gui2::placer_base Class Reference

Base class for the placement helper. More...

#include <placer.hpp>

Inheritance diagram for gui2::placer_base:

Public Member Functions
virtual	~placer_base ()
virtual void	initialize ()=0
	Initialises the placer. More...
virtual void	add_item (const point &size)=0
	Adds a item to be placed. More...
virtual point	get_size () const =0
	Gets the required size of all items. More...
virtual point	get_origin (const unsigned index) const =0
	Gets the origin for an item. More...

Static Public Member Functions
static placer_base *	build (const grow_direction::type grow_dir, const unsigned parallel_items)
	Builder function. More...

Detailed Description

Base class for the placement helper.

The normal operation for the usage of the class is:

• Call initialize().
• For every visible child item call add_item() with the wanted size of the widget. Once this is done the required size for all children can be retrieved with get_size(). It is also possible to place all children now. In order to do so loop again over all children in the same order as add_item() and call get_origin(). The index parameter is an increasing counter.

Note

The origins can only be retrieved after all items are added since the adding of a later item may influence a previous item. E.g. in a vertical list with two columns the position of the second column depends on the width of the first and a later row may have a wider column 1 as an earlier row.

Definition at line 51 of file placer.hpp.

Constructor & Destructor Documentation

~placer_base()

gui2::placer_base::~placer_base ( )

virtual

Definition at line 39 of file placer.cpp.

Member Function Documentation

add_item()

virtual void gui2::placer_base::add_item ( const point &  size )

pure virtual

Adds a item to be placed.

Parameters

size	The required size for the item.

Implemented in gui2::implementation::placer_vertical_list, and gui2::implementation::placer_horizontal_list.

build()

placer_base * gui2::placer_base::build ( const grow_direction::type  grow_dir, const unsigned  parallel_items  )

static

Builder function.

Precondition

parallel_items > 0

Parameters

grow_dir	The direction in which the items will be added.
parallel_items	The direction perpendicular towards the grow direction has a fixed number of items. This value sets that limit. For a list containing only horizontally or vertically placed items the value should be 1.

Definition at line 27 of file placer.cpp.

get_origin()

virtual point gui2::placer_base::get_origin ( const unsigned  index ) const

pure virtual

Gets the origin for an item.

Parameters

index

The index of the item whose origin to return. The index is the index of the call to add_item().

Returns

The origin where to place the widget.

Implemented in gui2::implementation::placer_vertical_list, and gui2::implementation::placer_horizontal_list.

get_size()

virtual point gui2::placer_base::get_size ( ) const

pure virtual

Gets the required size of all items.

Returns

The required size.

Implemented in gui2::implementation::placer_vertical_list, and gui2::implementation::placer_horizontal_list.

initialize()

virtual void gui2::placer_base::initialize ( )

pure virtual

Initialises the placer.

When the placement needs to be calculated the state often needs to be reset, items are placed, removed or changed visibility causing the old placement to be invalid.

Implemented in gui2::implementation::placer_vertical_list, and gui2::implementation::placer_horizontal_list.

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

• gui/core/placer.hpp
• gui/core/placer.cpp