BDragger Class Reference

A view that allows the user drag and drop a target view. More...

Inherits BView.

Public Member Functions
	BDragger (BMessage *data)
	Constructs a BDragger object from message data.
	BDragger (BRect frame, BView *target, uint32 resizingMode=B_FOLLOW_NONE, uint32 flags=B_WILL_DRAW)
	Creates a new BDragger and sets its target view.
virtual	~BDragger ()
	Destroys the BDragger object and frees the memory it uses, primarily from the bitmap handle.
virtual void	AllAttached ()
	Similar to AttachedToWindow() but this method is triggered after all child views have already been attached to a window.
virtual void	AllDetached ()
	Similar to AttachedToWindow() but this method is triggered after all child views have already been detached from a window.
virtual status_t	Archive (BMessage *data, bool deep=true) const
	Archives the draggers's relationship to the target view.
virtual void	AttachedToWindow ()
	Puts the BDragger under the control of HideAllDraggers() and ShowAllDraggers().
virtual void	DetachedFromWindow ()
	Removes the BDragger from the control of HideAllDraggers() and ShowAllDraggers().
virtual void	Draw (BRect updateRect)
	Draws the dragger handle.
virtual void	FrameMoved (BPoint newPosition)
	Hook method called when the view is moved.
virtual void	FrameResized (float newWidth, float newHeight)
	Hook method called when the view is resized.
virtual void	GetPreferredSize (float *_width, float *_height)
	Fill out the preferred width and height of the view into the _width and _height parameters.
virtual status_t	GetSupportedSuites (BMessage *data)
virtual void	MakeFocus (bool focus=true)
	Makes the view the current focus view of the window or gives up being the window's focus view.
virtual void	MessageReceived (BMessage *message)
	Receives messages that control the visibility of the dragger handle.
virtual void	MouseDown (BPoint where)
	Hook method that is called when a mouse button is pressed over the dragger.
virtual void	MouseMoved (BPoint where, uint32 transit, const BMessage *dragMessage)
	Hook method called when the mouse is moved.
virtual void	MouseUp (BPoint where)
	Hook method called when a mouse button is released.
virtual status_t	Perform (perform_code code, void *data)
	Perform some action. (Internal Method)
virtual void	ResizeToPreferred ()
	Resizes the view to its preferred size keeping the position of the left top corner constant.
virtual BHandler *	ResolveSpecifier (BMessage *message, int32 index, BMessage *specifier, int32 form, const char *property)
Public Member Functions inherited from BView
	BView (BMessage *archive)
	Archive constructor.
	BView (BRect frame, const char *name, uint32 resizingMode, uint32 flags)
	Standard constructor.
	BView (const char *name, uint32 flags, BLayout *layout=NULL)
	Layout constructor.
virtual	~BView ()
	Destructor method.
BRect	Bounds () const
	Returns the view's frame rectangle in the view's coordinate system.
void	Flush () const
	Flushes the attached window's connection to App Server.
BRect	Frame () const
	Returns the view's frame rectangle in the parent's coordinate system.
virtual void	GetPreferredSize (float *_width, float *_height)
	Fill out the preferred width and height of the view into the _width and _height parameters.
virtual status_t	GetSupportedSuites (BMessage *data)
virtual void	Hide ()
	Hides the view without removing it from the view hierarchy.
bool	IsFocus () const
	Returns whether or not the view is the window's current focus view.
bool	IsHidden () const
	Returns whether or not the view is hidden.
bool	IsHidden (const BView *looking_from) const
	Returns whether or not the view is hidden from the perspective of lookingFrom.
bool	IsPrinting () const
	Returns whether or not the view is drawing to a printer.
BPoint	LeftTop () const
	Returns the left top corner point.
virtual status_t	Perform (perform_code code, void *data)
	Perform some action. (Internal Method)
virtual void	ResizeToPreferred ()
	Resizes the view to its preferred size keeping the position of the left top corner constant.
uint32	ResizingMode () const
	Returns the resizing mode flags mask set in the constructor or by SetResizingMode().
virtual BHandler *	ResolveSpecifier (BMessage *message, int32 index, BMessage *specifier, int32 form, const char *property)
virtual void	SetResizingMode (uint32 mode)
	Sets the resizing mode of the view according to the mode mask.
void	SetViewCursor (const BCursor *cursor, bool sync=true)
	Assigns cursor to the view.
virtual void	Show ()
	Shows the view making it visible.
void	Sync () const
	Synchronizes the attached window's connection to App Server.
BWindow *	Window () const
	Returns the window the view is attached to.
void	AddChild (BView *child, BView *before=NULL)
	Adds child to the view hierarchy immediately before before.
bool	AddChild (BLayoutItem *child)
	Add the child layout item to the view hierarchy.
bool	RemoveChild (BView *child)
	Removes child from the view hierarchy.
int32	CountChildren () const
	Returns the number of child views that this view has.
BView *	ChildAt (int32 index) const
	Returns a pointer to the child view found at index.
BView *	NextSibling () const
	Returns a pointer to the next sibling view.
BView *	PreviousSibling () const
	Returns a pointer to the previous sibling view.
bool	RemoveSelf ()
	Removes the view and all child views from the view hierarchy.
BView *	FindView (const char *name) const
	Returns the view in the view hierarchy with the specified name.
BView *	Parent () const
	Returns a pointer to the view's parent.
void	ConvertToScreen (BPoint *point) const
	Convert point to the screen's coordinate system in place.
BPoint	ConvertToScreen (BPoint point) const
	Returns point converted to the screen's coordinate system.
void	ConvertFromScreen (BPoint *point) const
	Convert point from the screen's coordinate system to the view's coordinate system in place.
BPoint	ConvertFromScreen (BPoint point) const
	Returns point converted from the screen's coordinate system to the view's coordinate system.
void	ConvertToScreen (BRect *rect) const
	Convert rect to the screen's coordinate system in place.
BRect	ConvertToScreen (BRect rect) const
	Returns rect converted to the screen's coordinate system.
void	ConvertFromScreen (BRect *rect) const
	Convert rect from the screen's coordinate system to the view's coordinate system in place.
BRect	ConvertFromScreen (BRect rect) const
	Returns rect converted from the screen's coordinate system to the view's coordinate system.
void	ConvertToParent (BPoint *point) const
	Convert point to the parent's coordinate system in place.
BPoint	ConvertToParent (BPoint point) const
	Returns point converted to the parent's coordinate system.
void	ConvertFromParent (BPoint *point) const
	Convert point from the parent's coordinate system to the view's coordinate system in place.
BPoint	ConvertFromParent (BPoint point) const
	Returns point converted from the parent's coordinate system to the view's coordinate system.
void	ConvertToParent (BRect *rect) const
	Convert rect to the parent's coordinate system in place.
BRect	ConvertToParent (BRect rect) const
	Returns rect converted to the parent's coordinate system.
void	ConvertFromParent (BRect *rect) const
	Convert rect from the parent's coordinate system to the view's coordinate system in place.
BRect	ConvertFromParent (BRect rect) const
	Returns rect converted from the parent's coordinate system to the view's coordinate system.
