Class: TVolumeActionState

Declaration: PlayerControls.h

Taxonomy Categories:

Member Functions:


Interface Category:

API.

Inherits From:

TFloatActionState

Inherited By:

None.

Purpose:

TVolumeActionState is derived from TFloatActionState and is used to control the volume slider.

Instantiation:

Allocate on the heap or the stack.

Deriving Classes:

None.

Concurrency:

Not multithread safe.

Resource Use:

No special requirements.

Other Considerations:

Virtual functions defined in TFloatActionState are overridden in this class.

Member Function: TVolumeActionState::TVolumeActionState

  1. TVolumeActionState (const TPresenterReference & reference, TViewHandle floatControl, bool continuousActions =true, const TSemanticActionType & action =TMediaPresenter :: kVolume)
  2. TVolumeActionState (const TVolumeActionState &)
  3. TVolumeActionState ()

Interface Category:

API.

Purpose:

  1. Normal constructor for setting up a volume action state.
  2. Copy constructor.
  3. Default constructor.

Calling Context:

  1. Called to create a volume slider.
  2. Called to copy an object.
  3. Called by the stream-in operators and derived classes only.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TVolumeActionState::~TVolumeActionState

virtual ~ TVolumeActionState ()

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.

Member Function: TVolumeActionState::operator=

TVolumeActionState & operator =(const TVolumeActionState &)

Interface Category:

API.

Purpose:

Assignment operator.

Calling Context:

Called when an object is assigned to another compatible object.

Parameters:

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: TVolumeActionState::Hash

virtual long Hash () const

Interface Category:

API.

Purpose:

Returns the hash value that uniquely identifies this object within its type. Hash values are used to build dictionaries of objects.

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns the hash value that uniquely identifies this object.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TVolumeActionState::operator==

bool operator ==(const TVolumeActionState &) const

Interface Category:

API.

Purpose:

Tests for equality between the specified TVolumeActionState object and this TVolumeActionState object.

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns true if the two objects are equal; otherwise, returns false.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TVolumeActionState::operator!=

bool operator != (const TVolumeActionState &) const

Interface Category:

API.

Purpose:

Tests for inequality between the specified TVolumeActionState object and this TVolumeActionState object.

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns true if the two objects are different; otherwise, returns false.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TVolumeActionState::operator>>=

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

Interface Category:

API.

Purpose:

Stream-out operator.

Calling Context:

Called to stream out data.

Parameters:

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: TVolumeActionState::operator<<=

virtual TStream & operator <<= (TStream &)

Interface Category:

API.

Purpose:

Stream-in operator.

Calling Context:

Called to stream in data.

Parameters:

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: TVolumeActionState::SetPresenter

virtual void SetPresenter (const TPresenterReference & reference)

Interface Category:

API.

Purpose:

Sets a reference to the media presenter object that defines the semantics for the volume control actions and presentation.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TVolumeActionState::GetFloatValue

virtual double GetFloatValue () const

Interface Category:

API.

Purpose:

Returns the floating-point value that is the primary state of this control state.

Calling Context:

Call this function directly.

Parameters:

Return Value:

Returns this float control state's current floating-point value.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TVolumeActionState::SetFloatValue

virtual void SetFloatValue (double)

Interface Category:

API.

Purpose:

Sets the floating-point value that is the primary state of this control state.

Calling Context:

Call this function directly.

Parameters:

Return Value:

None.

Exceptions:

Throws no exceptions, passes all exceptions through.

Concurrency:

Not multithread safe.

Other Considerations:

None.

Member Function: TVolumeActionState::GetFloatConstraints

virtual void GetFloatConstraints (double & minimum, double & maximum, double & intervalSize) const

Interface Category:

API.

Purpose:

Gets the constraints currently applied to this float control state's value. The first two parameters indicate the range within which this float control state's value must fall. The third parameter indicates the discrete interval by which to constrain this float control state's value. For example, if the interval is 1.0, then the float control state's value is constrained to whole numbers. An interval of 0.0 indicates that there is no interval constraint.

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 declared as a pure virtual function in the base class and must be overridden by TVolumeActionState.
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