How to block all incoming message to a form while thread is executing

问题

i have the current scenario, im using omnithreadlibrary for some generic background work like this:

TMethod = procedure of object;

TThreadExecuter = class;

IPresentationAnimation = interface
  ['{57DB6925-5A8B-4B2B-9CDD-0D45AA645592}']
  procedure IsBusy();
  procedure IsAvaliable();
end;

procedure TThreadExecuter.Execute(AMethod: TMethod); overload;
var ATask : IOmniTaskControl;
begin
  ATask := CreateTask(
    procedure(const ATask : IOmniTask) begin AMethod(); end
  ).OnTerminated(
    procedure begin ATask := nil; end
  ).Unobserved().Run();

  while Assigned(ATask) do
    begin
      Sleep(10);
      Application.ProcessMessages;
    end;
end;

procedure TThreadExecuter.Execute(ASender: TCustomForm; AMethod: TMethod); overload;
var AAnimator : IPresentationAnimation;
begin
  if(Assigned(ASender)) then
    begin
      TInterfaceConsolidation.Implements(ASender, IPresentationAnimation, AAnimator, False);
      if(Assigned(AAnimator)) then AAnimator.IsBusy()
      else ASender.Enabled := False;
    end;
  try
    Self.Execute(AMethod);
  finally
    if(Assigned(ASender)) then
      begin
        if(Assigned(AAnimator)) then AAnimator.IsAvaliable()
        else ASender.Enabled := True;
      end;
  end;
end;

so before i start executing i block the interface like this:

TMyForm = class(TForm, IPresentationAnimation);

procedure TMyForm.LoadData();
begin
  TThreadExecuter.Execute(Self, Self.List);
end;

procedure TMyForm.IsBusy();
begin
  try
    Self.FWorker := TPresentationFormWorker.Create(Self);
    Self.FWorker.Parent := Self;
    Self.FWorker.Show();
  finally
    Self.Enabled := False;
  end;
end;

and when the thread finish i release the block like this:

procedure TMyForm.IsAvaliable();
begin
  try
    Self.FWorker.Release();
  finally
    Self.Enabled := True;
  end;
end;

note: TPresentationFormWorker is a animated form that i put in form of the busy one.

the problem is that when the form is "busy" executing the thread even after i disable it, i can still interact with him, for example:

i can click in any button and when the thread finish the execution the action of the button are triggered;
i can typing in any control, e.g a Edit some nonsense information and when the thread finish the execution the content i provided to the control are erased back to before (ui rollback? lol);

so my guess is that while the thread are working thanks to the application.processmessages the interaction i made to the disable form are sended to the queue and once the thread finish they are all send back to the form.

my question is: is possible to actually disable the form, when i say disable i mean block all messages until certain point that i manually allow that can start accept again?

thx in advance.

来源：https://stackoverflow.com/questions/28372900/how-to-block-all-incoming-message-to-a-form-while-thread-is-executing

标签

Delphi

delphi-xe2

omnithreadlibrary