virtual void	SetFlags (uint32 flags)
	Sets the view flags to the flags mask.
uint32	Flags () const
	Return the view flags set in the constructor or by SetFlags().
void	GetClippingRegion (BRegion *region) const
	Fill out region with the view's clipping region.
virtual void	ConstrainClippingRegion (BRegion *region)
	Set the clipping region the region restricting the area that the view can draw in.
void	ClipToPicture (BPicture *picture, BPoint where=B_ORIGIN, bool sync=true)
	Intersects the current clipping region of the view with the pixels of picture.
void	ClipToInversePicture (BPicture *picture, BPoint where=B_ORIGIN, bool sync=true)
	Intersects the current clipping region of the view with the pixels outside of picture.
void	ClipToRect (BRect rect)
	Intersects the current clipping region of the view with the pixels of rect.
void	ClipToInverseRect (BRect rect)
	Intersects the current clipping region of the view with the pixels outside of rect.
void	ClipToShape (BShape *shape)
	Intersects the current clipping region of the view with the pixels of shape.
void	ClipToInverseShape (BShape *shape)
	Intersects the current clipping region of the view with the pixels outside of shape.
virtual void	SetDrawingMode (drawing_mode mode)
	Sets the drawing mode of the view.
drawing_mode	DrawingMode () const
	Return the current drawing_mode.
void	SetBlendingMode (source_alpha srcAlpha, alpha_function alphaFunc)
	Set the blending mode which controls how transparency is used.
void	GetBlendingMode (source_alpha *srcAlpha, alpha_function *alphaFunc) const
	Fill out srcAlpha and alphaFunc with the alpha mode and alpha function of the view.
virtual void	SetPenSize (float size)
	Set the pen size to size.
float	PenSize () const
	Return the current pen size.
bool	HasDefaultColors () const
	Tests if the view has any colors set.
bool	HasSystemColors () const
	Tests if the view is using system "panel" colors. B_PANEL_BACKGROUND_COLOR for ViewUIColor() B_PANEL_BACKGROUND_COLOR for LowUIColor() B_PANEL_TEXT_COLOR for HighUIColor()
void	AdoptParentColors ()
	Attempts to use the colors of any parent view. Will adopt view, low, and high colors. Should be called in AttachedToWindow() or AllAttached().
void	AdoptSystemColors ()
	Instructs view to use standard system "panel" colors. B_PANEL_BACKGROUND_COLOR for ViewUIColor() B_PANEL_BACKGROUND_COLOR for LowUIColor() B_PANEL_TEXT_COLOR for HighUIColor()
void	AdoptViewColors (BView *view)
	Attempts to use the colors of a given view. Will adopt view, low, and high colors.
virtual void	SetViewColor (rgb_color color)
	Set the view color of the view.
void	SetViewColor (uchar red, uchar green, uchar blue, uchar alpha=255)
	Set the view color of the view.
rgb_color	ViewColor () const
	Return the current view color.
void	SetViewUIColor (color_which which, float tint=B_NO_TINT)
	Set the view color of the view to a system constant. The color will update live with user changes.
color_which	ViewUIColor (float *tint=NULL) const
	Return the current view color constant being used.
virtual void	SetHighColor (rgb_color color)
	Set the high color of the view.
void	SetHighColor (uchar red, uchar green, uchar blue, uchar alpha=255)
	Set the high color of the view.
rgb_color	HighColor () const
	Return the current high color.
void	SetHighUIColor (color_which which, float tint=B_NO_TINT)
	Set the high color of the view to a system constant. The color will update live with user changes.
color_which	HighUIColor (float *tint=NULL) const
	Return the current high color constant being used.
virtual void	SetLowColor (rgb_color color)
	Set the low color of the view.
void	SetLowColor (uchar red, uchar green, uchar blue, uchar alpha=255)
	Set the low color of the view.
rgb_color	LowColor () const
	Return the current low color.
void	SetLowUIColor (color_which which, float tint=B_NO_TINT)
	Set the low color of the view to a system constant. The color will update live with user changes.
color_which	LowUIColor (float *tint=NULL) const
	Return the current low color constant being used.
void	SetLineMode (cap_mode lineCap, join_mode lineJoin, float miterLimit=B_DEFAULT_MITER_LIMIT)
	Set line mode to use PostScript-style line cap and join modes.
join_mode	LineJoinMode () const
	Returns the current line join mode.
cap_mode	LineCapMode () const
	Returns the current line cap mode.
float	LineMiterLimit () const
	Returns the miter limit used for B_MITER_JOIN join mode.
void	SetFillRule (int32 rule)
	Sets the fill rule for the view.
int32	FillRule () const
	Return the current fill mode.
void	SetOrigin (BPoint where)
	Sets the origin in the view's coordinate system.
void	SetOrigin (float x, float y)
	Sets the origin in the view's coordinate system.
BPoint	Origin () const
	Returns the origin point in the view's coordinate system.
void	SetTransform (BAffineTransform transform)
	Sets a BAffineTransform to transform the coordinate system.
BAffineTransform	Transform () const
	Returns the current BAffineTransform that is applied to the coordinate system.
void	TranslateBy (double x, double y)
	Translate the current view by coordinates.
void	ScaleBy (double x, double y)
	Scale the current view by factors x and y.
void	RotateBy (double angleRadians)
	Rotate the current view by angleRadians.
BAffineTransform	TransformTo (coordinate_space basis) const
	Return the BAffineTransform to convert from the current drawing space to basis.
void	PushState ()
	Saves the drawing state to the stack.
void	PopState ()
	Restores the drawing state from the stack.
void	MovePenTo (BPoint pt)
	Move the pen to point in the view's coordinate system.
void	MovePenTo (float x, float y)
	Move the pen to the point specified by x and y in the view's coordinate system.
void	MovePenBy (float x, float y)
	Move the pen by x pixels horizontally and y pixels vertically.
BPoint	PenLocation () const
	Return the current pen location as a BPoint object.
virtual void	SetFont (const BFont *font, uint32 mask=B_FONT_ALL)
	Set the font of the view.
void	GetFont (BFont *font) const
	Fill out font with the font set to the view.
void	TruncateString (BString *in_out, uint32 mode, float width) const
	Truncate string with truncation mode mode so that it is no wider than width set in the view's font.
float	StringWidth (const char *string) const
	Return the width of string set in the font of the view.
float	StringWidth (const char *string, int32 length) const
	Return the width of string set in the font of the view up to length characters.
void	GetStringWidths (char *stringArray[], int32 lengthArray[], int32 numStrings, float widthArray[]) const
	Fill out widths of the strings in stringArray set in the font of the view into widthArray.
void	SetFontSize (float size)
	Set the size of the view's font to size.
void	ForceFontAliasing (bool enable)
	Turn anti-aliasing on and off when printing.
void	GetFontHeight (font_height *height) const
	Fill out the font_height struct with the view font.
void	SetScale (float scale) const
	Sets the scale of the coordinate system the view uses for drawing.
float	Scale () const
	Return the current drawing scale.
void	SetViewBitmap (const BBitmap *bitmap, BRect srcRect, BRect dstRect, uint32 followFlags=B_FOLLOW_LEFT_TOP, uint32 options=B_TILE_BITMAP)
	Sets the background bitmap of the view.
void	SetViewBitmap (const BBitmap *bitmap, uint32 followFlags=B_FOLLOW_LEFT_TOP, uint32 options=B_TILE_BITMAP)
