How to show or hide the mouse

[witenite]

Hi,
I recently converted a program I have written using Delphi into Lazarus. My program has the following command in its code:

ShowCursor(False);  // Hide cursor (Mouse) when we hover anywhere over the form

This however cannot compile (Lazarus does not know what showcursor is). Basically this is a method for hiding the mouse whenever the mouse is over my form (I don't want to see the mouse cursor, and this works perfectly in Delphi). I have looked online for help, but the best I could find was a very old reference here:

http://forum.lazarus.freepascal.org/index.php?topic=11655.0

Apparently showcursor used to work many years ago, but no longer does (or at least that is the best interpretation I can get from the forums. Am I missing a USE file or link, or does Lazarus have some other means of hiding the cursor?

[balazsszekely]

I suppose you're under windows. If yes, just add JwaWindows to the uses clauses and you're good to go.

Code: Pascal  [Select][+][-]

1. uses JwaWindows;
2.  
3. procedure TForm1.FormMouseEnter(Sender: TObject);
4. begin
5.   ShowCursor(False);
6. end;
7.  
8. procedure TForm1.FormMouseLeave(Sender: TObject);
9. begin
10.   ShowCursor(True);
11. end;
12.  

[rvk]

I suppose you're under windows. If yes, just add JwaWindows to the uses clauses and you're good to go.

Uh... doesn't the Windows-unit have the same ShowCursor() defined? 
(at least trunk does)

Code: Pascal  [Select][+][-]

1. uses Windows;

[balazsszekely]

@rvk
Uh... doesn't the Windows-unit have the same ShowCursor() defined?

Yes it does, but I like jwaWindows better, it's seem to me that it has a more complete api declarations. 

[Zath]

@rvk
Uh... doesn't the Windows-unit have the same ShowCursor() defined?

Yes it does, but I like jwaWindows better, it's seem to me that it has a more complete api declarations. 

So does this mean there are duplicate options within the default Lazarus installation ?

[balazsszekely]

@Zath
So does this mean there are duplicate options within the default Lazarus installation ?

Although are some overlapping api declarations, I wouldn't call it "duplicate". The windows unit is similar to delphi's windows unit, jwaWindows on the other hand is the port of the JEDI API library & security code library.

[RWC]

How about: Form1.Cursor := crNone; //in LCL/controls.pp?

[JuhaManninen]

How about: Form1.Cursor := crNone; //in LCL/controls.pp?

Yes, that is the cross-platform solution.
Please remember that Lazarus is a cross-platform system and lots of effort was made to implement it.
The Windows unit or similar should not be used, unless you are really creating a Windows specific program!

[balazsszekely]

Ok, but the OP explicitly asked about ShowCursor api.

[witenite]

I suppose you're under windows. If yes, just add JwaWindows to the uses clauses and you're good to go.

Code: Pascal  [Select][+][-]

1. uses JwaWindows;
2.  
3. procedure TForm1.FormMouseEnter(Sender: TObject);
4. begin
5.   ShowCursor(False);
6. end;
7.  
8. procedure TForm1.FormMouseLeave(Sender: TObject);
9. begin
10.   ShowCursor(True);
11. end;
12.  

[witenite]

I suppose you're under windows. If yes, just add JwaWindows to the uses clauses and you're good to go.

Code: Pascal  [Select][+][-]

1. uses JwaWindows;
2.  
3. procedure TForm1.FormMouseEnter(Sender: TObject);
4. begin
5.   ShowCursor(False);
6. end;
7.  
8. procedure TForm1.FormMouseLeave(Sender: TObject);
9. begin
10.   ShowCursor(True);
11. end;
12.  

Actually I'm using Lazarus on my home computer, which is Linux (Ubuntu) based. The Delphi package I use at work though, which is Windows based, hence the reason for using Showcursor.

[witenite]

How about: Form1.Cursor := crNone; //in LCL/controls.pp?

Thanks! based on what I have read down below, this is a cross platform option, which will work quite nicely for me, as I am not using Windows at home, but instead run Ubuntu Linux. Thanks for all your help (and to the other people providing useful comments here too).

[Sergei]

Code: Pascal  [Select][+][-]

1. Screen.Cursor := crNone

[rvk]

Code: Pascal  [Select][+][-]

1. Screen.Cursor := crNone

Note that Screen.Cursor := crNone doesn't completely eliminate the mouse-pointer.
When you hover over a border of an edit, the mouse-pointer is visible again (and invisible again if you move off the border).

ShowCursor(False) does not have that problem (but might be a Windows-only solution).