ITextOffscreen Class Reference

#include <ITextOffscreen.h>

Inheritance diagram for ITextOffscreen:

Public Member Functions
virtual bool16	CreateOffscreen (IPMUnknown *pShape, IGraphicsContext *gc)=0
virtual bool16	Draw (IPMUnknown *pShape, IGraphicsContext *gc)=0
virtual bool16	IsSupported (const IPMUnknown *pShape) const =0
virtual bool16	Clear (const IPMUnknown *pShape=0)=0
virtual void	Enable (bool16 bOn=kTrue)=0
virtual bool16	IsEnabled () const =0
virtual void	SetLowMemory (bool16 bOn=kTrue)=0
virtual bool16	IsLowMemory () const =0
virtual void	SetTypingMode (bool16 bOn=kTrue)=0
virtual bool16	IsInTypingMode () const =0
virtual bool16	IsInDrawingMode () const =0
virtual bool16	HasPendingInvals () const =0
virtual IPMUnknown *	GetTargetTextFrame () const =0
virtual bool16	Draw (IPMUnknown *pShape, IGraphicsContext *gc, dvaui::drawbot::Drawbot *drawbotP)=0
Public Member Functions inherited from IPMUnknown
virtual IPMUnknown *	QueryInterface (PMIID interfaceID) const =0
virtual void	AddRef () const =0
virtual void	Release () const =0

Detailed Description

ITextOffscreen is a class which is used to quickly process IPendingInvals on the text model. The idea is that when a text frame has focus and the user is typing, we want to draw the text frontmost and quickly update the view without going through the typical OS level invalidation followed by the processing of a paint/update message from the OS.

Member Function Documentation

virtual bool16 ITextOffscreen::Clear ( const IPMUnknown *  pShape = 0 )

pure virtual

Called by the TextEditor and the TextOffscreenObserver if the offscreen needs to be recalculated.

Parameters

pShape

- IN: the text frame (kFrameItemBoss).

Returns

kTrue if this shape is currently supported. If pShape is nil it will clear all sprites.

virtual bool16 ITextOffscreen::CreateOffscreen ( IPMUnknown *  pShape, IGraphicsContext *  gc  )

pure virtual

Initializes the text offscreen for the given text frame (kFrameItemBoss).

Parameters

pShape	- IN: Pointer to the text frame with focus (kFrameItemBoss).
gc	- IN: Pointer to the graphics context (the view/window that we are drawing to).

Returns

kFalse if it was not possible to create the offscreen or if the pShape does not have typing focus. If CreateOffscreen is successful, kTrue is returned. If the textoffscreen has already been initialized with the given pShape, then this method is a no-op and kTrue is returned.

virtual bool16 ITextOffscreen::Draw ( IPMUnknown *  pShape, IGraphicsContext *  gc  )

pure virtual

Draw causes an update to occur for the text frame to the provided graphics context.

Parameters

pShape	- IN: the text frame (kFrameItemBoss).
gc	- IN: Pointer to the graphics context (the view/window that we are drawing to).

Returns

kTrue if the draw occurred successfully, kFalse otherwise.

virtual bool16 ITextOffscreen::Draw ( IPMUnknown *  pShape, IGraphicsContext *  gc, dvaui::drawbot::Drawbot *  drawbotP  )

pure virtual

INTERNAL USE ONLY

Draw causes an update to occur for the text frame to the provided graphics context.

Parameters

pShape	- IN: the text frame (kFrameItemBoss).
gc	- IN: Pointer to the graphics context (the view/window that we are drawing to).
drawbotP	- IN: The destination drawbot to draw to. Used when drawing from the view's DV_Draw.

Returns

kTrue if the draw occurred successfully, kFalse otherwise.

virtual void ITextOffscreen::Enable ( bool16  bOn = kTrue )

pure virtual

Enables/Disables the text offscreen.

Parameters

bOn	- IN: if kTrue, then enable text offscreening, otherwise disable.

virtual IPMUnknown* ITextOffscreen::GetTargetTextFrame ( ) const

pure virtual

Returns

Returns a pointer to the text frame for which this offscreen is setup. Nil if the offscreen is not set up. You should be able to query for the ITextFrameColumn using the returned pointer.

virtual bool16 ITextOffscreen::HasPendingInvals ( ) const

pure virtual

Returns

Returns true if we are typing, this offscreen is active for the frame that has focus and the frame has invals pending.

virtual bool16 ITextOffscreen::IsEnabled ( ) const

pure virtual

Returns

Returns the current Enabled state of the text offscreen.

virtual bool16 ITextOffscreen::IsInDrawingMode ( ) const

pure virtual

Returns

Returns whether it is currently drawing

virtual bool16 ITextOffscreen::IsInTypingMode ( ) const

pure virtual

Returns

Returns the current typing mode state.

virtual bool16 ITextOffscreen::IsLowMemory ( ) const

pure virtual

Returns

Returns the low memory state.

virtual bool16 ITextOffscreen::IsSupported ( const IPMUnknown *  pShape ) const

pure virtual

IsSupported is used to determine if the text offscreen is active for the given pShape.

Parameters

pShape

- IN: the text frame (kFrameItemBoss).

Returns

kTrue if the textoffscreen is active for the given pShape.

virtual void ITextOffscreen::SetLowMemory ( bool16  bOn = kTrue )

pure virtual

Set by the TextOffscreenSprite if it was not able to create a sprite. Low memory mode for sprites typically means that the drawing will be in XOr mode instead of using offscreens.

Parameters

bOn	- IN: kTrue if in low memory mode.

virtual void ITextOffscreen::SetTypingMode ( bool16  bOn = kTrue )

pure virtual

Set the typing mode. Set by the TextEditor on GetFocus/LoseFocus()

Parameters

bOn	- IN: kTrue if we are in typing mode.