	Sets the background bitmap of the view.
void	ClearViewBitmap ()
	Clears the background bitmap of the view if it has one.
status_t	SetViewOverlay (const BBitmap *overlay, BRect srcRect, BRect dstRect, rgb_color *colorKey, uint32 followFlags=B_FOLLOW_LEFT_TOP, uint32 options=0)
	Sets the overlay bitmap of the view.
status_t	SetViewOverlay (const BBitmap *overlay, rgb_color *colorKey, uint32 followFlags=B_FOLLOW_LEFT_TOP, uint32 options=0)
	Sets the overlay bitmap of the view.
void	ClearViewOverlay ()
	Clears the overlay bitmap of the view if it has one.
void	StrokeLine (BPoint toPoint, ::pattern pattern=B_SOLID_HIGH)
	Stroke a line from the current pen location to the point toPoint.
void	StrokeLine (BPoint start, BPoint end, ::pattern pattern=B_SOLID_HIGH)
	Stroke a line from point start to point end.
void	BeginLineArray (int32 count)
	Begin a line array of up to count lines.
void	AddLine (BPoint start, BPoint end, rgb_color color)
	Add a line to the line array drawn from start to end.
void	EndLineArray ()
	End the line array drawing the lines.
void	StrokePolygon (const BPolygon *polygon, bool closed=true, ::pattern pattern=B_SOLID_HIGH)
	Stroke a polygon shape.
void	StrokePolygon (const BPoint *pointArray, int32 numPoints, bool closed=true, ::pattern pattern=B_SOLID_HIGH)
	Stroke a polygon shape made up of points specified by pointArray.
void	StrokePolygon (const BPoint *pointArray, int32 numPoints, BRect bounds, bool closed=true, ::pattern pattern=B_SOLID_HIGH)
	Stroke a polygon shape made up of points specified by pointArray inscribed by bounds.
void	FillPolygon (const BPolygon *polygon, ::pattern pattern=B_SOLID_HIGH)
	Fill a polygon shape.
void	FillPolygon (const BPoint *pointArray, int32 numPoints, ::pattern pattern=B_SOLID_HIGH)
	Fill a polygon shape made up of points specified by pointArray.
void	FillPolygon (const BPoint *pointArray, int32 numPoints, BRect bounds, ::pattern pattern=B_SOLID_HIGH)
	Fill a polygon shape made up of points specified by pointArray inscribed by bounds.
void	FillPolygon (const BPolygon *polygon, const BGradient &gradient)
	Fill a polygon shape with the specified gradient pattern.
void	FillPolygon (const BPoint *pointArray, int32 numPoints, const BGradient &gradient)
	Fill a polygon shape made up of points specified by pointArray with the specified gradient pattern.
void	FillPolygon (const BPoint *pointArray, int32 numPoints, BRect bounds, const BGradient &gradient)
	Fill a polygon shape made up of points specified by pointArray inscribed by bounds with the specified gradient pattern.
void	StrokeTriangle (BPoint point1, BPoint point2, BPoint point3, BRect bounds, ::pattern pattern=B_SOLID_HIGH)
	Stroke the triangle specified by points point1, point2, and point3 and enclosed by bounds.
void	StrokeTriangle (BPoint point1, BPoint point2, BPoint point3, ::pattern pattern=B_SOLID_HIGH)
	Stroke the triangle specified by points point1, point2, and point3.
void	FillTriangle (BPoint point1, BPoint point2, BPoint point3, ::pattern pattern=B_SOLID_HIGH)
	Fill the triangle specified by points point1, point2, and point3.
void	FillTriangle (BPoint point1, BPoint point2, BPoint point3, BRect bounds, ::pattern pattern=B_SOLID_HIGH)
	Fill the triangle specified by points point1, point2, and point3 and enclosed by bounds.
void	FillTriangle (BPoint point1, BPoint point2, BPoint point3, const BGradient &gradient)
	Fill the triangle specified by points point1, point2, and point3 with the specified gradient pattern.
void	FillTriangle (BPoint point1, BPoint point2, BPoint point3, BRect bounds, const BGradient &gradient)
	Fill the triangle specified by points point1, point2, and point3 and enclosed by bounds with the specified gradient pattern.
void	StrokeRect (BRect rect, ::pattern pattern=B_SOLID_HIGH)
	Stroke the rectangle specified by rect.
void	FillRect (BRect rect, ::pattern pattern=B_SOLID_HIGH)
	Fill the rectangle specified by rect.
void	FillRect (BRect rect, const BGradient &gradient)
	Fill the rectangle specified by rect with the specified gradient pattern.
void	FillRegion (BRegion *rectegion, ::pattern pattern=B_SOLID_HIGH)
	Fill region.
void	FillRegion (BRegion *rectegion, const BGradient &gradient)
	Fill region with the specified gradient pattern.
void	InvertRect (BRect rect)
	Inverts the colors within rect.
void	StrokeRoundRect (BRect rect, float xRadius, float yRadius, ::pattern pattern=B_SOLID_HIGH)
	Stroke the rounded rectangle with horizontal radius xRadius and vertical radius yRadius.
void	FillRoundRect (BRect rect, float xRadius, float yRadius, ::pattern pattern=B_SOLID_HIGH)
	Fill the rounded rectangle with horizontal radius xRadius and vertical radius yRadius.
void	FillRoundRect (BRect rect, float xRadius, float yRadius, const BGradient &gradient)
	Fill the rounded rectangle with horizontal radius xRadius and vertical radius yRadius with the specified gradient pattern.
void	StrokeEllipse (BPoint center, float xRadius, float yRadius, ::pattern pattern=B_SOLID_HIGH)
	Stroke the outline of an ellipse starting at center with a horizontal radius of xRadius and a vertical radius of yRadius.
void	StrokeEllipse (BRect rect, ::pattern pattern=B_SOLID_HIGH)
	Stroke the outline of an ellipse inscribed within rect.
void	FillEllipse (BPoint center, float xRadius, float yRadius, ::pattern pattern=B_SOLID_HIGH)
	Fill an ellipse starting at center with a horizontal radius of xRadius and a vertical radius of yRadius.
void	FillEllipse (BRect rect, ::pattern pattern=B_SOLID_HIGH)
	Fill an ellipse inscribed within rect.
void	FillEllipse (BPoint center, float xRadius, float yRadius, const BGradient &gradient)
	Fill an ellipse with the specified gradient pattern starting at center with a horizontal radius of xRadius and a vertical radius of yRadius.
void	FillEllipse (BRect rect, const BGradient &gradient)
	Fill an ellipse with the specified gradient pattern inscribed within rect.
void	StrokeArc (BPoint center, float xRadius, float yRadius, float startAngle, float arcAngle, ::pattern pattern=B_SOLID_HIGH)
	Stroke the outline of an arc starting at center with a horizontal radius of xRadius and a vertical radius of yRadius starting at startAngle and drawing arcAngle degrees.
void	StrokeArc (BRect rect, float startAngle, float arcAngle, ::pattern pattern=B_SOLID_HIGH)
	Stroke the outline of an arc inscribed within rect starting at startAngle and drawing arcAngle degrees.
void	FillArc (BPoint center, float xRadius, float yRadius, float startAngle, float arcAngle, ::pattern pattern=B_SOLID_HIGH)
	Fill an arc starting at center with a horizontal radius of xRadius and a vertical radius of yRadius starting at startAngle and drawing arcAngle degrees.
void	FillArc (BRect rect, float startAngle, float arcAngle, ::pattern pattern=B_SOLID_HIGH)
	Fill an arc inscribed within rect starting at startAngle and drawing arcAngle degrees.
void	FillArc (BPoint center, float xRadius, float yRadius, float startAngle, float arcAngle, const BGradient &gradient)
	Fill an arc with the specified gradient pattern starting at center with a horizontal radius of xRadius and a vertical radius of yRadius starting at startAngle and drawing arcAngle degrees.
void	FillArc (BRect rect, float startAngle, float arcAngle, const BGradient &gradient)
	Fill an arc with the specified gradient pattern inscribed within rect starting at startAngle and drawing arcAngle degrees.
void	StrokeBezier (BPoint *controlPoints, ::pattern pattern=B_SOLID_HIGH)
