gtkmm  4.8.0
Public Types | Public Member Functions | Static Public Member Functions | Protected Member Functions | Related Functions | List of all members
Gtk::Filter Class Reference

Filtering items. More...

#include <gtkmm/filter.h>

Inheritance diagram for Gtk::Filter:
Inheritance graph
[legend]

Public Types

enum class  Match {
  SOME ,
  NONE ,
  ALL
}
 Describes the known strictness of a filter. More...
 
enum class  Change {
  DIFFERENT ,
  LESS_STRICT ,
  MORE_STRICT
}
 Describes changes in a filter in more detail and allows objects using the filter to optimize refiltering items. More...
 

Public Member Functions

 Filter (Filter && src) noexcept
 
Filteroperator= (Filter && src) noexcept
 
 ~Filter () noexcept override
 
GtkFilter * gobj ()
 Provides access to the underlying C GObject. More...
 
const GtkFilter * gobj () const
 Provides access to the underlying C GObject. More...
 
GtkFilter * gobj_copy ()
 Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs. More...
 
bool match (const Glib::RefPtr< Glib::ObjectBase > & item)
 Checks if the given item is matched by the filter or not. More...
 
Match get_strictness ()
 Gets the known strictness of filters. More...
 
Glib::SignalProxy< void(Change)> signal_changed ()
 

Static Public Member Functions

static GType get_type ()
 Get the GType for this class, for use with the underlying GObject type system. More...
 

Protected Member Functions

 Filter ()
 
void changed (Change change=Change::DIFFERENT)
 Notifies all users of the filter that it has changed. More...
 
virtual bool match_vfunc (const Glib::RefPtr< Glib::ObjectBase > & item)
 
virtual Match get_strictness_vfunc ()
 

Related Functions

(Note that these are not member functions.)

Glib::RefPtr< Gtk::Filterwrap (GtkFilter * object, bool take_copy=false)
 A Glib::wrap() method for this object. More...
 

Detailed Description

Filtering items.

A Gtk::Filter object describes the filtering to be performed by a Gtk::FilterListModel.

The model will use the filter to determine if it should include items or not by calling match() for each item and only keeping the ones that the function returns true for.

Filters may change what items they match through their lifetime. In that case, they will emit the signal_changed() signal to notify that previous filter results are no longer valid and that items should be checked again via match().

GTK provides various pre-made filter implementations for common filtering operations. These filters often include properties that can be linked to various widgets to easily allow searches.

However, in particular for large lists or complex search methods, it is also possible to subclass Gtk::Filter and provide one's own filter.

See also
Gtk::FilterListModel
Since gtkmm 3.98:

Constructor & Destructor Documentation

◆ Filter() [1/2]

Gtk::Filter::Filter ( Filter &&  src)
noexcept

◆ ~Filter()

Gtk::Filter::~Filter ( )
overridenoexcept

◆ Filter() [2/2]

Gtk::Filter::Filter ( )
protected

Member Function Documentation

◆ changed()

void Gtk::Filter::changed ( Change  change = Change::DIFFERENT)
protected

Notifies all users of the filter that it has changed.

This emits the signal_changed() signal. Users of the filter should then check items again via match().

Depending on the change parameter, not all items need to be changed, but only some. Refer to the Gtk::FilterChange documentation for details.

This function is intended for implementors of Gtk::Filter subclasses and should not be called from other functions.

Parameters
changeHow the filter changed.

◆ get_strictness()

Match Gtk::Filter::get_strictness ( )

Gets the known strictness of filters.

If the strictness is not known, Gtk::Filter::Match::SOME is returned.

This value may change after emission of the signal_changed() signal.

This function is meant purely for optimization purposes, filters can choose to omit implementing it, but Gtk::FilterListModel uses it.

Returns
The strictness of self.

◆ get_strictness_vfunc()

virtual Match Gtk::Filter::get_strictness_vfunc ( )
protectedvirtual

◆ get_type()

static GType Gtk::Filter::get_type ( )
static

Get the GType for this class, for use with the underlying GObject type system.

◆ gobj() [1/2]

GtkFilter* Gtk::Filter::gobj ( )
inline

Provides access to the underlying C GObject.

◆ gobj() [2/2]

const GtkFilter* Gtk::Filter::gobj ( ) const
inline

Provides access to the underlying C GObject.

◆ gobj_copy()

GtkFilter* Gtk::Filter::gobj_copy ( )

Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.

◆ match()

bool Gtk::Filter::match ( const Glib::RefPtr< Glib::ObjectBase > &  item)

Checks if the given item is matched by the filter or not.

Parameters
itemThe item to check.
Returns
true if the filter matches the item and a filter model should keep it, false if not.

◆ match_vfunc()

virtual bool Gtk::Filter::match_vfunc ( const Glib::RefPtr< Glib::ObjectBase > &  item)
protectedvirtual

◆ operator=()

Filter& Gtk::Filter::operator= ( Filter &&  src)
noexcept

◆ signal_changed()

Glib::SignalProxy<void(Change)> Gtk::Filter::signal_changed ( )
Slot Prototype:
void on_my_changed(Change change)

Flags: Run Last

Emitted whenever the filter changed.

Users of the filter should then check items again via Gtk::Filter::match().

Gtk::FilterListModel handles this signal automatically.

Depending on the change parameter, not all items need to be checked, but only some. Refer to the Gtk::FilterChange documentation for details.

Parameters
changeHow the filter changed.

Friends And Related Function Documentation

◆ wrap()

Glib::RefPtr< Gtk::Filter > wrap ( GtkFilter *  object,
bool  take_copy = false 
)
related

A Glib::wrap() method for this object.

Parameters
objectThe C instance.
take_copyFalse if the result should take ownership of the C instance. True if it should take a new copy or ref.
Returns
A C++ instance that wraps this C instance.