Tab control event Keypress

Hello,
I'm using a Tab control and can't find out how to handle the following situation.
We know that when operating a Tab control we can jump from Tab to Tab by pressing <Ctrl-Tab>.
When at the last Tab I would like to jump to another conbtrol and not again to the first Tab.
Unfortunately in this situation <Ctrl-Tab> doesn't generate an EVENT_KEYPRESS.
Is there a way to handle this situation?
Solved!
Go to Solution.

I don't understand why you cannot get the keypress event: I have tried to modify TabExample example installing a callback on the tab control and properly get the keypress event on Ctrl+Tab. Here the code for the tab control callback function:
int CVICALLBACK TabCallback (int panel, int control, int event,
void *callbackData, int eventData1, int eventData2)
int nextCtrl, lastTab, pageIdx, virtualKey, modifierKey;
if (event == EVENT_KEYPRESS) {
GetActiveTabPage (panel, control, &pageIdx);
GetNumTabPages (panel, control, &lastTab);
lastTab--; // Zero-based index
virtualKey = eventData1 & VAL_VKEY_MASK;
modifierKey = eventData1 & VAL_MODIFIER_KEY_MASK;
// Properly handle Ctrl+Tab
if (modifierKey == VAL_MENUKEY_MODIFIER && virtualKey == VAL_TAB_VKEY && pageIdx == lastTab) {
GetCtrlAttribute (panel, PANEL_TAB, ATTR_NEXT_CTRL, &nextCtrl);
SetActiveCtrl (panel, nextCtrl);
return 1; // Swallow the keypress event so that active page doesn't change
return 0;
Alternatively, you can handle the situation inside a panel callback:
int CVICALLBACK PanelCallback (int panel, int event, void *callbackData,
int eventData1, int eventData2)
int lastTab, control, pageIdx, virtualKey, modifierKey, nextCtrl;
if (event == EVENT_KEYPRESS) {
if ((control = GetActiveCtrl (panel)) == PANEL_TAB) {
GetActiveTabPage (panel, control, &pageIdx);
GetNumTabPages (panel, control, &lastTab);
// eventData1: a 4-byte integer consisting of 3 fields: 0x00MMVVAA
// MM = the modifier key, VV = the virtual key, AA = the ASCII key
// key masks are defined in userint.h
virtualKey = eventData1 & VAL_VKEY_MASK;
modifierKey = eventData1 & VAL_MODIFIER_KEY_MASK;
// Properly handle Ctrl+Tab
if (modifierKey == VAL_MENUKEY_MODIFIER && virtualKey == VAL_TAB_VKEY && (pageIdx == lastTab - 1)) {
GetCtrlAttribute (panel, PANEL_TAB, ATTR_NEXT_CTRL, &nextCtrl);
SetActiveCtrl (panel, nextCtrl);
return 1;
return 0;
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Dynamic event registration wont work with Tab control

In LTR volume 11 No1 we find the "Dynamic Event Handling.vi".
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Is there a solution to this problem?
Scientia est potentia!
Attachments:
Dynamic_Event_Registration.vi ‏51 KB
Dynamic_Event_Registration(controls_on_Tab).vi ‏64 KB

Yes. The first stage of the code registers mouse down events for all the controls. When you added a tab control that meant that a mouse down event was registered for the tab as well. So now when you click on an object on the tab LabVIEW must decide whether to fire the mouse down on the tab-event, or the mouse down on the object on the tab event...It goes for the first but since there is no description for the tab no dialog will be displayed. If you add a description for the tab you'll see that it fires the event with the tab and you get a dialog with the tab description.
So - how to fix. Well, it's not that simple, one might think that to exclude the reference to the tab when you register the events would do the trick, but it rather seems that LV will always t
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Hi,
I have a Tab control with 4 tabs and I would like when I go to a specific tab all the contents of that tab being updated. Could you please help me with this?
How should I set the event structure
Thanks

Tab Control->Value Change is the event you want. You can then use a case structure to do whatever you need it to based on the "New Value".
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Events & Tab Control Navigation Buttons

In the attached example, I use a Tab Control with several pages, some of them being hidden.
To access them, I use the navigation buttons on the top right corner of the Tab.
Unfortunately, changing the pages using these navigation buttons does not trigger a "Value Change" event as it does when changing by clicking on the desired page.
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Attachments:
TabControl.vi ‏26 KB

