property nodes not updating indicators on Tab

[ade77]

Something weird is going on with my tab control. My program loads a file and updates two xy graphs

1.  I have 3 pages on the tab

2. one xy graph is on page2

3 another xy graph is on page3

When I start the program, I prefer to have page1 visible, at which time it loads the file.

Now, after the file load is complete, I now switch to page2 or page3, but to my surprise,  the property node I set with the xy graphs are not implemented.

Now what is weird is that if I let page2 or page3 be visible before the file is completely read, the property node will update for the respective xy graph.

I am not sure if this is a bug, or I do not know what is going on.

[F._Schubert]

Can you post some code to demonstrate this behavour, so others can confirm your issue?

Felix

[johnsold]

Indicators which are not visible may not be updated.  This has been the case for many versions of LV.  I think it may have been an attempt to optimize graphics performance.  I do not recall whether this occurs with tab pages as it does for invisible indicators, but it could be the same underlying concept.

To work around: Force a write to the graph when the tab page changes.

Lynn

[ade77]

Unfortunately, I can not attach the code, some confidential info.

Thanks Johnsold. I think it is the same concept, becuase I was trying to update some properties on  the xy graph, and it is not visible at the time the file is completely loaded.

I will try your suggestion.

[Ben]

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@ade77 wrote:

Unfortunately, I can not attach the code, some confidential info.

Thanks Johnsold. I think it is the same concept, becuase I was trying to update some properties on  the xy graph, and it is not visible at the time the file is completely loaded.

I will try your suggestion.

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...and if that does not work search on "Jiggle the handle" to find the threads where I have helped others with similar issues.

Q:

Wht version of LV ?

Ben

[ade77]

Thanks Ben

I am using LV 2010. However, I still believe National Instrument should address this issue more closely.  I agreed it will take unneccessary CPU , if the indicator is not visible, however, when I choose to make the tab visible, then the indicator or graph should include all the properties I expect to get.....----- but it is not doing that

otherwise, it should not be NI business to check or not if it is going to take CPU  memory or not. Since the programmer have indicated he wants to put those properties into the graph or indicators, let the programmer worry about his CPU been consumed

[Ben]

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@ade77 wrote:

Thanks Ben

I am using LV 2010. However, I still believe National Instrument should address this issue more closely.  I agreed it will take unneccessary CPU , if the indicator is not visible, however, when I choose to make the tab visible, then the indicator or graph should include all the properties I expect to get.....----- but it is not doing that

otherwise, it should not be NI business to check or not if it is going to take CPU  memory or not. Since the programmer have indicated he wants to put those properties into the graph or indicators, let the programmer worry about his CPU been consumed

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I am not NI and would have to have been in the room when these bugs get scheduled for a fix so I can only speculate about why these types of bugs keep coming up to be squashed and then latter pop out another hole.

The philosophy behinf the tab control is similar but looking back to what we had to do to implement what "looked like" a tab control (before it was invented) we had to hide/show groups of objects to achieve the same effect. By exposing the Tab control (a way of grouping FP objects) NI has saved me a lot of work. The saved work has extended to including code to decide if an update shouldb e applied or not. When it works right it is way cool.

Here is a bit of a challenge solved by the tabs that would be a real pain.

A Chart displaying possibly days with of readings. In its current form and the updates are working, after five days you can switch to that tab and you will see what was last written there concidering chart history scaling etc.

If we were to write that type of functionality by deciding we should now update that tab, we would have to buffer all of the updates to apply them.

The lack of updates is a pain I agree, but throwing out the baby with the bath water ...

Take care,

Ben