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Taxonomy Categories:
Member Functions:
Interface Category:
API.
Inherits From:
MCollectible
Inherited By:
TAbstractDocumentComponentCommandBinding
TToolCommandBinding
Purpose:
Provides an abstract base class for binding commands to targets. Command bindings bind an instance of a command to an instance of a target. Command bindings may be captured for histories, collaboration, etc.
Instantiation:
Allocate on the heap or the stack.
Deriving Classes:
Derive from TCommandBinding to create concrete command binding classes that bind commands to specific types of targets.
Derived classes must override the pure virtual functions: Do, DoBegin, DoIncrement, DoEnd, Undo, Redo, GetUndoType, CanDo, CanUndo, CanRedo, and Commit. These member functions should delegate to the corresponding member function of TCommnandOn<ATarget>, passing the appropriate target.
Concurrency:
Not multithread safe.
Resource Use:
No special requirements.
Invariants:
None.
virtual ~ TCommandBinding ()
Interface Category:
API.
Purpose:
Destructor.
Calling Context:
Called to destroy an object.
Parameters:
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
None.
virtual void Do ()
Interface Category:
API.
Purpose:
Do a command passing the bound target.
Calling Context:
Call this function directly.
Parameters:
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
This function is a pure virtual function and must be overridden by classes deriving from TCommandBinding.
virtual void DoBegin ()
Interface Category:
API.
Purpose:
DoBegin a command passing the bound target.
Calling Context:
Call this function directly.
Parameters:
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
This function is a pure virtual function and must be overridden by classes deriving from TCommandBinding.
virtual void DoIncrement ()
Interface Category:
API.
Purpose:
DoIncrement a command passing the bound target.
Calling Context:
Call this function directly.
Parameters:
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
This function is a pure virtual function and must be overridden by classes deriving from TCommandBinding.
virtual void DoEnd ()
Interface Category:
API.
Purpose:
DoEnd on the command previously begin with a bound target.
Calling Context:
Call this function directly.
Parameters:
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
This function is a pure virtual function and must be overridden by classes deriving from TCommandBinding.
virtual void Undo ()
Interface Category:
API.
Purpose:
Undo a command passing a bound target.
Calling Context:
Call this function directly after a command has been done.
Parameters:
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
This function is a pure virtual function and must be overridden by classes deriving from TCommandBinding.
virtual void Redo ()
Interface Category:
API.
Purpose:
Redo a command on the bound target.
Calling Context:
Call this function directly after a command has been undone.
Parameters:
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
This function is a pure virtual function and must be overridden by classes deriving from TCommandBinding.
virtual TCommonCommand::UndoType GetUndoType() const
Interface Category:
API.
Purpose:
Returns a copy of the undo type of the command. The undo type is immutable
Calling Context:
Call this function directly.
Parameters:
Return Value:
Returns a copy of the undo type of the command.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
This function is a pure virtual function and must be overridden by classes deriving from TCommandBinding.
virtual bool CanDo () const
Interface Category:
API.
Purpose:
Calls CanDo on a command passing the bound target.
Calling Context:
Call this function directly.
Parameters:
Return Value:
Returns true if the bound command returns true.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
This function is a pure virtual function and must be overridden by classes deriving from TCommandBinding.
virtual bool CanUndo () const
Interface Category:
API.
Purpose:
Calls CanUndo on a command passing the bound target.
Calling Context:
Call this function directly.
Parameters:
Return Value:
Returns true if the bound command returns true.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
This function is a pure virtual function and must be overridden by classes deriving from TCommandBinding.
virtual bool CanRedo () const
Interface Category:
API.
Purpose:
Calls CanRedo on a command passing the bound target.
Calling Context:
Call this function directly.
Parameters:
Return Value:
Returns true if the bound command returns true.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
This function is a pure virtual function and must be overridden by classes deriving from TCommandBinding.
virtual void Commit ()
Interface Category:
API.
Purpose:
Commits the command passing the bound target.
Calling Context:
Call this function directly after a command has been, done, undone, redone.
Parameters:
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
This function is a pure virtual function and must be overridden by classes deriving from TCommandBinding.
- TCommandBinding ()
- TCommandBinding (const TCommandBinding &)
Interface Category:
API.
Purpose:
- Default constructor.
- Copy constructor.
Calling Context:
- Called by the stream-in operators only.
- Called to copy an object.
Parameters:
Return Value:
None.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
TCommandBinding is an abstract base class--all the constructors are protected. Do not instantiate this class.
TCommandBinding & operator =(const TCommandBinding &)
Interface Category:
API.
Purpose:
Assignment operator.
Calling Context:
Call this function by using the operator in an assignment statement.
Parameters:
Return Value:
Returns a const reference to the left-hand side object.
Exceptions:
Throws no exceptions, passes all exceptions through.
Concurrency:
Not multithread safe.
Other Considerations:
TCommandBinding is an abstract base class--all the constructors are protected. Do not instantiate this class.
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