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Centrallix Documentation
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2.5 Obscure and Reveal
One important concept in a Centrallix application is the concept of Obscure and Reveal.
When is a widget considered to be "Revealed"?
A widget is considered to be "Revealed" if all of its containers are selected and/or visible. For tab controls, this means that the particular tab page is selected. For child windows, this means that the window is open (visible), even if it may be partially hidden by another window stacked on top of it. Thus, a table inside a tab page which is inside a childwindow would be revealed only if the childwindow is open (visible) and the particular tab page is selected in the tab control. In all other cases, the table would be considered "Obscured".
An objectsource (osrc) is a special case. It is considered to be revealed if any table or form (or part thereof) connected to the osrc is revealed.
How Obscure and Reveal affect an application...
Obscure and Reveal are used for two important things when it comes to data.
First, when an objectsource transitions from being Obscured to being Revealed, it has the option of automatically running its SQL query and loading its result set of objects (records). If 'autoquery' is set to 'onfirstreveal' for the osrc, this automatic query will happen only the first time the osrc becomes revealed. If set to 'oneachreveal', it happens every time the osrc transitions from obscured to revealed.
Second, when a form widget has unsaved data, and the entire form is about to transition from Revealed to Obscured, then the form has the opportunity to ask the user whether modifications should be saved, discarded, or whether the operation causing the Obscure should simply be canceled (such as preventing a childwindow from closing).
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