MATLAB Central Newsreader - Interrupt for Current Figure Change

Interrupt for Current Figure Change

Ian Woloschin — Thu, 01 Jun 2006 09:36:41 -0400

Is it possible to detect when the current figure has changed through
an interrupt/callback?

I have a gui control figure that enables features (such as panning)
in other figures, but for simplicity, only one figure is active at
any given time. At this point, you need to go to the control figure
to specify the active figure, but I'd like for the control gui to
automatically update if the current figure switches from, say, figure
1 to figure 2.

Re: Interrupt for Current Figure Change

Perry — Thu, 01 Jun 2006 11:25:44 -0400

Ian,

I think what you need here is an 'OnFocus' function, i.e. a function
that is called only when the user selcts it, i.e. the figures becomes
'the focus'. The bad part is, I'm not sure Matlab enables you to
specify one. Sure you can 'get the current figure' with gcf, but you
still need to initiate this command when the figure becomes the
focus.

The nearest thing I can find to achieve this is to specify a
WindowButtonDownFcn callback. In this function you could set some
applicationdata that could be read by your control figure as to which
figure was last active.

NOTE : This function is called when the user presses the mouse button
in the figure. It does NOT get called if the user selects the title
bar or and axis within the figure, so it's not going to work 100% of
the time. As I say, Matlab (I don't think) provides an 'OnFocus'
callback option.

Perry

Ian Woloschin wrote:
>
>
> Is it possible to detect when the current figure has changed
> through
> an interrupt/callback?
>
> I have a gui control figure that enables features (such as panning)
> in other figures, but for simplicity, only one figure is active at
> any given time. At this point, you need to go to the control
> figure
> to specify the active figure, but I'd like for the control gui to
> automatically update if the current figure switches from, say,
> figure
> 1 to figure 2.

Re: Interrupt for Current Figure Change

Ian Woloschin — Thu, 01 Jun 2006 12:43:10 -0400

I've considered trying to use the WindowButtonDownFcn, but I haven't
done any serious work on that yet. I'm actually using the
WindowButtonDownFcn already, but if I compare the figure that's
active to the one I think should be active, that would let me know if
the user made a new figure the current figure.

However, this does not take into account if they alt-tabbed into the
figure or clicked the title bar, etc, as you said. For my purposes,
the above may be enough as my program requires you to click on the
axes eventually to do anything, but it's a rather silly way to go
about writing a program.

Perry wrote:
>
>
> Ian,
>
> I think what you need here is an 'OnFocus' function, i.e. a
> function
> that is called only when the user selcts it, i.e. the figures
> becomes
> 'the focus'. The bad part is, I'm not sure Matlab enables you to
> specify one. Sure you can 'get the current figure' with gcf, but
> you
> still need to initiate this command when the figure becomes the
> focus.
>
> The nearest thing I can find to achieve this is to specify a
> WindowButtonDownFcn callback. In this function you could set some
> applicationdata that could be read by your control figure as to
> which
> figure was last active.
>
> NOTE : This function is called when the user presses the mouse
> button
> in the figure. It does NOT get called if the user selects the title
> bar or and axis within the figure, so it's not going to work 100%
> of
> the time. As I say, Matlab (I don't think) provides an 'OnFocus'
> callback option.
>
> Perry
>
> Ian Woloschin wrote:
>>
>>
>> Is it possible to detect when the current figure has changed
>> through
>> an interrupt/callback?
>>
>> I have a gui control figure that enables features (such as
> panning)
>> in other figures, but for simplicity, only one figure is active
> at
>> any given time. At this point, you need to go to the control
>> figure
>> to specify the active figure, but I'd like for the control gui
to
>> automatically update if the current figure switches from, say,
>> figure
>> 1 to figure 2.

Re: Interrupt for Current Figure Change

Perry — Thu, 01 Jun 2006 14:27:10 -0400

Ian,

I agree it probably isn't a good way to go, but I put a post up
myself asking if anyone knows of an 'OnFocus' callback, but no
replies as yet. I'm curious myself now as it would be a handy
function to have access to. I'm Just using a student version, R14 so
maybe later versions of Matlab have this facility.

