Changing DisplayNames of my properties using PropertyGrid component, how ??

Discussion in 'ASP .Net' started by Tugrul HELVACI, Dec 4, 2006.

  1. I'm using Delphi 2006 and I have a class defination like this:

    TPerson = class
    fPersonName : String;
    fPersonSurName : String;
    fPersonAge : Integer;
    published
    property PersonName : String read fPersonName write fPersonName;
    property PersonSurname : String read fPersonSurname write fPersonSurname;
    property PersonAge : Integer read fPersonAge write fPersonAge;
    end;

    and i want to display my class instance using PropertyGrid,so...

    var
    mPerson : TPerson;
    begin
    mPerson := TPerson.Create;
    mPerson.PersonName := 'Tugrul';
    mPerson.PersonSurname := 'HELVACI';
    mPerson.PersonAge := 31;
    PropertyGrid1.SelectedObject := mPerson;
    end;

    at the above code i can see my class instance in the property grid.
    But i want to change property display names in the propertygrid component.
    Because of these, i was searching on the net and i found PropertyDescriptor
    abstract class
    and ICustomTypeConverter interface.

    i implemented theese classes following:

    TArrayOfAttribute = array of Attribute;
    TMyDescriptor = class(PropertyDescriptor)
    private
    base : PropertyDescriptor;
    fName: String;

    function GetName : String;
    function GetDisplayName : String;
    function GetIsReadOnly : Boolean;
    function GetComponentType : &Type;
    function GetPropertyType : &Type;

    function GetCustomNames(baseName : String) : String; // my custom names
    getter function
    public
    constructor Create(baseP : PropertyDescriptor; filter :
    TArrayOfAttribute); overload; virtual;
    constructor Create(baseP : PropertyDescriptor); overload; virtual;

    function CanResetValue(comp : TObject) : Boolean;
    function GetValue(comp : TObject) : TObject;

    procedure ResetValue(comp : TObject);
    procedure SetValue(comp : TObject; Value : TObject);
    function ShouldSerializeValue(comp : TObject) : Boolean;


    property Name : String read GetName;
    property DisplayName : String read GetDisplayName;
    property IsReadOnly : Boolean read GetIsReadOnly;
    property ComponentType : &Type read GetComponentType;
    property PropertyType : &Type read GetPropertyType;
    end;

    TMyClass = class(TInterfacedObject, ICustomTypeDescriptor)
    public
    function GetProperties(filter : TArrayOfAttribute) :
    PropertyDescriptorCollection; overload;
    function GetAttributes : AttributeCollection;
    function GetClassName : String;
    function GetComponentName : String;
    function GetConverter : TypeConverter;
    function GetDefaultEvent : EventDescriptor;

    function GetEvents(attributes : TArrayOfAttribute) :
    EventDescriptorCollection; overload;
    function GetEvents : EventDescriptorCollection; overload;
    function GetDefaultProperty : PropertyDescriptor;

    function GetProperties : PropertyDescriptorCollection; overload;
    function GetEditor(editorBaseType : System.Type) : TObject;
    function GetPropertyOwner(pd : PropertyDescriptor) : TObject;
    end;


    and my new TPerson class is:
    TPerson = class(TMyClass)
    fPersonName : String;
    fPersonSurName : String;
    fPersonAge : Integer;
    published
    property PersonName : String read fPersonName write fPersonName;
    property PersonSurname : String read fPersonSurname write fPersonSurname;
    property PersonAge : Integer read fPersonAge write fPersonAge;
    end;

    **************** IMPLEMENTATIONS BELOW *********************************
    { TMyDescriptor }

    function TMyDescriptor.CanResetValue(comp: TObject): Boolean;
    begin
    Result := base.CanResetValue(comp);
    end;


    constructor TMyDescriptor.Create(baseP: PropertyDescriptor;
    filter: TArrayOfAttribute);
    begin
    inherited Create(baseP, filter);
    Self.base := baseP;
    end;

    constructor TMyDescriptor.Create(baseP: PropertyDescriptor);
    begin
    inherited Create(baseP);
    Self.base := baseP;
    end;

    function TMyDescriptor.GetComponentType: &Type;
    begin
    Result := base.ComponentType;
    end;

    function TMyDescriptor.GetDisplayName: String;
    begin
    Result := GetCustomNames(base.Name);
    end;

    function TMyDescriptor.Getir(baseName : String): String;
    begin
    if baseName = 'PersonName' then Result := 'Names of the Personel';
    if baseName = 'PersonSurname' then Result := 'Surname of the personel';
    if baseName = 'PersonAge' then Result := 'Age of the personel';
    end;

    function TMyDescriptor.GetIsReadOnly: Boolean;
    begin
    Result := base.IsReadOnly;
    end;

    function TMyDescriptor.GetName: String;
    begin
    Result := base.Name;
    end;


    function TMyDescriptor.GetPropertyType: &Type;
    begin
    Result := base.PropertyType;
    end;

    function TMyDescriptor.GetValue(comp: TObject): TObject;
    begin
    Result := base.GetValue(comp);
    end;


    procedure TMyDescriptor.ResetValue(comp: TObject);
    begin
    base.ResetValue(comp);
    end;

    procedure TMyDescriptor.SetValue(comp, Value: TObject);
    begin
    base.SetValue(comp, value);
    end;

    function TMyDescriptor.ShouldSerializeValue(comp: TObject): Boolean;
    begin
    Result := base.ShouldSerializeValue(comp);
    end;

