bWidgets::bwScreenGraph::Builder Class Reference

Helper class to construct screen-graphs. More...

#include <Builder.h>

Public Types
template<typename _BuilderType = Builder>
using	BuildFunc = std::function< void(_BuilderType &)>
	A callable type to build a layout. More...

Public Member Functions
	Builder (LayoutNode &active_layout_node)
	Builder (ScreenGraph &screen_graph)
virtual	~Builder ()=default
void	setActiveLayout (bwScreenGraph::LayoutNode &)
	Activate a layout node. More...
template<typename _LayoutType , typename... _Args>
auto	addLayout (_Args &&... __args) -> LayoutNode &
	Add and activate a child node for a layout created in-place. More...
template<typename _LayoutType , typename... _Args>
auto	buildLayout (BuildFunc<> build_func, _Args &&... __args) -> LayoutNode &
	Build a sub-layout node in-place using build_func. More...
template<typename _LayoutType , typename _BuilderType , typename... _Args>
auto	buildLayout (BuildFunc< _BuilderType > build_func, _Args &&... __args) -> LayoutNode &
	Build a sub-layout node in-place using build_func. More...
template<typename _WidgetType , typename... _Args>
auto	addWidget (_Args &&... __args) -> _WidgetType &
template<typename _WidgetType , typename... _Args>
auto	addContainer (std::unique_ptr< bwLayoutInterface > layout, _Args &&... __args) -> ContainerNode &
template<typename _WidgetType , typename... _Args>
auto	buildContainer (BuildFunc<> build_func, std::unique_ptr< bwLayoutInterface > layout, _Args &&... __args) -> ContainerNode &
	Build a container node in-place using build_func. More...
template<typename _WidgetType , typename _BuilderType , typename... _Args>
auto	buildContainer (BuildFunc< _BuilderType > build_func, std::unique_ptr< bwLayoutInterface > layout, _Args &&... __args) -> ContainerNode &
	Build a container node in-place using build_func. More...

Static Public Member Functions
static void	setLayout (LayoutNode &node, std::unique_ptr< bwLayoutInterface > layout)
static void	setWidget (WidgetNode &node, std::unique_ptr< bwWidget > widget)
static auto	addWidget (LayoutNode &node, std::unique_ptr< bwWidget > widget) -> bwWidget &
template<typename _WidgetType , typename... _Args>
static auto	emplaceWidget (LayoutNode &node, _Args &&... __args) -> _WidgetType &
	Add child node for a widget created in-place. More...

Detailed Description

Helper class to construct screen-graphs.

Use this to create all screen-graphs or sub-trees.

• addFoo functions add a node and constructs its item (widget or layout) in-place. That means arguments are passed to the function are forwarded to the widget or layout constructor.
• buildFoo functions do the same but allow specifying a build-function for sub-layouts. This is the prefered way to construct sub-layouts, because the builder manages all state. For the caller it's a stateless way to build.

Member Typedef Documentation

BuildFunc

template<typename _BuilderType = Builder>

using bWidgets::bwScreenGraph::Builder::BuildFunc = std::function<void(_BuilderType&)>

A callable type to build a layout.

buildFoo functions use this to receive a callback for building their sub-layout. Can bind to a plain old function pointer, a function object (functor) or a lambda.

Constructor & Destructor Documentation

Builder() [1/2]

bWidgets::bwScreenGraph::Builder::Builder

(

LayoutNode &

active_layout_node

)

Builder() [2/2]

bWidgets::bwScreenGraph::Builder::Builder

(

ScreenGraph &

screen_graph

)

~Builder()

virtual bWidgets::bwScreenGraph::Builder::~Builder ( )

virtualdefault

Member Function Documentation

addContainer()

template<typename _WidgetType , typename... _Args>

auto bWidgets::bwScreenGraph::Builder::addContainer ( std::unique_ptr< bwLayoutInterface >  layout, _Args &&...  __args  ) -> ContainerNode&

inline

addLayout()

template<typename _LayoutType , typename... _Args>

auto bWidgets::bwScreenGraph::Builder::addLayout ( _Args &&...  __args ) -> LayoutNode&

inline

Add and activate a child node for a layout created in-place.

