Subpanel issues? 
Author Message
 Subpanel issues?

I am embarking on a project that would do well with extensive use of
subpanels. What problems (or issues) have you run into. I already
found out that you can't change the autoscaling of a graph in a
subpanel by right clicking on the graph...

Anything else (important) lurking in the weeds?


Sun, 11 Dec 2005 03:46:00 GMT  
 Subpanel issues?
Here is one thing I've noticed: If you have a graph displayed through
a subpanel, the names of the axes may be blacked out.  I looked into
it and found that this is because it is showing the background of the
subpanel.  You need to open the VI which is actually being displayed
and set the background color of the axis name (with the set color
tool) to be the same color as the background of the graph (or whatever
color you prefer).

Sun, 11 Dec 2005 22:14:54 GMT  
 Subpanel issues?
You're right, come to think of it I saw that too.


Sun, 11 Dec 2005 22:44:40 GMT  
 Subpanel issues?
I just realized that I had inadvertenly written "background."  You
want to set the foreground to a particular color.  That will make it
viewable when it's displayed through a subpanel.

Sun, 11 Dec 2005 23:01:30 GMT  
 Subpanel issues?
I have been playing with this for a few days and have found a few
things that are perhaps underdocumented and which might be helpful...

First, subpanels work great! Very cool indeed!

Second, there are a couple concepts that you need to wrap your head
around. To begin, even though it looks like you are making calls to
the subpanel VI you really aren't--you're just observing it's front
panel. This is purely speculation, but I wouldn't be suprised to find
out that the technology underlying subpanels is very similar to that
which drives the remote frontpanel capability in LV.

This distinction becomes important when you need the VI making the
subpanel calls to actually interact with the subpanel VIs (i.e. pass
data back and forth, reference one another, etc). The examples that
ship with LV show making calls using an Open VI Reference call to get
a reference to the target VI. This means that the subpanel doesn't
know it's be accessed as a subpanel, as a result the "calling" VI
doesn't appear in the subpanel's call chain.

Because the appearance of the subpanel VI's front panel was
psychologically stronger that the fact of how the code was connecting
to the subpanel VI, I was initially fooled and reported it as a
possible bug--after all it sure seemed like I was calling the other
VI. But it now seems that this is the proper behavior given the type
of reference opened to the subpanel VI. The program making the
subpanel calls (if that's even the right term) was connected to the
subpanel vi on some level, but it wasn't linked to it in the
programming sense, hence its absence from the call chain.

If however, you do a call-by-reference, in that case you are actually
linking to the subpanel vi so you can pass data through connector
panes and the call chain shows the VI making the subpanel connection.
As you would expect with or without a subpanel to provide a view of
the front panel.

Hope this helps anyone else working with this functionality. I'll keep
ya'll posted if I come across anything else that might be helpful.


Fri, 23 Dec 2005 12:17:30 GMT  
 Subpanel issues?
> panel. This is purely speculation, but I wouldn't be suprised to find
> out that the technology underlying subpanels is very similar to that
> which drives the remote frontpanel capability in LV.

Actually, the subPanel feature is not at all related to the Remote Panel
Viewer.  Instead, the better mental model to have is that of dynamically
called popup panels.  You load the subVI using VI server, and you have a
choice to open it and run/call it in a popup panel, or in a subPanel.
The VI will run and be left open using rules very similar to the popup
panel, but it doesn't draw into its own window, instead it shares a
rectangle of the owning window/control.

Greg McKskle

Sat, 24 Dec 2005 20:47:54 GMT  
 [ 6 post ] 

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