Identify a valid parent for the specified widget
PtWidget_t * PtValidParent( PtWidget_t *widget_parent, PtWidgetClassRef_t *class_ref );
ph
This function determines the real parent widget for widgets of type class_ref, given that its parent is specified as widget_parent when created or reparented. Examples of a class_ref include PtWidget, PtBasic, PtLabel, PtMeter, and so on.
The real parent of a widget might not be the specified widget_parent in special circumstances where the specified parent widget redirects the child to an alternate parent. Some examples:
A pointer to the widget that will be the real parent of any widgets of type class_ref created in or reparented to widget_parent.
PtWidget_t * MyRedirector( PtWidget_t *widget ) { MyWidget_t *my = (MyWidget_t * ) widget; PtWidget_t *parent; if( ( parent = PtValidParent( my->scroll_area, widget->class_ref ) ) == widget ) return PtWidgetParent( widget ); return( parent ); /* * Returning my->scroll_area would allow the child * to be created as a direct child of my->scroll_area. * This would be undesirable because scroll_area is a * compound widget, which also needs to redirect its * children to work correctly. */ }
Photon
Safety: | |
---|---|
Interrupt handler | No |
Signal handler | No |
Thread | No |
PtFindGuardian(), PtGetParent(), PtGetParentWidget(), PtReparentWidget(), PtSetParentWidget(), PtWidgetParent()
“Ordering widgets” in the Managing Widgets in Application Code chapter of the Photon Programmer's Guide