TFont property on descesndant of TfrxMemoView

Comments

• Richard17

  April 2017 edited 9:43PM

  For those that may be interested, I am answering my QUESTION #2:
  
  Solved by registering my extended property as such (in initialization section)
  
  frxPropertyEditors.Register(TypeInfo(Extended), TfrxComponent, 'MyExtendedPropName', TfrxLocSizeXProperty);
  
  Anyone can help with my QUESTION #1?
  
  Richard
  
  

  Richard17 wrote: »

  We have created a descendant of the TfrxMemoView class.
  
  In this descendant, we added a TPersistent property
  
  TMgrGroupStyle = class(TPersistent)
  private
  FFrame: TFrxFrame;
  FUseFrame: Boolean;
  FFont: TFont;
  FUseFont: Boolean;
  public
  procedure Assign(Source: TPersistent); override;
  constructor Create; overload;
  destructor Destroy; override;
  
  published
  property UseFont: Boolean read FUseFont write FUseFont;
  property UseFrame: Boolean read FUseFrame write FUseFrame;
  property Font: TFont read FFont write FFont;
  property Frame: TFrxFrame read FFrame write FFrame;
  end;
  
  TMgrIndentMemoView = class(TfrxMemoView)
  private
  ...
  FGroupStyle: TMgrGroupStyle;
  
  public
  constructor Create(AOwner: TComponent); override;
  destructor Destroy; override;
  
  class function GetDescription: String; override;
  
  procedure Draw(Canvas: TCanvas; ScaleX, ScaleY, OffsetX, OffsetY: Extended); override;
  function Diff(AComponent: TfrxComponent): string; override;
  
  published
  ...
  property GroupStyle: TMgrGroupStyle read FGroupStyle write FGroupStyle;
  
  procedure GetData; override;
  end;
  
  
  My new GroupStyle property is displayed in the object inspector and I can use it to trigger some special code in my overriden Draw event, so far so good. It works if I change one of the GroupStyle.Font property directly in the object inspector, but creates an AV when I try to use the font dialog via the button (besides font property).
  
  What am I missing so to get rid of the AV.
  
  AV seems to be triggered here:
  
  procedure TfrxXMLSerializer.WriteRootComponent(Root: TfrxComponent;
  SaveChildren: Boolean = True; XMLItem: TfrxXMLItem = nil; Streaming: Boolean = False);
  var
  XMLDoc: TfrxXMLDocument;
  
  procedure DoWrite(Item: TfrxXMLItem; ARoot: TfrxComponent);
  var
  i: Integer;
  begin
  if ARoot.IsAncestor and not Streaming then
  Item.Name := 'inherited'
  else
  Item.Name := ARoot.ClassName;
  if ARoot = Root then
  Item.Text := ObjToXML(ARoot)
  else
  Item.Text := 'Name="' + ARoot.Name + '"' + ObjToXML(ARoot); //<-- On this line
  if FHandleNestedProperties and (csHandlesNestedProperties in ARoot.frComponentStyle) then
  ARoot.WriteNestedProperties(Item);
  if SaveChildren then
  for i := 0 to ARoot.Objects.Count - 1 do
  DoWrite(Item.Add, ARoot.Objects);
  end;
  
  
  Do I need to declare my property differently so ObjToXML can digest it better?
  
  I tried adding the following line in the initialization, but that didn't fix it:
  
  Initialization
  frxPropertyEditors.Register(TypeInfo(TFont), TMgrIndentMemoView, 'HeaderGroupStyle.Font', TfrxFontProperty);
  
  QUESTION #2
  Also, my descendant has an extended property that I would like to treat like all the other properties that get affected by a units type change (when the user double clicks on the status bar of the object inspector to toggle between inches, centimeters, pixels, etc..) Can't find where that gets done. Can you point me in the right direction?
  
  Please and thank you,
  Richard
• Richard17

  April 2017 edited 9:43PM

  Also answering my QUESTION #1: (for those interested)
  
  I needed to include an Assign method.
  
  procedure TMyPersistent.Assign(Source: TPersistent);
  var
  P: TMyPersistent;
  
  begin
  if Source is TMyPersistent then
  begin
  P := (Source as TMyPersistent);
  
  //assign copy stuff here
  end
  else
  inherited;
  end;
  
  Richard
• Richard17

  April 2017 edited 9:43PM

  Correction, that didn't fix it. I still need help with this.
  
  

  Richard17 wrote: »

  Also answering my QUESTION #1: (for those interested)
  
  I needed to include an Assign method.
  
  procedure TMyPersistent.Assign(Source: TPersistent);
  var
  P: TMyPersistent;
  
  begin
  if Source is TMyPersistent then
  begin
  P := (Source as TMyPersistent);
  
  //assign copy stuff here
  end
  else
  inherited;
  end;
  
  Richard
• Richard17

  April 2017 edited 9:43PM

  Now fixed. What really fixed it is defining a setter for my Font property which would Assign the Font.
  
  Somehow I feel like nobody is monitoring this forum [img]style_emoticons/<#EMO_DIR#>/dry.gif" style="vertical-align:middle" emoid="<_<" border="0" alt="dry.gif" /> Richard[/img]

  Richard17 wrote: »

  Correction, that didn't fix it. I still need help with this.
  
  

  Richard17 wrote: »

  Also answering my QUESTION #1: (for those interested)
  
  I needed to include an Assign method.
  
  procedure TMyPersistent.Assign(Source: TPersistent);
  var
  P: TMyPersistent;
  
  begin
  if Source is TMyPersistent then
  begin
  P := (Source as TMyPersistent);
  
  //assign copy stuff here
  end
  else
  inherited;
  end;
  
  Richard