	Stroke a bezier curve.
void	FillBezier (BPoint *controlPoints, ::pattern pattern=B_SOLID_HIGH)
	Fill a bezier curve.
void	FillBezier (BPoint *controlPoints, const BGradient &gradient)
	Fill a bezier curve.
void	StrokeShape (BShape *shape, ::pattern pattern=B_SOLID_HIGH)
	Stroke shape.
void	FillShape (BShape *shape, ::pattern pattern=B_SOLID_HIGH)
	Fill shape.
void	FillShape (BShape *shape, const BGradient &gradient)
	Fill shape with the specified gradient pattern.
void	CopyBits (BRect src, BRect dst)
	Copy the bits from the src rectangle to the dst rectangle in the view's coordinate system.
void	DrawBitmapAsync (const BBitmap *aBitmap, BRect bitmapRect, BRect viewRect, uint32 options)
	Draws bitmap on the view within viewRect asynchronously. bitmap portion is scaled to fit viewRect.
void	DrawBitmapAsync (const BBitmap *aBitmap, BRect bitmapRect, BRect viewRect)
	Draws bitmap on the view within viewRect asynchronously. bitmap portion is scaled to fit viewRect.
void	DrawBitmapAsync (const BBitmap *aBitmap, BRect viewRect)
	Draws bitmap on the view within viewRect asynchronously. bitmap is scaled to fit viewRect.
void	DrawBitmapAsync (const BBitmap *aBitmap, BPoint where)
	Draws bitmap on the view offset by where asynchronously.
void	DrawBitmapAsync (const BBitmap *aBitmap)
	Draws bitmap on the view asynchronously.
void	DrawBitmap (const BBitmap *aBitmap, BRect bitmapRect, BRect viewRect, uint32 options)
	Draws bitmap on the view within viewRect. bitmap portion is scaled to fit viewRect.
void	DrawBitmap (const BBitmap *aBitmap, BRect bitmapRect, BRect viewRect)
	Draws bitmap on the view within viewRect. bitmap portion is scaled to fit viewRect.
void	DrawBitmap (const BBitmap *aBitmap, BRect viewRect)
	Draws bitmap on the view within viewRect. bitmap is scaled to fit viewRect.
void	DrawBitmap (const BBitmap *aBitmap, BPoint where)
	Draws bitmap on the view offset by where.
void	DrawBitmap (const BBitmap *aBitmap)
	Draws bitmap on the view.
void	DrawTiledBitmapAsync (const BBitmap *aBitmap, BRect viewRect, BPoint phase=B_ORIGIN)
	Draws bitmap on the view within viewRect asynchronously. If bitmap is smaller, it is cloned to fill remaining space in viewRect.
void	DrawTiledBitmap (const BBitmap *aBitmap, BRect viewRect, BPoint phase=B_ORIGIN)
	Draws bitmap on the view within viewRect. If bitmap is smaller, it is cloned to fill remaining space in viewRect.
void	DrawChar (char aChar)
	Draws character c onto to the view at the current pen position.
void	DrawChar (char aChar, BPoint location)
	Draws character c at the specified location in the view.
void	DrawString (const char *string, escapement_delta *delta=NULL)
	Draw string onto the view at the current pen position.
void	DrawString (const char *string, BPoint location, escapement_delta *delta=NULL)
	Draw string onto the view at the specified location in the view.
void	DrawString (const char *string, int32 length, escapement_delta *delta=NULL)
	Draw string up to length characters onto the view at the current pen position.
void	DrawString (const char *string, int32 length, BPoint location, escapement_delta *delta=0L)
	Draw string up to length characters onto the view at the specified location in the view.
void	DrawString (const char *string, const BPoint *locations, int32 locationCount)
	Draw string locationCount times at the specified locations.
void	DrawString (const char *string, int32 length, const BPoint *locations, int32 locationCount)
	Draw string up to length characters locationCount times at the specified locations.
void	Invalidate (BRect invalRect)
	Sends a message to App Server to redraw the portion of the view specified by invalRect.
void	Invalidate (const BRegion *invalRegion)
	Sends a message to App Server to redraw the portion of the view specified by region.
void	Invalidate ()
	Sends a message to App Server to redraw the view.
void	DelayedInvalidate (bigtime_t delay)
	Sends a message to App Server to redraw the entire view after a certain, minimum, delay. Repeated calls to this method may be merged, but the view is guaranteed to be redrawn after the delay given in the first call of this method.
void	DelayedInvalidate (bigtime_t delay, BRect invalRect)
	Sends a message to App Server to redraw the portion of the view specified by invalRect after a certain, minimum, delay. Repeated calls to this method may be merged, but the invalidated rect is guaranteed to be redrawn after the minimum delay given by the first call of this method.
void	SetDiskMode (char *filename, long offset)
	Unimplemented.
void	BeginPicture (BPicture *a_picture)
	Begins sending drawing instructions to picture.
void	AppendToPicture (BPicture *a_picture)
	Appends drawing instructions to picture without clearing it first.
BPicture *	EndPicture ()
	Ends the drawing instruction recording session and returns the BPicture object passed to BeginPicture() or AppendToPicture().
void	DrawPicture (const BPicture *a_picture)
	Draws the picture at the view's current pen position.
void	DrawPicture (const BPicture *a_picture, BPoint where)
	Draws the picture at the location in the view specified by where.
void	DrawPicture (const char *filename, long offset, BPoint where)
	Draws the picture from the file specified by filename offset by offset bytes at the location in the view specified by where.
void	DrawPictureAsync (const BPicture *a_picture)
	Draws the picture at the view's current pen position.
void	DrawPictureAsync (const BPicture *a_picture, BPoint where)
	Draws the picture at the location in the view specified by where.
void	DrawPictureAsync (const char *filename, long offset, BPoint where)
	Draws the picture from the file specified by filename offset by offset bytes at the location in the view specified by where.
void	BeginLayer (uint8 opacity)
	Begins a drawing layer.
void	EndLayer ()
	Finish a layer and blend it in with the view.
void	MoveBy (float dh, float dv)
	Moves the view deltaX pixels horizontally and deltaY pixels vertically in the parent view's coordinate system.
void	MoveTo (BPoint where)
	Move the view to the location specified by where in the parent view's coordinate system.
void	MoveTo (float x, float y)
	Move the view to the coordinates specified by x in the horizontal dimension and y in the vertical dimension in the parent view's coordinate system.
void	ResizeBy (float dh, float dv)
	Resize the view by deltaWidth horizontally and deltaHeight vertically without moving the top left corner of the view.
void	ResizeTo (float width, float height)
	Resize the view to the specified width and height.
void	ResizeTo (BSize size)
	Resize the view to the dimension specified by size.
virtual status_t	AllUnarchived (const BMessage *archive)
	Hook method called when all views have been unarchived.
virtual status_t	AllArchived (BMessage *archive) const
	Hook method called when all views have been archived.
virtual void	WindowActivated (bool active)
	Hook method called when the attached window is activated or deactivated.
virtual void	KeyDown (const char *bytes, int32 numBytes)
	Hook method called when a keyboard key is pressed.
virtual void	KeyUp (const char *bytes, int32 numBytes)
	Hook method called when a keyboard key is released.
virtual void	Pulse ()
	Hook method called when the view receives a B_PULSE message.
virtual void	TargetedByScrollView (BScrollView *scrollView)
	Hook method called when the view becomes the target of scrollView.
