Solved

Hide a property

Posted on 2004-10-07
7
218 Views
Last Modified: 2010-05-18
How can I hide one of my property ? I moved to public area, but in this case don't save my settings. Just when I let it into published my vcl save parameters to dfm file.

What to do to have it hidden but to store my parameters ?
0
Comment
Question by:ginsonic
  • 3
  • 2
  • 2
7 Comments
 
LVL 7

Expert Comment

by:LRHGuy
ID: 12251778
In your component, add:

private
   fYourPropertyBool:boolean;
protected
    procedure DefineProperties(Filer:TFiler);
      override;


Then make:

procedure Comp.DefineProperties(Filer:TFiler);
begin
  inherited DefineProperties(Filer); { allow base classes to define properties }
  Filer.DefineProperty('YourPropertyName'',True,LoadProperty_YourPropertyBoll,StoreProperty_YourPropertyBool,True);
end;

procedure Comp.LoadProperty_YourPropertyBool(Reader:TReader);
begin
  fYourPropertyBool:=Reader.ReadBoolean;
end;

procedure Comp.StoreProperty_YourPropertyBool(Writer:TWriter);
begin
  Writer.WriteBoolean(fYourPropertyBool);
end;


fYourPropertyBool just happens to be a boolean property. Make whatever you need!

0
 

Expert Comment

by:joncmora
ID: 12255496
I don't see the reason why you want to do this.

How can that property be assigned a value at design time when it's not published? IMO, the purpose of the DFM file is to store (non-default) values set at design time. Other than that, you have to assign your values in code.
0
 
LVL 7

Expert Comment

by:LRHGuy
ID: 12255512
I sometimes do this to store a state variable related to but not directly addressable by a user definable property. For example, if it's using an internally generated bitmap, or one the user supplied.
0
Active Directory Webinar

We all know we need to protect and secure our privileges, but where to start? Join Experts Exchange and ManageEngine on Tuesday, April 11, 2017 10:00 AM PDT to learn how to track and secure privileged users in Active Directory.

 

Expert Comment

by:joncmora
ID: 12255529
I see. Now I think I know what ginsonic is trying to achieve.
0
 
LVL 9

Author Comment

by:ginsonic
ID: 12256011
My property is a TCollection not a boolean. What to do ?

I wish to hide it because I use my own editor when double click on vcl.
0
 
LVL 7

Accepted Solution

by:
LRHGuy earned 500 total points
ID: 12263672
It's the same setup, you'll just have to save the collection, item by item, in the save routine (and the load routine)

procedure Comp.LoadProperty_YourProperty(Reader:TReader);
begin
// load your collection here
  Reader.ReadCollection(MyCollection);
end;

procedure Comp.StoreProperty_YourProperty(Writer:TWriter);
begin
// save your collection here
  Writer.WriteCollection(MyCollection);
end;

The ReadCollection and WriteCollection will call Read/WriteProperties() for each item in the list.

Note that you'll have to have each of the individual fields of the collection items defined as property in the DefineProperties method.
0
 
LVL 9

Author Comment

by:ginsonic
ID: 12265268
LRHGuy, I use same code untill now. For defineProperties I use:

procedure TmyVcl.DefineProperties(Filer: TFiler);
begin
  inherited DefineProperties(Filer);
  Filer.DefineProperty('MyCollection', LoadProperty, StoreProperty, FMyCollection.Count > 0);
end;

Can you tell me more, maybe codes, for defining the fields of  my  collection?
0

Featured Post

Free Tool: Path Explorer

An intuitive utility to help find the CSS path to UI elements on a webpage. These paths are used frequently in a variety of front-end development and QA automation tasks.

One of a set of tools we're offering as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

The uses clause is one of those things that just tends to grow and grow. Most of the time this is in the main form, as it's from this form that all others are called. If you have a big application (including many forms), the uses clause in the in…
Introduction Raise your hands if you were as upset with FireMonkey as I was when I discovered that there was no TListview.  I use TListView in almost all of my applications I've written, and I was not going to compromise by resorting to TStringGrid…
Email security requires an ever evolving service that stays up to date with counter-evolving threats. The Email Laundry perform Research and Development to ensure their email security service evolves faster than cyber criminals. We apply our Threat…

820 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question