    { TMyClass }

    function TMyClass.GetProperties(
    filter: TArrayOfAttribute): PropertyDescriptorCollection;
    var
    baseProps : PropertyDescriptorCollection;
    newProps : array of PropertyDescriptor;
    iCounter : Integer;
    oldname,
    newname : String;
    begin
    baseProps := TypeDescriptor.GetProperties(GetType(), filter);

    SetLength(newProps, baseProps.Count);

    for iCounter := 0 to baseProps.Count do
    begin
    newProps[iCounter] := TMyDescriptor.Create(baseProps[iCounter], filter);
    // An error occured : E2402 constructing instance of abstract class..
    oldname := PropertyDescriptor(baseProps[iCounter]).DisplayName;
    newName := TMyDescriptor(newProps[iCounter]).DisplayName;
    end;

    Result := PropertyDescriptorCollection.Create(newProps);
    end;

    function TMyClass.GetAttributes: AttributeCollection;
    begin
    Result := TypeDescriptor.GetAttributes(Self, true);
    end;

    function TMyClass.GetClassName: String;
    begin
    Result := TypeDescriptor.GetClassName(Self, true);
    end;

    function TMyClass.GetComponentName: String;
    begin
    Result := TypeDescriptor.GetComponentName(Self, true);
    end;

    function TMyClass.GetConverter: TypeConverter;
    begin
    Result := TypeDescriptor.GetConverter(Self, true);
    end;

    function TMyClass.GetDefaultEvent: EventDescriptor;
    begin
    Result := TypeDescriptor.GetDefaultEvent(Self, true);
    end;

    function TMyClass.GetDefaultProperty: PropertyDescriptor;
    begin
    Result := TypeDescriptor.GetDefaultProperty(Self, true);
    end;

    function TMyClass.GetEditor(editorBaseType: System.Type): TObject;
    begin
    Result := TypeDescriptor.GetEditor(Self, editorBaseType, true);
    end;

    function TMyClass.GetEvents: EventDescriptorCollection;
    begin
    Result := TypeDescriptor.GetEvents(Self, true);
    end;

    function TMyClass.GetEvents(
    attributes: TArrayOfAttribute): EventDescriptorCollection;
    begin
    Result := TypeDescriptor.GetEvents(Self, attributes, true);
    end;

    function TMyClass.GetProperties: PropertyDescriptorCollection;
    begin
    Result := TypeDescriptor.GetProperties(Self, true);
    end;

    function TMyClass.GetPropertyOwner(pd: PropertyDescriptor): TObject;
    begin
    Result := Self;
    end;


    I dont understand what is this. Can anybody helps me , how can i
    subclassing PropertyDescriptor class correctly ??


    Even we take an error when using delphi.net , we dont take any error
    message using c#,

    i want change the display name of the property which is the added to my
    special class by using the propertyGrid Component ...
    It's seems like DisplayNameAttirubute of the .net Framework 2.0

    With My Best Regards,

    Thanks For Helping
     
    Tugrul HELVACI, Dec 4, 2006
    #1
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  2. Tugrul HELVACI

    RobinS Guest

    I saw this posting in the following groups:

    microsoft.public.dotnet.faqs
    microsoft.public.dotnet.framework
    microsoft.public.dotnet.framework.interop
    microsoft.public.dotnet.framework.windowsforms
    microsoft.public.dotnet.framework.windowsforms.controls
    microsoft.public.dotnet.languages.csharp
    microsoft.public.dotnet.general

    When you post a message to multiple groups, please post all of
    them at once. That way, if someone in one group provides a
    solution, the solution will be posted to all of the groups.
    Also, if someone in another group is working on a solution,
    they will know it has been solved, and they can work on helping
    somebody else.

    Thanks,
    Robin S.
    ---------------------------------
     
    RobinS, Dec 4, 2006
    #2
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  3. DisplayNameAttribute found in System.ComponentModel

    Gabriel Lozano-Morán

     
    Gabriel Lozano-Morán, Dec 4, 2006
    #3
  4. DisplayNameAttribute is in .Net Framework 2.0 only not 1.1..
    Unfortunatelly Delphi 2006 supports 1.1

     
    Tuðrul HELVACI, Dec 5, 2006
    #4
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