virtual void	DrawAfterChildren (BRect updateRect)
	Perform any drawing that needs to be done after child view have already been drawn.
void	BeginRectTracking (BRect startRect, uint32 style=B_TRACK_WHOLE_RECT)
	Displays an outline rectangle on the view and initiates tracking.
void	EndRectTracking ()
	Ends tracking removing the outline rectangle from the view.
void	GetMouse (BPoint *location, uint32 *buttons, bool checkMessageQueue=true)
	Fills out the cursor location and the current state of the mouse buttons.
void	DragMessage (BMessage *message, BRect dragRect, BHandler *replyTo=NULL)
	Initiates a drag-and-drop session.
void	DragMessage (BMessage *message, BBitmap *bitmap, BPoint offset, BHandler *replyTo=NULL)
	Initiates a drag-and-drop session of an image.
void	DragMessage (BMessage *message, BBitmap *bitmap, drawing_mode dragMode, BPoint offset, BHandler *replyTo=NULL)
	Initiates a drag-and-drop session of an image with drawing_mode set by dragMode.
status_t	SetEventMask (uint32 mask, uint32 options=0)
	Sets whether or not the view can accept mouse and keyboard events when not in focus.
uint32	EventMask ()
	Returns the current event mask.
status_t	SetMouseEventMask (uint32 mask, uint32 options=0)
	Sets whether or not the view can accept mouse and keyboard events when not in focus from within MouseDown() until the following MouseUp() event.
void	ScrollBy (float dh, float dv)
	Scroll the view by deltaX horizontally and deltaY vertically.
void	ScrollTo (float x, float y)
	Scroll the view to the point specified by coordinates.
virtual void	ScrollTo (BPoint where)
	Scroll the view to the point specified by where.
BScrollBar *	ScrollBar (orientation direction) const
	Returns the BScrollBar object that has the BView set as its target.
virtual BSize	MinSize ()
	Return the minimum size of the view.
virtual BSize	MaxSize ()
	Return the maximum size of the view.
virtual BSize	PreferredSize ()
	Return the preferred size of the view.
virtual BAlignment	LayoutAlignment ()
	Return the current BAlignemnt of the view.
void	SetExplicitMinSize (BSize size)
	Set this view's min size, to be used by MinSize().
void	SetExplicitMaxSize (BSize size)
	Set this view's max size, to be used by MaxSize().
void	SetExplicitPreferredSize (BSize size)
	Set this view's preferred size, to be used by PreferredSize().
void	SetExplicitSize (BSize size)
	Set this view's size.
void	SetExplicitAlignment (BAlignment alignment)
	Set this view's alignment, to be used by Alignment().
BSize	ExplicitMinSize () const
	Returns the explicit minimum size.
BSize	ExplicitMaxSize () const
	Returns the explicit maximum size.
BSize	ExplicitPreferredSize () const
	Returns the explicit preferred size.
BAlignment	ExplicitAlignment () const
	Returns the explicit alignment size.
virtual bool	HasHeightForWidth ()
	Returns whether the layout of the view can calculate a height for a given width.
virtual void	GetHeightForWidth (float width, float *min, float *max, float *preferred)
	Returns the min, max and preferred height for a given width.
void	InvalidateLayout (bool descendants=false)
	Invalidate layout.
virtual void	SetLayout (BLayout *layout)
	Sets the layout of the view.
BLayout *	GetLayout () const
	Get the layout of the view.
void	EnableLayoutInvalidation ()
	Enable layout invalidation.
void	DisableLayoutInvalidation ()
	Disable layout invalidation.
bool	IsLayoutInvalidationDisabled ()
	Returns whether or not layout invalidation is disabled.
bool	IsLayoutValid () const
	Returns whether or not the layout is valid.
void	ResetLayoutInvalidation ()
	Service call for BView derived classes re-enabling InvalidateLayout() notifications.
BLayoutContext *	LayoutContext () const
	Returns the BLayoutContext for this View.
void	Layout (bool force)
	Layout the view.
void	Relayout ()
	Relayout the view.
void	SetToolTip (const char *text)
	Set the tool tip of the view to text.
void	SetToolTip (BToolTip *tip)
	Set the tool tip of the view to the tip object.
BToolTip *	ToolTip () const
	Return the tool tip set to the view or NULL if not set.
void	ShowToolTip (BToolTip *tip=NULL)
	Show the tool tip at the current mouse position.
void	HideToolTip ()
	Hide the view's tool tip.
Public Member Functions inherited from BHandler
	BHandler (const char *name=NULL)
	Construct a new handler with a name.
virtual	~BHandler ()
	Free the filters of this handler, as well as the list of observers.
virtual status_t	Perform (perform_code d, void *arg)
	Perform some action (Internal method defined for binary compatibility purposes).
	BHandler (BMessage *data)
	Construct a handler from an archived message.
BLooper *	Looper () const
	Return a pointer to the looper that this handler is associated with.
void	SetName (const char *name)
	Set or change the name of this handler.
const char *	Name () const
	Return the name of this handler.
virtual void	SetNextHandler (BHandler *handler)
	Set the next handler in the chain that the message is passed on to if this handler cannot process it.
BHandler *	NextHandler () const
	Return the next hander in the chain to which the message is passed on.
virtual void	AddFilter (BMessageFilter *filter)
	Add filter as a prerequisite to this handler.
virtual bool	RemoveFilter (BMessageFilter *filter)
	Remove filter from the filter list.
virtual void	SetFilterList (BList *filters)
	Set the internal list of filters to filters.
BList *	FilterList ()
	Return a pointer to the list of filters.
bool	LockLooper ()
	Lock the looper associated with this handler.
status_t	LockLooperWithTimeout (bigtime_t timeout)
	Lock the looper associated with this handler, with a time out value.
void	UnlockLooper ()
	Unlock the looper.
status_t	StartWatching (BMessenger target, uint32 what)
	Subscribe this handler to watch a specific state change of a target.
status_t	StartWatchingAll (BMessenger target)
	Subscribe this handler to watch a target for all events.
status_t	StopWatching (BMessenger target, uint32 what)
	Unsubscribe this handler from watching a specific state.
status_t	StopWatchingAll (BMessenger target)
	Unsubscribe this handler from watching all states.
status_t	StartWatching (BHandler *observer, uint32 what)
	Subscribe an observer for a specific state change of this handler.
status_t	StartWatchingAll (BHandler *observer)
	Subscribe an observer for a all state changes.
status_t	StopWatching (BHandler *observer, uint32 what)
	Unsubscribe an observer from watching a specific state.
status_t	StopWatchingAll (BHandler *observer)
	Unsubscribe an observer from watching all states.
virtual void	SendNotices (uint32 what, const BMessage *notice=NULL)
	Emit a state change to the observers.
bool	IsWatched () const
	Check if there are any observers watching this handler.
Public Member Functions inherited from BArchivable
	BArchivable ()
	Constructor. Does nothing.
	BArchivable (BMessage *from)
	Constructor. Does important behind-the-scenes work in the unarchiving process.
virtual	~BArchivable ()
	Destructor. Does nothing.
virtual status_t	AllArchived (BMessage *archive) const
	Method relating to the use of BArchiver.
virtual status_t	AllUnarchived (const BMessage *archive)
	Method relating to the use of BUnarchiver.
virtual status_t	Archive (BMessage *into, bool deep=true) const
	Archive the object into a BMessage.
virtual status_t	Perform (perform_code d, void *arg)
	Perform some action (Internal method defined for binary compatibility purposes).

