wxPersistentWindow< T > Class Template Reference

#include <wx/persist/window.h>

Inheritance diagram for wxPersistentWindow< T >:

Detailed Description

template<class T>
class wxPersistentWindow< T >

Base class for persistent windows.

Compared to wxPersistentObject this class does three things:

• Most importantly, wxPersistentWindow catches wxWindowDestroyEvent generated when the window is destroyed and saves its properties automatically when it happens.
• It implements GetName() using wxWindow::GetName() so that the derived classes don't need to do it.
• It adds a convenient wxPersistentWindow::Get() accessor returning the window object of the correct type.

Public Types
typedef T	WindowType
	The type of the associated window.

Public Member Functions
	wxPersistentWindow (WindowType *win)
	Constructor for a persistent window object.
WindowType *	Get () const
virtual wxString	GetName () const
	Implements the base class pure virtual method using wxWindow::GetName().
Public Member Functions inherited from wxPersistentObject
	wxPersistentObject (void *obj)
	Constructor takes the object which we're associated with.
virtual	~wxPersistentObject ()
	Trivial but virtual destructor.
void *	GetObject () const
	Return the associated object.
virtual void	Save () const =0
	Save the object properties.
virtual bool	Restore ()=0
	Restore the object properties.
virtual wxString	GetKind () const =0
	Returns the string uniquely identifying the objects supported by this adapter.

Protected Member Functions
bool	SaveCoord (const wxString &name, int value) const
	Save a coordinate, i.e.
bool	RestoreCoord (const wxString &name, int *value)
	Restore a coordinate saved by SaveCoord().
Protected Member Functions inherited from wxPersistentObject
template<typename T>
bool	SaveValue (const wxString &name, T value) const
	Save the specified value using the given name.
template<typename T>
bool	RestoreValue (const wxString &name, T *value)
	Restore a value saved by SaveValue().

Member Typedef Documentation

WindowType

template<class T>

typedef T wxPersistentWindow< T >::WindowType

The type of the associated window.

Constructor & Destructor Documentation

wxPersistentWindow()

template<class T>

wxPersistentWindow< T >::wxPersistentWindow

(

WindowType *

win

)

Constructor for a persistent window object.

The constructor uses wxEvtHandler::Bind() to catch wxWindowDestroyEvent generated when the window is destroyed and call wxPersistenceManager::SaveAndUnregister() when this happens. This ensures that the window properties are saved and that this object itself is deleted when the window is.

Member Function Documentation

Get()

template<class T>

WindowType * wxPersistentWindow< T >::Get ( ) const

inline

GetName()

template<class T>

virtual wxString wxPersistentWindow< T >::GetName ( ) const

virtual

Implements the base class pure virtual method using wxWindow::GetName().

Notice that window names are usually not unique while this function must return a unique (at least among the objects of this type) string. Because of this you need to specify a non-default window name in its constructor when creating it or explicitly call wxWindow::SetName() before saving or restoring persistent properties.

Implements wxPersistentObject.

RestoreCoord()

template<class T>

bool wxPersistentWindow< T >::RestoreCoord ( const wxString & name, int * value )

protected

Restore a coordinate saved by SaveCoord().

If the DPI in which the coordinate is expressed is different from the DPI at which it had been saved, it is rescaled accordingly. If the latter is unknown, e.g. because the value was saved by a version of wxWidgets older than 3.3.4, the coordinate is restored unchanged.

As explained in SaveCoord() documentation, no DPI is stored under the platforms using DPI-independent pixels, so this function simply behaves as wxPersistentObject::RestoreValue() there.

Parameters

name	The same name as was used by SaveCoord().
value	Non-nullptr pointer to the variable to fill with the saved value if it was read successfully, which is not modified otherwise.

Returns

true if the value was successfully read or false if it was not found or an error occurred.

Since

3.3.4

SaveCoord()

template<class T>

bool wxPersistentWindow< T >::SaveCoord ( const wxString & name, int value ) const

protected

Save a coordinate, i.e.

either a position or a size, in pixels.

This function must be used instead of wxPersistentObject::SaveValue() for the values representing a size or a position in pixels, as it also stores the DPI in which the coordinate is expressed, allowing RestoreCoord() to rescale it if the DPI changes when the coordinate is restored later.

Note that under the platforms using DPI-independent pixels, such as wxGTK and wxOSX, the saved values don't change with the DPI and so no DPI is stored for them at all, meaning that they are never rescaled.

Also note that the values which are not really expressed in pixels, such as the special value -1 often used to indicate the absence of a value, are not affected by the rescaling and can be saved using this function too.

Parameters

name	The name of the value in the configuration file.
value	The value to save.

Returns

true if the value was saved or false if an error occurred.

Since

3.3.4