addWidget() [1/2]

template<typename _WidgetType , typename... _Args>

auto bWidgets::bwScreenGraph::Builder::addWidget ( _Args &&...  __args ) -> _WidgetType&

inline

addWidget() [2/2]

auto bWidgets::bwScreenGraph::Builder::addWidget ( LayoutNode &  node, std::unique_ptr< bwWidget >  widget  ) -> bwWidget&

static

buildContainer() [1/2]

template<typename _WidgetType , typename _BuilderType , typename... _Args>

auto bWidgets::bwScreenGraph::Builder::buildContainer ( BuildFunc< _BuilderType >  build_func, std::unique_ptr< bwLayoutInterface >  layout, _Args &&...  __args  ) -> ContainerNode&

inline

Build a container node in-place using build_func.

This override passes a custom builder type to the build_func (must inherit from Builder).

Only creates widget in-place, layout still needs to be created by the caller. Otherwise, we'd have to do perfect forwarding of parameters to multiple constructors. This can be done (e.g. see https://cpptruths.blogspot.com/2012/06/perfect-forwarding-of-parameter-groups.html) but in the end, just letting the caller create the layout is less verbose and easier to understand.

Parameters

build_func

Callback to create the subtree for this container.

buildContainer() [2/2]

template<typename _WidgetType , typename... _Args>

auto bWidgets::bwScreenGraph::Builder::buildContainer ( BuildFunc<>  build_func, std::unique_ptr< bwLayoutInterface >  layout, _Args &&...  __args  ) -> ContainerNode&

inline

Build a container node in-place using build_func.

This override passes the default builder type (Builder) to the build_func.

buildLayout() [1/2]

template<typename _LayoutType , typename _BuilderType , typename... _Args>

auto bWidgets::bwScreenGraph::Builder::buildLayout ( BuildFunc< _BuilderType >  build_func, _Args &&...  __args  ) -> LayoutNode&

inline

Build a sub-layout node in-place using build_func.

This override passes a custom builder type to the build_func (must inherit from Builder).

buildLayout() [2/2]

template<typename _LayoutType , typename... _Args>

auto bWidgets::bwScreenGraph::Builder::buildLayout ( BuildFunc<>  build_func, _Args &&...  __args  ) -> LayoutNode&

inline

Build a sub-layout node in-place using build_func.

This override passes the default builder type (Builder) to the build_func.

emplaceWidget()

template<typename _WidgetType , typename... _Args>

static auto bWidgets::bwScreenGraph::Builder::emplaceWidget ( LayoutNode &  node, _Args &&...  __args  ) -> _WidgetType&

inlinestatic

Add child node for a widget created in-place.

Simplifies creating and appending widgets. The arguments __args are forwarded to the widget constructor; a new node for it is added as child to node.

Without emplaceWidget():

using bWidgets::bwScreenGraph;
 
auto& widget = static_cast<bwLabel&>(Builder::addWidget<bwLabel>(
                   screen_graph, std::make_unique<bwLabel>("Foo", 0, 10)));
widget.foo();
// ...

With emplaceWidget():

using bWidgets::bwScreenGraph;
 
auto& widget = Builder::emplaceWidget<bwLabel>(screen_graph, "Foo", 0, 10);
widget.foo();
// ...

setActiveLayout()

void bWidgets::bwScreenGraph::Builder::setActiveLayout

(

bwScreenGraph::LayoutNode &

node

)

Activate a layout node.

Adding further items will add them as children to this node, until a different layout node is activated.

setLayout()

void bWidgets::bwScreenGraph::Builder::setLayout ( LayoutNode &  node, std::unique_ptr< bwLayoutInterface >  layout  )

static

setWidget()

void bWidgets::bwScreenGraph::Builder::setWidget ( WidgetNode &  node, std::unique_ptr< bwWidget >  widget  )

static

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

• bwidgets/screen_graph/Builder.h
• bwidgets/screen_graph/Builder.cc