[Lazarus] BoxRect

[Carlos German Tejero]

On Sat, 28 Mar 2009, Hans-Peter Diettrich wrote:

> Michael Van Canneyt schrieb:
> 
> > Is there a reason why ClipBoard.HasFormat() is so slow ?
> > 
> > Putting a call to ClipBoard.HasFormat() in an OnUpdate handler of an action
> > coupled to a toolbutton, seriously slows down an application, to the point
> > of being unusable. If I comment out the call, the application responds normally.
> 
> The request may go to the clipboard owner, which is responsible for 
> providing the clipboard contents in the various formats. The system also 
> may search for conversion tools, capable to render the desired format 
> from one of the supplied formats.
 
> > This is on Linux (GTK1). I looked at the clipboard calls, but on the first 
> > look of things I see no reason why it should be so slow, except maybe the
> > ClipboardGetFormats() call.
> 
> I only know about the Windows clipboard, not on other systems. The 
> graphics system should not be involved on any platform.
> 
> > The strange thing is that if something suitable is on the clipboard, 
> > the application responds normally.
> 
> Isn't there a method EnumClipboardFormats, which should return only the 
> currently available formats?

The HasFormat() function calls EnumClipboardFormats, among other things.
I'll investigate how it behaves if I call EnumClipboardFormats directly.

Michael.