TFrame crash with specific components.
lazarus / 31-LCL

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dariov · 2014-07-17 17:04

Hello community:
I have detected a possible bug in the frames of Lazarus (1.0, 1.2.2,
1.3trunk) when it used with custom components. The problem manifests
itself when the custom component is embedded in frame and then the
frame is add to a form then try to run the program, which throws an
exception (The Control'' has no parent window) some time in design
time and some time in run time (depending of the component)...
To see the problem please install the customdrawn package that comes
with lazarus, create a frame insert one CDPageControl create
CDTabSheet a page or two and then try to insert the frame within a
form.
This is a bug of my custom components and the CDPageControl or more
serious and general bug?....
IMPORTANT "Out of the frames the custom components work perfectly "
Best Regards

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howardpc · 2014-07-17 22:13

It seems to be a bug not so much with frames as such, but with how
frame data is stored in the .lfm when the frame contains tabsheets of
a TCDPageControl.

A TCDPageControl containing at least one TCDTabsheet seems not to get
its tabsheet property data stored correctly  if it is contained in a
frame nested in another container. (Tabsheets of a regular
TPageControl inside a frame are stored OK). In some cases the lfm data
refers to tabsheets by index (e.g. tabsheet[0]) rather than by
component name. The "[" and "]" are of course illegal Pascal
characters in identifier names.

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dariov · 2014-07-18 13:19

I do not see the problem of malformed names in lfm file, but I use
indexes on the properties of my components, I will try without
them....

++++  Fragment the definition of the TElevation Type  +++++
    property Color_Back: TColor    index 0 read GetColor write
SetColor default clTeal;
    property Color_Ray: TColor     index 1 read GetColor write
SetColor default clLime;
    property Color_Mark: TColor    index 2 read GetColor write
SetColor default clRed;
    property Color_Rect: TColor    index 3 read GetColor write
SetColor default clWhite;
------   Fragment the definition of the TElevation Type  -------

+++  frame1 lfm file +++
object Frame1: TFrame1
  Left = 0
  Height = 240
  Top = 0
  Width = 320
  ClientHeight = 240
  ClientWidth = 320
  TabOrder = 0
  DesignLeft = 719
  DesignTop = 131
  object Elevation1: TElevation
    Left = 0
    Height = 240
    Top = 0
    Width = 320
    AntennaType = at_Elevation
    Count_Small = 144
    Align = alClient
  end
end
---  frame1 lfm file ---

+++ form1 lfm file +++
object Form1: TForm1
  Left = 272
  Height = 240
  Top = 174
  Width = 320
  Caption = 'Form1'
  ClientHeight = 240
  ClientWidth = 320
  LCLVersion = '1.2.2.0'
  inline Frame1_1: TFrame1
    Align = alClient
  end
end
--- form1 lfm file ---

Note: In the component implementation i call inherited method of all
override methods and the component works fine direct on a frame...

Best Regards