Re: motion notify event messages.

["Shane Miller" <SMiller1 stvgb org>]

That's what I thought. 
Here's what I did.  I created the button and wrote down the pointer returned (136791384).  Then I created the 
ENTRY control and wrote down the pointer (136977848).  

When I held the left-mouse button down on each one and moved the mouse, I observed the GTKWidget value passed 
into the callback, along with the GDKEventMotion's X and Y coordinates.  The widget value was always the 
value that was returned from the creation of the control (the pointer value 136791384 or 136977848). However, 
the X and Y values were either relative to the control (the entry control) or relative to the Button's parent 
(the gtkwindow).

Any thoughts?  

Shane Miller


> > > Havoc Pennington <hp redhat com> 10/29/01 02:45PM >>>

"Shane Miller" <SMiller1 stvgb org> writes: 
> If I hold the left mouse button down over the ENTRY and move my
> mouse to the left, I get motion-notify events fired by the Entry.
> The x and y coords are based on the mouse postion within that entry
> control.  Meaning that if the control was 75 pixels wide and 10 high
> and I held the mouse button down over the right-bottom most pixel on
> the entry control and moved one pixel to the left, the mouse coord's
> reported in motion-notify would be 74,10 or something near that.
>  
> If I hold the left mouse button down over the BUTTON control and
> move my mouse to the left, I get motion-notify events fired by the
> button.  The x and y coords are based on the mouse postion within
> that FORM instead of the control.  Meaning that if the control was
> 75 pixels wide and 10 high and it's origin was at 50,50 on the form,
> and I held the mouse button down over the right-bottom most pixel on
> the button control and moved one pixel to the left, the mouse
> coord's reported in motion-notify would be 124,60 or something near
> that.
>
> Why is that?  Shouldn't they both report mouse coordinates based on
> the mouse position in the FORM or the CONTROL?  Is this a known
> issue or have we coded something incorrectly in Lazarus?

Motion coordinates should always be relative to the GdkWindow that was
initially clicked on (or that has the pointer grab). Both entry and
button have a GdkWindow of their own, so coords should be relative to
the widget. If that's not the case then something is wrong.

Havoc