IWAppFormAsyncResize fired without reason

[Lenfors]

Hello!

Discovered another strange ting in IntraWeb 15.2.69.

Try the following:

Create a new IW application and put a TIWTabControl on it.
Add a couple of pages to the TabControl.
Create an event for the forms OnAsynchResize.

When running the application the OnAsynchResize is fired once as it should and you can switch between the pages on the TabControl and no more OnAsynchResize is fired.

Now add an event to the TabControls OnChange event, it can be an empty event doing nothing.

Now when you run the program the OnAsynchResize event is fired on program startup as it should, but it's also fired every time you change page in the page control!

This is a big issue for me as I use the OnAsynchResize event for rescaling every component on the form.

Am i missing soething here? Is this normal behaviour?

Best regards, Mikael


object IWForm2: TIWForm2
  Left = 0

  Top = 0

  Width = 555

  Height = 400

  RenderInvisibleControls = True

  AllowPageAccess = True

  ConnectionMode = cmAny

  OnAsyncResize = IWAppFormAsyncResize

  Background.Fixed = False

  HandleTabs = False

  LeftToRight = True

  LockUntilLoaded = True

  LockOnSubmit = True

  ShowHint = True

  DesignLeft = 3

  DesignTop = 3

  object IWTabControl1: TIWTabControl

    Left = 96

    Top = 72

    Width = 305

    Height = 225

    RenderInvisibleControls = True

    OnChange = IWTabControl1Change

    ActiveTabFont.Color = clWebWHITE

    ActiveTabFont.FontFamily = 'Arial, Sans-Serif, Verdana'

    ActiveTabFont.Size = 10

    ActiveTabFont.Style = [fsBold]

    ActiveTabFont.PxSize = 13

    InactiveTabFont.Color = clWebBLACK

    InactiveTabFont.FontFamily = 'Arial, Sans-Serif, Verdana'

    InactiveTabFont.Size = 10

    InactiveTabFont.Style = []

    InactiveTabFont.PxSize = 13

    ActiveTabColor = clWebDARKGRAY

    InactiveTabColor = clWebLIGHTGRAY

    ActivePage = 0

    BorderOptions.NumericWidth = 0

    BorderOptions.Style = cbsNone

    Color = clWebSILVER

    ClipRegion = False

    TabPadding = 0

    ActiveTabBorder.Color = clWebBLACK

    ActiveTabBorder.Width = 0

    InactiveTabBorder.Color = clWebBLACK

    InactiveTabBorder.Width = 0

    DesignSize = (

      305

      225)

    object IWTabControl1Page0: TIWTabPage

      Left = 0

      Top = 20

      Width = 305

      Height = 205

      RenderInvisibleControls = True

      Title = 'Page0'

      BorderOptions.NumericWidth = 0

      BorderOptions.Style = cbsNone

      Color = clWebWHITE

    end

    object IWTabControl1Page1: TIWTabPage

      Left = 0

      Top = 20

      Width = 305

      Height = 205

      RenderInvisibleControls = True

      TabOrder = 1

      Title = 'Page1'

      BorderOptions.NumericWidth = 0

      BorderOptions.Style = cbsNone

      Color = clWebWHITE

    end

  end
end



unit Unit2;
interface

uses

  Classes, SysUtils, IWAppForm, IWApplication, IWColor, IWTypes,

  IWCompTabControl, Vcl.Controls, Vcl.Forms, IWVCLBaseContainer, IWContainer,

  IWHTMLContainer, IWHTML40Container, IWRegion;

type

  TIWForm2 = class(TIWAppForm)

    IWTabControl1: TIWTabControl;

    IWTabControl1Page0: TIWTabPage;

    IWTabControl1Page1: TIWTabPage;

    procedure IWAppFormAsyncResize(Sender: TObject; EventParams: TStringList);

    procedure IWTabControl1Change(Sender: TObject);

  public

  end;

implementation

{$R *.dfm}



procedure TIWForm2.IWAppFormAsyncResize(Sender: TObject; EventParams: TStringList);

begin

// Put breakpoint here if you want to see when it's fired

end;



// If this function is removed everything works fine!

procedure TIWForm2.IWTabControl1Change(Sender: TObject);   

begin

//

end;



initialization

  TIWForm2.SetAsMainForm;


end.

[Alexandre Machado]

The OnChange event of the PageControl triggers a full postback and the page is re-rendered, which means that it will trigger a new OnAsyncResize event (which happens every time a page is rendered). This is normal an expected.

I would suggest for you to try the new IWjQPageControl instead of the IWTabControl component, however it doesn't contain an AsyncChange event. It's in our todo list but not ready yet.

[Lenfors]

Hello!

Ok, thanks. Then I think the OnAsynchResize has a very strange name :-) OnRenderComplete would have been much better.
When starting with IntraWeb this sort of proplems take ages to figure out. Is there some kind of documentation where all these behaviours are documented?

I tried the IWjQPageControl but it's missing the Align property!?
I also tried to create a page in the IWjQPageControl and put a IWRegion aligned to client in it. The problem now is that when the IWjQPageControl the IWRegion does not update it's size correctly!?

Best regards, Mikael