MenuItem Caption

[Zath]

How do I get a MenuItem caption and concatenate it to the main form title ?
Currently I have DefaultCaption and the actual item name as a string.
The menu item has the name itself and I was wondering if I can get that as a caption and have a generic line for all menu clicks.
Something like
Form1.Caption :=DefaultCaption+Sender.Caption.

Code: Pascal  [Select][+][-]

1. procedure TForm1.MenuItem21Click(Sender: TObject);
2. begin
3.   ItmNo:=2;
4.   Form1.Caption :=DefaultCaption+' : BigMap';
5.   MemoGeneral.Lines.LoadFromFile(drName+'\M2Server\Envir\BigMap.txt');
6. end;
7.  

[lucamar]

How about:

Code: Pascal  [Select][+][-]

1. Caption := DefaultCaption;
2. if Sender.InheritsFrom(TMenuItem) then
3.   Caption := Caption + (Sender as TMenuItem).Caption;

or just

Code: Pascal  [Select][+][-]

1. Caption := DefaultCaption + (Sender as TMenuItem).Caption;

[Zath]

How about:

Code: Pascal  [Select][+][-]

1. Caption := DefaultCaption;
2. if Sender.InheritsFrom(TMenuItem) then
3.   Caption := Caption + (Sender as TMenuItem).Caption;

or just

Code: Pascal  [Select][+][-]

1. Caption := DefaultCaption + (Sender as TMenuItem).Caption;

Thanks lucamar, both look like options. My lack of familiarity with some of the object methods clearly needs improving.

[Zath]

I created a small procedure for your first example and it works fine.
The second option works fine too but gives me less saving in code.

Thanks again.

[lucamar]

Glad to be of help!

[furious programming]

The TMenuItem.OnClick event always provides in the parameter an instance of the TMenuItem class, so checking the parameter type is not needed. Of course unless someone calls the event from the code level and gives the object another of class, but this should not be done, because TMenuItem has the Click method.

So you can confidently treat the parameter as TMenuItem:

Code: Pascal  [Select][+][-]

1. procedure TForm.MenuItemClick(ASender: TObject);
2. var
3.   MenuItem: TMenuItem absolute ASender;
4. begin
5.   Caption := DefaultCaption + MenuItem.Caption;
6. end;

[lucamar]

The TMenuItem.OnClick event always provides in the parameter an instance of the TMenuItem class, so checking the parameter type is not needed. Of course unless someone calls the event from the code level and gives the object another of class, but this should not be done, because TMenuItem has the Click method.

You're right, of course; in fact that's what I do always: just call AMenuItem.Click if needed--same with the other classes that have a Click method, like TButton.

It's just that, after having been burned quite a few times, now I always check Sender against the needed class. Beter safe than sorry, I always say

The one thing I don't like about your proposal is the unneccessary use of absolute. It's maybe a knee-jerk reaction nut since soft-casting with as is readily available, I wouldn't use it. If anything, to avoid extra typing if Sender is referenced many times, I would just do:

Code: Pascal  [Select][+][-]

1. procedure TForm.MenuItemClick(ASender: TObject);
2. var
3.   AMenuItem: TMenuItem;
4. begin
5.   AMenuItem := Sender as TMenuItem;
6.   Caption := DefaultCaption + AMenuItem.Caption;
7.   {... etc ...}
8. end;

RE . setting the form's caption, maybe it would be better to generalize the process with something like:

Code: Pascal  [Select][+][-]

1. TForm1.BuildCaption(AnObject: TObject): String;
2. begin
3.   Result := DefaultCaption;
4.   if Assigned(AnObject) then begin
5.     if AnObject.InheritsFrom(TControl) then
6.       Result := Result + (AnObject as TControl).Caption
7.     else if AnObject.InheritsFrom(TMenuItem) then
8.       Result := Result + (AnObject as TMenuItem).Caption;
9.     { add other components with Caption which don't inherit from TControl }
10.   end;
11. end;

[Zath]

Interesting ideas that I can try.
Thanks !