Perry

>
>
> I've considered trying to use the WindowButtonDownFcn, but I
> haven't
> done any serious work on that yet. I'm actually using the
> WindowButtonDownFcn already, but if I compare the figure that's
> active to the one I think should be active, that would let me know
> if
> the user made a new figure the current figure.
>
> However, this does not take into account if they alt-tabbed into
> the
> figure or clicked the title bar, etc, as you said. For my
> purposes,
> the above may be enough as my program requires you to click on the
> axes eventually to do anything, but it's a rather silly way to go
> about writing a program.
>
> Perry wrote:
>>
>>
>> Ian,
>>
>> I think what you need here is an 'OnFocus' function, i.e. a
>> function
>> that is called only when the user selcts it, i.e. the figures
>> becomes
>> 'the focus'. The bad part is, I'm not sure Matlab enables you
to
>> specify one. Sure you can 'get the current figure' with gcf,
but
>> you
>> still need to initiate this command when the figure becomes the
>> focus.
>>
>> The nearest thing I can find to achieve this is to specify a
>> WindowButtonDownFcn callback. In this function you could set
some
>> applicationdata that could be read by your control figure as to
>> which
>> figure was last active.
>>
>> NOTE : This function is called when the user presses the mouse
>> button
>> in the figure. It does NOT get called if the user selects the
> title
>> bar or and axis within the figure, so it's not going to work
100%
>> of
>> the time. As I say, Matlab (I don't think) provides an
'OnFocus'
>> callback option.
>>
>> Perry
>>
>> Ian Woloschin wrote:
>>>
>>>
>>> Is it possible to detect when the current figure has
changed
>>> through
>>> an interrupt/callback?
>>>
>>> I have a gui control figure that enables features (such as
>> panning)
>>> in other figures, but for simplicity, only one figure is
> active
>> at
>>> any given time. At this point, you need to go to the
control
>>> figure
>>> to specify the active figure, but I'd like for the control
> gui
> to
>>> automatically update if the current figure switches from,
> say,
>>> figure
>>> 1 to figure 2.

Re: Interrupt for Current Figure Change

Ian Woloschin — Thu, 01 Jun 2006 15:14:57 -0400

I'm just using R13 now, as my employer doesn't have a later version.
At school I use R14SP3, I think, but that doesn't help me much.

I've kind of put this part of my project on the back burner for now,
though I keep making other things work so I'll probably be back to
this in another day or two, heh.

I'm curious if there is a hidden feature that Matlab uses to do this,
that we might be able to (in a rather ugly manner) hitch onto and use
for our own purposes.

Perry wrote:
>
>
> Ian,
>
> I agree it probably isn't a good way to go, but I put a post up
> myself asking if anyone knows of an 'OnFocus' callback, but no
> replies as yet. I'm curious myself now as it would be a handy
> function to have access to. I'm Just using a student version, R14
> so
> maybe later versions of Matlab have this facility.
>
> Perry
>
>>
>>
>> I've considered trying to use the WindowButtonDownFcn, but I
>> haven't
>> done any serious work on that yet. I'm actually using the
>> WindowButtonDownFcn already, but if I compare the figure that's
>> active to the one I think should be active, that would let me
> know
>> if
>> the user made a new figure the current figure.
>>
>> However, this does not take into account if they alt-tabbed
into
>> the
>> figure or clicked the title bar, etc, as you said. For my
>> purposes,
>> the above may be enough as my program requires you to click on
> the
>> axes eventually to do anything, but it's a rather silly way to
go
>> about writing a program.
>>
>> Perry wrote:
>>>
>>>
>>> Ian,
>>>
>>> I think what you need here is an 'OnFocus' function, i.e. a
>>> function
>>> that is called only when the user selcts it, i.e. the
figures
>>> becomes
>>> 'the focus'. The bad part is, I'm not sure Matlab enables
you
> to
>>> specify one. Sure you can 'get the current figure' with
gcf,
> but
>>> you
>>> still need to initiate this command when the figure becomes
> the
>>> focus.
>>>
>>> The nearest thing I can find to achieve this is to specify
a
>>> WindowButtonDownFcn callback. In this function you could
set
> some
>>> applicationdata that could be read by your control figure
as
> to
>>> which
>>> figure was last active.
>>>
>>> NOTE : This function is called when the user presses the
> mouse
>>> button
>>> in the figure. It does NOT get called if the user selects
the
>> title
>>> bar or and axis within the figure, so it's not going to
work
> 100%
>>> of
>>> the time. As I say, Matlab (I don't think) provides an
> 'OnFocus'
>>> callback option.
>>>
>>> Perry
>>>
>>> Ian Woloschin wrote:
>>>>
>>>>
>>>> Is it possible to detect when the current figure has
> changed
>>>> through
>>>> an interrupt/callback?
>>>>
>>>> I have a gui control figure that enables features (such
> as
>>> panning)
>>>> in other figures, but for simplicity, only one figure
is
>> active
>>> at
>>>> any given time. At this point, you need to go to the
> control
>>>> figure
>>>> to specify the active figure, but I'd like for the
> control
>> gui
>> to
>>>> automatically update if the current figure switches
from,
>> say,
>>>> figure
>>>> 1 to figure 2.