When you assign a hide formula to all the content in a tab, the tab disappears. There is no control that hides the tab independently of hide formulas for the content.
Tip: The easiest way I have found to write reliable hide formulas is to write a condition that represents the state in which the content should appear and that is reliable (e.g. there will never be errors in those field values), then wrap the condition in a NOT.
!(Status = "Open" & Approval = "")
The data controlled by this formula will show if the Status is Open and the Approval is blank.
This is not actually true. You can use the above method, it is just not the only method. On the properties of a tabbed table, you can choose to "programmatically" change tabs, and then choose not to display the tabs. Then use a button on the tab to go to the tab you want. I have used this many times to make "wizard" like dialog boxes and all kinds of things.
To change a tab programmatically, just use the hidden table name - $TableName, assign it (it is technically a field) the value of the tab name you want and do a refreshhideformulas.
This is documented in help quite well, but let me know if you need more specifics. Also, this has been a feature since tabbed tables (version 5 I believe, could have been 6 though)
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