Static Public Member Functions
static bool	AreDraggersDrawn ()
	Returns whether or not draggers are currently drawn.
static status_t	HideAllDraggers ()
	Hides all BDragger objects so that they're not visible on screen.
static BArchivable *	Instantiate (BMessage *data)
	Creates a new BDragger object from the BMessage constructor.
static status_t	ShowAllDraggers ()
	Causes all BDragger objects to draw their handles.
Static Public Member Functions inherited from BView
static BArchivable *	Instantiate (BMessage *archive)
	Creates a new BView object from the data message.
Static Public Member Functions inherited from BHandler
static BArchivable *	Instantiate (BMessage *data)
	Static method to instantiate a handler from an archived message.
Static Public Member Functions inherited from BArchivable
static BArchivable *	Instantiate (BMessage *archive)
	Static member to restore objects from messages.

Additional Inherited Members
Protected Member Functions inherited from BView
virtual void	LayoutInvalidated (bool descendants=false)
	Hook method called when the layout is invalidated.
virtual void	LayoutChanged ()
	Hook function that is called when the layout if this view, or one of its children, has changed.
status_t	ScrollWithMouseWheelDelta (BScrollBar *, float)
	Handle the scroll wheel changing over scrollbars.
virtual void	DoLayout ()
	Layout view within the layout context.
virtual bool	GetToolTipAt (BPoint point, BToolTip **_tip)
	Point _tip with the view's tool tip.

