Create(self);
6.   l.Parent := self;
7.   l.Caption := 'this is a test';
8.   l.Visible := True;
9.   l.Top := 50;
10.   l.Color := clYellow;
11.   l.Left := self.Width - l.Width - 4;
12.   l.Anchors:=[akRight, akTop];//sticks to the top right side.
13.   //l.Anchors:=[akRight, akbottom];
14.   Form1.Caption := IntToStr(self.Width) + '|' + IntToStr(l.Width) + '|' + IntToStr(l.Left);
15. end;
16.  

this should stick the label on its parent top, right side ee it will move elative to the top and right sides of the parent add an akbottom to make the label resize its height as the parent size changes. keep in mind that the property anchors is a set not a simple value.

[howardpc]

To do this by anchoring alone (i. e. not manually calculating and setting a value for Left) you have to write this (setting two properties of AnchorSideRight):

Code: Pascal  [Select][+][-]

1. procedure TForm1.FormCreate(Sender: TObject);
2. var
3.   l: TLabel;
4. begin
5.   l := TLabel.Create(self);
6.   l.Caption := 'xxxx';
7.   l.Top := 50;
8.   l.Color := clYellow;
9.   l.AutoSize := False;
10.   l.Anchors := [akRight];
11.   l.AnchorSideRight.Control := Self;
12.   l.AnchorSideRight.Side := asrRight;
13.   l.Parent := Self;
14.   Form1.Caption := IntToStr(self.Width) + '|' + IntToStr(l.Width) + '|' + IntToStr(l.Left);
15. end;

You'll note that anchoring works by 'sticking' controls to other controls, not by setting Top, Left values.
Top is set in this code (the label's top side is not anchored).
Left is not set in this code, either by the programmer, or by the anchoring code. Hence the form Caption shows the value of Left unaltered from 0 (the value all integers are initialised to when the class is created), even though the control is placed well away from the Left of the form.
BTW, it is better to set the Parent property last. This avoids  various assignments cascading unnecessarily with every property change made after Parent is set.

[tudi_x]

thank you!
i have managed now to align and arrange my TLabels in the TPanel:

Code: Pascal  [Select][+][-]

1. P: TPanel;
2.  
3. procedure TForm1.FormCreate(Sender: TObject);
4. var
5.   l1: TLabel;  //top
6.   l2: TLabel;  //middle
7.   l3: TLabel;  //bottom
8.  
9. begin
10.   l1 := TLabel.Create(P);
11.   l1.Caption := 'top';
12.   l1.Color := clYellow;
13.   l1.AutoSize := False;
14.   l1.Anchors := [akRight, akTop];
15.   l1.AnchorSideRight.Control := P;
16.   l1.AnchorSideRight.Side := asrRight;
17.   l1.AnchorSideTop.Control := P;
18.   l1.Alignment := taRightJustify;
19.   l1.Parent := P;
20.  
21.   l2 := TLabel.Create(P);
22.   l2.Caption := 'middle';
23.   l2.Color := clWhite;
24.   l2.AutoSize := False;
25.   l2.Anchors := [akRight, akTop];
26.   l2.AnchorSideRight.Control := P;
27.   l2.AnchorSideRight.Side := asrRight;
28.   l2.AnchorSideTop.Control := l1;
29.   l2.AnchorSideTop.Side := asrBottom;
30.   l2.BorderSpacing.Right:= 5;
31.   l2.Alignment := taRightJustify;
32.   l2.Parent := P;
33.  
34.   l3 := TLabel.Create(P);
35.   l3.Caption := 'bottom';
36.   l3.Color := clYellow;
37.   l3.AutoSize := False;
38.   l3.Anchors := [akRight, akTop];
39.   l3.AnchorSideRight.Control := P;
40.   l3.AnchorSideRight.Side := asrRight;
41.   l3.AnchorSideTop.Control := l2;
42.   l3.AnchorSideTop.Side := asrBottom;
43.   l3.Alignment := taRightJustify;
44.   l3.Parent := P;
45.  
46.   P.Height := l1.Height + l2.Height + l3.Height + 3;
47. end;  

[tudi_x]

is it possible to anchor an object that is not created at runtime to an object created at runtime?

is it possible to anchor an object that is created at runtime in one class - let us say a modified TLabel to another object created at runtime in another class (classes in different units)?
how would i pass the anchor reference as the names are not valid at design time?

[howardpc]

is it possible to anchor an object that is not created at runtime to an object created at runtime?

Of course. Drop a button and label on a new Lazarus project's main form. Complete the button OnClick event handler as follows:

Code: Pascal  [Select][+][-]

1. unit Unit1;
2.  
3. {$mode objfpc}{$H+}
4.  
5. interface
6.  
7. uses
8.   SysUtils, Forms, Controls, StdCtrls;
9.  
10. type
11.  
12.   TForm1 = class(TForm)
13.     CreateRuntimeLabelButton: TButton;
14.     DesignTimeLabel: TLabel;
15.     procedure CreateRuntimeLabelButtonClick(Sender: TObject);
16.   private
17.     FRuntimeLabel: TLabel;
18.   end;
19.  
20. var
21.   Form1: TForm1;
22.  
23. implementation
24.  
25. {$R *.lfm}
26.  
27. procedure TForm1.CreateRuntimeLabelButtonClick(Sender: TObject);
28. begin
29.   FRuntimeLabel:=TLabel.Create(Self);
30.   with FRuntimeLabel do begin
31.     Caption:='Runtime label';
32.     BorderSpacing.Around:=50;
33.     AnchorSideLeft.Control:=Self;
34.     AnchorSideTop.Control:=Self;
35.     Parent:=Self;
36.   end;
37.   with DesignTimeLabel do begin
38.     AnchorSideTop.Control:=FRuntimeLabel;
39.     AnchorSideTop.Side:=asrCenter;
40.     AnchorSideLeft.Control:=FRuntimeLabel;
41.     AnchorSideLeft.Side:=asrRight;
42.   end;
43. end;
44.  
45. end.

[tudi_x]

thank you Howard!

i made public an array of the objects that i create dynamically and now i can reference the first element of the array which i am sure would exist and have a horizontal coordinate.

[howardpc]

is it possible to anchor an object that is created at runtime in one class - let us say a modified TLabel to another object created at runtime in another class (classes in different units)?
how would i pass the anchor reference as the names are not valid at design time?

See the  little project attached.

[tudi_x]

thank you
i love Lazarus IDE