traping WM_RBUTTONDBLCLK message in a component

I think you have to subclass the owner.

GL
Mike

Application.HookMainWindow allows to get your private message feed.

hello EKIM, here's the code for a component that will do the right mouse button double click thing. It uses the Application.OnMessage to get the WM_RBUTTONDBLCLK. You should look into the Application.OnMessage if you are going to deal with windows messages. Oh, and in a component, it might be really UNwise to set the Handled to True, since it will knockout that message in ALL the forms of that app.

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unit RButDblClk;
interface
uses
  SysUtils, Windows, Messages, Classes, Forms;

type
  TOnRightDlbClick = procedure(Sender:TObject)of Object;
  TRButDblClk = class( TComponent )
  private
     FOnRightDlbClick: TOnRightDlbClick;
  protected
     procedure AppMessage(var Mesg: TMsg; var Handled: Boolean);
  public
     constructor Create( AOwner: TComponent ); override;
     destructor Destroy; override;
  published
     property OnRightDlbClick: TOnRightDlbClick read FOnRightDlbClick write FOnRightDlbClick;
  end;

procedure Register;

implementation

constructor TRButDblClk.Create( AOwner: TComponent );
begin
  inherited Create( AOwner );
  Application.OnMessage := AppMessage;
end;

destructor TRButDblClk.Destroy;
  begin
  inherited Destroy;
  end;

procedure TRButDblClk.AppMessage(var Mesg: TMsg; var Handled: Boolean);
begin
Handled := False;
if Mesg.message = WM_RBUTTONDBLCLK then
  begin
  if Assigned(FOnRightDlbClick) then FOnRightDlbClick(Self);
  end;
end;

procedure Register;
begin
  RegisterComponents('Additional', [TRButDblClk]);
end;

end.

Slick812, using Application.OnMessage in a component is unwise. Application.HookMainWindow is the way to go because it installs and handles a handler chain.

robert : With ApplicationHookMainWindow, what happen if the db right click occurs not on the main form, but on another application's form ? and if this form is not modal ?

regards

Mike

Nothing happens. Application.HookMainWindow is local to the application. It is like Application.OnMessage, only that a component should not occupy Application.OnMessage.

robert : ok, give me just some time to have a look on your solution.

Slick812 : thanks a lot for this full comment. Even it will maybe not the best solution, I do appreciate such comments.

regards

Mike

hi jacco !

Nice job ! It works fine, and I just had to copy/paste your example to be sure that it was what I need.

Points have been increased up to 150 for "really complete-full-working-answer".  :-)

Regards.

Mike