Detailed Description

A view that allows the user drag and drop a target view.

The target view must be its immediate relative–a sibling, a parent, or single child. The target BView must be able to be archived.

The dragger draws a handle on top of the target view, usually in the bottom left the corner that the user can grab. When the user drags the handle the target view appears to move with the handle.

However the target view doesn't actually move, instead, the view is archived into a BMessage object and the BMessage object is dragged. When the BMessage is dropped, the target BView is reconstructed from the archive (along with the BDragger). The new object is a a replicant of the target view.

An example of a dragger handle on the Clock app can be seen below.

This class is tied closely to BShelf. A BShelf object accepts dragged BViews, reconstructs them from their archives and adds them to the view hierarchy of another view.

The Show Replicants/Hide Replicants menu item in Deskbar shows and hides the BDragger handles.

Since

BeOS R3

Constructor & Destructor Documentation

BDragger() [1/2]

BDragger::BDragger	(	BRect	frame,
		BView *	target,
		uint32	resizingMode = B_FOLLOW_NONE,
		uint32	flags = B_WILL_DRAW
	)

Creates a new BDragger and sets its target view.

The target view must be its immediate relative–a sibling, a parent, or single child, however, the constructor does not establish this relationship for you.

Once you construct the BDragger you must do one of of these:

• Add the target as a child of the dragger.
• Add the dragger as a child of the target.
• Add the dragger as a sibling of the target.

If you add the target as a child of the dragger it should be its only child.

A BDragger draws in the right bottom corner of its frame rectangle. If the target view is a parent or a sibling of the dragger then the frame rectangle needs to be no larger than the handle. However, if the target is a child of the dragger then the dragger's frame rectangle must enclose the target's frame so that the dragger doesn't clip the target.

Parameters

frame	The frame rectangle that the dragger is draw into.
target	The view to set the dragger to.
resizingMode	Sets the parameters by which the dragger can be resized. See BView for more information on resizing options.
flags	The flags mask sets what notifications the BDragger can receive. See BView for more information on flags.

Since

BeOS R3

BDragger() [2/2]

BDragger::BDragger

(

BMessage *

data

)

Constructs a BDragger object from message data.

Parameters

data	The message data to restore from.

Since

BeOS R3

~BDragger()

BDragger::~BDragger ( )

virtual

Destroys the BDragger object and frees the memory it uses, primarily from the bitmap handle.

Since

BeOS R3

Member Function Documentation

AllAttached()

virtual void BDragger::AllAttached ( )

virtual

Similar to AttachedToWindow() but this method is triggered after all child views have already been attached to a window.

Since

BeOS R3

Reimplemented from BView.

AllDetached()

virtual void BDragger::AllDetached ( )

virtual

Similar to AttachedToWindow() but this method is triggered after all child views have already been detached from a window.

Since

BeOS R3

Reimplemented from BView.

Archive()

status_t BDragger::Archive ( BMessage *  data, bool  deep = true  ) const

virtual

Archives the draggers's relationship to the target view.

The deep parameter has no effect on the BDragger object but is passed on to BView::Archive().

Returns

A status code, typically B_OK or B_ERROR on error.

See also

BView::Archive()

Since

BeOS R3

Reimplemented from BView.

AreDraggersDrawn()

static bool BDragger::AreDraggersDrawn ( )

static

Returns whether or not draggers are currently drawn.

Returns

true if draggers are drawn, false otherwise.

Since

BeOS R3

AttachedToWindow()

void BDragger::AttachedToWindow ( )

virtual

Puts the BDragger under the control of HideAllDraggers() and ShowAllDraggers().

Since

BeOS R3

Reimplemented from BView.

DetachedFromWindow()

void BDragger::DetachedFromWindow ( )

virtual

Removes the BDragger from the control of HideAllDraggers() and ShowAllDraggers().

Since

BeOS R3

Reimplemented from BView.

Draw()

void BDragger::Draw ( BRect  updateRect )

virtual

Draws the dragger handle.

Parameters

updateRect

The rectangular area to draw the handle in.

Since

BeOS R3

Reimplemented from BView.

FrameMoved()

virtual void BDragger::FrameMoved ( BPoint  newPosition )

virtual

Hook method called when the view is moved.

Parameters

newPosition

The point of the top left corner of the frame that the view has been moved to.

Since

BeOS R3

Reimplemented from BView.

FrameResized()

virtual void BDragger::FrameResized ( float  newWidth, float  newHeight  )

virtual

Hook method called when the view is resized.

Parameters

newWidth	The new width of the view.
newHeight	The new height of the view.

Since

BeOS R3

Reimplemented from BView.