That's a good one, NI should have made the control fire the value change event in that case too. You could make a timeout event and check the value there (and fire an event for it if you wanted) but that's not very elegant. Personally I would go for multiline tabs, it's not often you see a tab with a scrollbar like that so the user's would probably find it more intuitive to have multiline tabs or another level of selection.
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Hi!
I want to be able to update the code contained within an event structure by a tab control value change, in addition to the usual bool controller in the UI.
The problem is that the event structure don't seem to run when the bool has a value change for the tab control. I have made a short .vi to demonstrate. A counter is placed in the Event structure so it is possible to see if it is running or not.
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Is my avatar the dog from the fraggle rock?
Attachments:
forum_question.vi ‏12 KB

Here is a version of your code using a Value Signaling property node.
I "think" it does what you want ...
steve
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Attachments:
forum_question_mod 2009.vi ‏15 KB

How to control the tab control using event structure?

Hi,
I am using tab control and event structure in the program.
When i run the application event is not happening for the active page.
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For more clarification i am attaching the code "Test Control Tab using Event Structure.vi"
Attachments:
Test Control Tab using Event Structure.vi ‏52 KB

You have a basic misunderstanding of dataflow. Maybe you should start with some tutorials or study some of the examples that ship with LabVIEW.
The event structure belongs inside the while loop, and not vice versa. RIght now, the event structure only runs exactly once and never again.
If the stop is pressed first, the VI will stop. Game over.
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you were closer to a reasonable program in the other thread:
http://forums.ni.com/ni/board/message?board.id=170&view=by_date_ascending&message.id=287905
Have you tried execution highlighting? Maybe things would become more clear of you do.
LabVIEW Champion . Do more with less code and in less time .

How to progammatically show a specific page of a tab control

Hei,
i have a tab control, from which i want to display a specific page if a specific event occured.
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of course!!
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CursorLegendTabControlBUG.vi ‏27 KB

Good idea. It doesn't work exactlly, but gave me the idea for how to work around. It appears even if you have a tab value change event doing the same thing the Cursor X Position numeric indicator value change event, the cursor legend X value will not change. You can even try entering the same value in the indicator and pressing return after switching tabs, the cursor legend will not update. It thinks for some reason it is on the correct index. I made a Tab Value change event that first moves the cursor to the next index, then moves the cursor back to the correct index. Ugly but works. Hopefully in the next ver of LV they will have fixed a lot of these cursor bugs; there is definitely some work to be done (i.e. fixing cursor X position for XY graphs, an extremelly annoying bug)
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Message Edited by miguelc on 02-23-2007 03:49 PM
Message Edited by miguelc on 02-23-2007 03:50 PM
Attachments:
CursorLegendTabControlBUG_wrkaround.vi ‏34 KB

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Solved!
Go to Solution.

I decided to take some time (probably way too much time!) to try this out and prove it would work. See the attachment in LV 8.5.1.
I used arrays and control references to make the code as scalable as possible. I added several spaces at the end of each label name so that there was some room to place a very small LED.
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Message Edited by Ravens Fan on 09-17-2008 11:59 PM
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TabLEDexample.vi ‏44 KB

Tab Control/Display Data

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Solved!
Go to Solution.

Hi Splee,
Please view the attached vi, I believe it's doing what you've asked. You can invoke properties using property node in order to change the value of variables.
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Check your page selection technique.
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Create a log in tab in tab control and to create one of the tab is disabled and grayed

Hello there
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Solved!
Go to Solution.
Attachments:
Untitled 112.vi ‏19 KB

Hi,
Aaa.. the blue box is an Enumeration Constant. Because I've used something like this you cannot change the name of the Tabs. To fix it:
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Attachments:
password.vi ‏35 KB

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tst wrote:
Tell me if you still think this makes sense.
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Message Edited by altenbach on 03-15-200612:42 PM
LabVIEW Champion . Do more with less code and in less time .
Attachments:
init.png ‏3 KB

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Attachments:
tabcontrol autoscale.vi ‏32 KB

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Lock Tabs with Tab Control

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Message Edited by jcarmody on 04-17-2009 08:03 PM
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Attachments:
Example_VI_BD.png ‏5 KB
Untitled 1.vi ‏12 KB

Tab control event Keypress

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