kanzi::FocusScopeVisitor Class Reference

Focus scope visitor for UI scene traversal of focus scopes. More...

#include <kanzi/core.ui/input/focus_scope.hpp>

Inheritance diagram for kanzi::FocusScopeVisitor:

Public Member Functions
virtual Node::VisitorResult	operator() (const FocusChainNode &visitedElement)=0
	Overload of the parenthesis operator, returns the visit result of a visitedElement. More...
virtual	~FocusScopeVisitor ()=default
	Default destructor. More...

Detailed Description

Focus scope visitor for UI scene traversal of focus scopes.

To visit a focus scope using UI scene traversal:

• Create a focus scope visitor by deriving from this interface, and implement the parenthesis operator.
• Call the FocusScope::visitFocusScope() or the FocusScope::visitFocusChain() methods and pass your visitor as argument.

To find the last-focused node in a focus scope using the UI scene traversal method:

    auto scope = node->getFocusScopeInfo();
    auto focusedElement = FocusChainNode();
    auto visitor = [&focusedElement, &scope](auto& visitedElement)
    {
        if (visitedElement == scope->getLastFocused())
        {
            focusedElement = visitedElement;
            // Stop the visiting, as the last-focused node is found.
            return Node::VisitorAbort;
        }
        return Node::VisitorContinue;
    };
    auto wrapper = VisitorFunction(visitor);
    scope->visitFocusChain(wrapper);

To visit a focus scope using the iterated traversal method, see FocusScope::FocusChain.

Since

Kanzi 3.9.0

Constructor & Destructor Documentation

virtual kanzi::FocusScopeVisitor::~FocusScopeVisitor ( )

virtualdefault

Default destructor.

Member Function Documentation

virtual Node::VisitorResult kanzi::FocusScopeVisitor::operator() ( const FocusChainNode &  visitedElement )

pure virtual

Overload of the parenthesis operator, returns the visit result of a visitedElement.

Parameters

visitedElement

The visited focus chain element.

Returns

The result of the visit.

See also

Node::VisitorResult

Implemented in kanzi::VisitorFunction.

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The documentation for this class was generated from the following file:

• kanzi/core.ui/input/focus_scope.hpp