GetPreferredSize()

virtual void BDragger::GetPreferredSize ( float *  _width, float *  _height  )

virtual

Fill out the preferred width and height of the view into the _width and _height parameters.

Derived classes should override this method to set the preferred size of object.

Remarks

Either the _width or _height parameter may be set to NULL if you only want to get the other one.

Parameters

[out]	_width	Pointer to a float to store the width of the view.
[out]	_height	Pointer to a float to store the height of the view.

Since

BeOS R3

Reimplemented from BView.

GetSupportedSuites()

virtual status_t BDragger::GetSupportedSuites ( BMessage *  data )

virtual

Reports the suites of messages and specifiers that derived classes understand.

Since

BeOS R3

Reimplemented from BView.

HideAllDraggers()

static status_t BDragger::HideAllDraggers ( )

static

Hides all BDragger objects so that they're not visible on screen.

The Hide Replicants menu item in Deskbar does its work through this method.

Returns

A status code, B_OK on success or an error code on failure.

Since

BeOS R3

Instantiate()

static BArchivable * BDragger::Instantiate ( BMessage *  data )

static

Creates a new BDragger object from the BMessage constructor.

Returns

A newly created BDragger or NULL if the message doesn't contain an archived BDragger object.

Since

BeOS R3

MakeFocus()

virtual void BDragger::MakeFocus ( bool  focus = true )

virtual

Makes the view the current focus view of the window or gives up being the window's focus view.

The focus view handles selections and KeyDown events when the the attached window is active. There can be only one focus view at a time per window.

When called with focus set to true this method first calls MakeFocus() on the previously focused view with focus set to false.

The focus doesn't automatically change when MouseDown() is called so calling MakeFocus() is the only way to make a view the focus view of a window. Classes derived from BView that can display the current selection, or that can accept pasted data should call MakeFocus() in their MouseDown() method to update the focus view of the window on click.

If the view isn't attached to a window this method has no effect.

Parameters

focus

true to set focus, false to remove it.

Since

BeOS R3

Reimplemented from BView.

MessageReceived()

void BDragger::MessageReceived ( BMessage *  msg )

virtual

Receives messages that control the visibility of the dragger handle.

Parameters

msg	The message received

See also

BView::MessageReceived()

Since

BeOS R3

Reimplemented from BView.

MouseDown()

void BDragger::MouseDown ( BPoint  point )

virtual

Hook method that is called when a mouse button is pressed over the dragger.

This results in the archiving of the target view and the dragger and initiates a drag-and-drop operation.

Parameters

point

The point on the screen where the mouse pointer is when the mouse is clicked.

Since

BeOS R3

Reimplemented from BView.

MouseMoved()

virtual void BDragger::MouseMoved ( BPoint  where, uint32  code, const BMessage *  dragMessage  )

virtual

Hook method called when the mouse is moved.

Parameters

where	The new location of the mouse in the view's coordinate system.
code	One of the following: B_ENTERED_VIEW The cursor has just entered the view. B_INSIDE_VIEW The cursor is inside the view. B_EXITED_VIEW The cursor has left the view's bounds. This only gets sent if the scope of the mouse events that the view can receive has been expanded by SetEventMask() or SetMouseEventMask(). B_OUTSIDE_VIEW The cursor is outside the view. This only gets sent if the scope of the mouse events that the view can receive has been expanded by SetEventMask() or SetMouseEventMask().
dragMessage	If a drag-and-drop operation is taking place this is a pointer to a BMessage that holds the drag information, otherwise the pointer is NULL.

See also

SetEventMask(), SetMouseEventMask()

DragMessage()

Since

BeOS R3

Reimplemented from BView.

MouseUp()

virtual void BDragger::MouseUp ( BPoint  where )

virtual

Hook method called when a mouse button is released.

Parameters

where

The point on the screen where the mouse pointer is when the mouse button is released.

Note

Calling GetMouse() in MouseUp() will return the new state of the mouse buttons (after the mouse button was released). If you want to know which button was released, you have to compare that with the previous state of the buttons, that you can memorize for example by calling GetMouse() in MouseDown().

Since

BeOS R3

Reimplemented from BView.

Perform()

virtual status_t BDragger::Perform ( perform_code  code, void *  _data  )

virtual

Perform some action. (Internal Method)

This method is available to allow classes to be extended while maintaining binary compatibility.

The following perform codes are recognized:

• PERFORM_CODE_MIN_SIZE:
• PERFORM_CODE_MAX_SIZE:
• PERFORM_CODE_PREFERRED_SIZE:
• PERFORM_CODE_LAYOUT_ALIGNMENT:
• PERFORM_CODE_HAS_HEIGHT_FOR_WIDTH:
• PERFORM_CODE_GET_HEIGHT_FOR_WIDTH:
• PERFORM_CODE_SET_LAYOUT:
• PERFORM_CODE_INVALIDATE_LAYOUT:
• PERFORM_CODE_DO_LAYOUT:
• PERFORM_CODE_GET_TOOL_TIP_AT:
• PERFORM_CODE_ALL_UNARCHIVED:
• PERFORM_CODE_ALL_ARCHIVED:

Parameters

code	The perform code.
_data	A pointer to store some data.

Returns

A status code.

Since

Haiku R1

Reimplemented from BView.

ResizeToPreferred()

virtual void BDragger::ResizeToPreferred ( )

virtual

Resizes the view to its preferred size keeping the position of the left top corner constant.

Warning

It is not recommended to use this method for views that are part of a BLayout.

Since

BeOS R3

Reimplemented from BView.

ResolveSpecifier()

virtual BHandler * BDragger::ResolveSpecifier ( BMessage *  message, int32  index, BMessage *  specifier, int32  what, const char *  property  )

virtual

Determine the proper handler for a scripting message.

Parameters

message	The scripting message to determine the handler.
index	The index of the specifier.
specifier	The message which contains the specifier.
what	The 'what' field of the specifier message.
property	The name of the target property.

Returns

A pointer to the proper BHandler for the given scripting message.

Since

BeOS R3

Reimplemented from BView.

ShowAllDraggers()

static status_t BDragger::ShowAllDraggers ( )

static

Causes all BDragger objects to draw their handles.

The Show Replicants menu item in Deskbar does its work through this method.

Returns

A status code, B_OK on success or an error code on failure.

Since

BeOS R3