Class: TVirtualKeyboard

Declaration: Keyboards.h

Taxonomy Categories:

Member Functions:

Interface Category:

API.

Inherits From:

None.

Inherited By:

None.

Purpose:

Abstract base class that defines basic protocol for virtual keyboards.

Instantiation:

Not instantiated directly.

Deriving Classes:

Includes both surrogate (TVirtualKeyboardHandle) and implementation (TStandardEditableVirtualKeyboard) classes.

Concurrency:

Not multithread safe.

Resource Use:

No special requirements.

Member Function: TVirtualKeyboard::SetLocalizableName

virtual void SetLocalizableName (const TLocalizableName & name)

Interface Category:

API.

Purpose:

Specifies a localizable name for a transcoder.

Calling Context:

Typically called by clients who are creating a transcoder and want to give it a localizable name.

Parameters:

const TLocalizableName & name -The human-readable, localizable name.

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TVirtualKeyboard::TVirtualKeyboard

TVirtualKeyboard ()
TVirtualKeyboard (const TVirtualKeyboard & copy)

Interface Category:

API.

Purpose:

Default constructor. This constructor is protected.
Copy constructor. This constructor is protected.

Calling Context:

Called by the stream-in operators and derived classes.
Called to copy an object.

Parameters:

Takes no parameters.
const TVirtualKeyboard & copy -The object to copy.

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TVirtualKeyboard::Hash

virtual long Hash () const

Interface Category:

API.

Purpose:

Generates a hash value.

Calling Context:

Called to generate a hash value.

Parameters:

Takes no parameters.

Return Value:

The numeric value of the hash.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TVirtualKeyboard::operator=

TVirtualKeyboard & operator =(const TVirtualKeyboard & from)

Interface Category:

API.

Purpose:

Assignment operator.

Calling Context:

Called when an object is assigned to another compatible object.

Parameters:

const TVirtualKeyboard & from -The source object for the assignment.

Return Value:

A non-const reference to the left-hand side object.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TVirtualKeyboard::operator<<=

virtual TStream & operator <<= (TStream & fromWhere)

Interface Category:

API.

Purpose:

Stream-in operator.

Calling Context:

Called to stream in data.

Parameters:

TStream & fromWhere -The stream the object is streamed in from.

Return Value:

Returns a reference to the stream the object streams itself in from.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TVirtualKeyboard::operator>>=

virtual TStream & operator >>=(TStream & toWhere) const

Interface Category:

API.

Purpose:

Stream-out operator.

Calling Context:

Called to stream out data.

Parameters:

TStream & toWhere -The stream the object is streamed out to.

Return Value:

Returns a reference to the stream the object streams itself out to.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TVirtualKeyboard::~TVirtualKeyboard

virtual ~ TVirtualKeyboard ()

Interface Category:

API.

Purpose:

Destructor.

Calling Context:

Called to destroy an object.

Parameters:

Takes no parameters.

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TVirtualKeyboard::GetLocalizableName

virtual void GetLocalizableName (TLocalizableName & name) const

Interface Category:

API.

Purpose:

Provides the human-readable, localizable name for this object.

Calling Context:

Called when clients want to display the human-readable name of a keyboard.

Parameters:

TLocalizableName & name -The name.

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TVirtualKeyboard::CommandText

virtual void CommandText (TVirtualKeyCode :: EVirtualKey key, const TModifierKeys & modifiers, TText & text) const

Interface Category:

API.

Purpose:

Maps from the key and the modifiers to the representative character(s) for the command key using the command keyboard that has been designated for this keyboard. The default calls MapKeyToText. For example, a virtual keyboard could be set up so that the combination of the key, kVirtualA, with the command and option modifiers set results in a TText that can be displayed in a menu as TUnicode::kCommandKey+TUnicode::kOptionKey+TUnicode::kLatinCapitalLetterA.

Calling Context:

Called by menus and other subsystems that need to display a visual representation for command key equivalents.

Parameters:

TVirtualKeyCode :: EVirtualKey key -The key taken from a key event.
const TModifierKeys & modifiers -The modifiers in effect when the key was typed.
TText & text -The text equivalent of the key and modifier combination.

Return Value:

None. The text for display is returned in the text parameter.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TVirtualKeyboard::MapKeyToText

virtual void MapKeyToText (TVirtualKeyCode :: EVirtualKey key, const TModifierKeys & modifiers, TText & text) const

Interface Category:

API.

Purpose:

Defines the primary mapping functionality of virtual keyboards.

Calling Context:

Called by the typing configuration to produce text from a virtual key and modifier combination.

Parameters:

TVirtualKeyCode :: EVirtualKey key -The key taken from a key event.
const TModifierKeys & modifiers -The modifiers in effect when the key was typed.
TText & text -The text that results from the virtual key and modifier combination.

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

This is a pure virtual function and needs to be overridden.

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