Panner Widget
Application header file <X11/Xaw/Panner.h>
Class header file <X11/Xaw/PannerP.h>
Class pannerWidgetClass
Class Name Panner
Superclass Simple
A Panner widget is a rectangle, called the
``canvas,'' on which another rectangle, the ``slider,'' moves in two
dimensions. It is often used with a Porthole widget to move, or
``scroll,'' a third widget in two dimensions, in which case the
slider's size and position gives feedback as to what portion of
the third widget is visible.
The slider may be scrolled around the canvas by pressing,
dragging, and releasing Button1; the default translation also
enables scrolling via arrow keys and some other keys. While
scrolling is in progress, the application receives notification
through callback procedures. Notification may be done either
continuously whenever the slider moves or discretely whenever the
slider has been given a new location.
Resources
When creating a Panner widget instance, the following resources are
retrieved from the argument list or from the resource database:
Name
Class
Type
Notes
Default Value
accelerators
Accelerators
AcceleratorTable
NULL
allowOff
AllowOff
Boolean
False
ancestorSensitive
AncestorSensitive
Boolean
D
True
background
Background
Pixel
XtDefaultBackground
backgroundPixmap
Pixmap
Pixmap
XtUnspecifiedPixmap
backgroundStipple
BackgroundStipple
String
NULL
borderColor
BorderColor
Pixel
XtDefaultForeground
borderPixmap
Pixmap
Pixmap
XtUnspecifiedPixmap
borderWidth
BorderWidth
Dimension
1
canvasHeight
CanvasHeight
Dimension
0
canvasWidth
CanvasWidth
Dimension
0
colormap
Colormap
Colormap
Parent's Colormap
cursor
Cursor
Cursor
None
cursorName
Cursor
String
NULL
defaultScale
DefaultScale
Dimension
8
depth
Depth
int
C
Parent's Depth
destroyCallback
Callback
XtCallbackList
NULL
foreground
Foreground
Pixel
XtDefaultForeground
height
Height
Dimension
A
depends on orientation
internalSpace
InternalSpace
Dimension
4
international
International
Boolean
C
False
lineWidth
LineWidth
Dimension
0
mappedWhenManaged
MappedWhenManaged
Boolean
True
pointerColor
Foreground
Pixel
XtDefaultForeground
pointerColorBackground
Background
Pixel
XtDefaultBackground
reportCallback
ReportCallback
Callback
NULL
resize
Resize
Boolean
True
rubberBand
RubberBand
Boolean
False
screen
Screen
Screen
R
Parent's Screen
sensitive
Sensitive
Boolean
True
shadowColor
ShadowColor
Pixel
XtDefaultForeground
shadowThickness
ShadowThickness
Dimension
2
sliderX
SliderX
Position
0
sliderY
SliderY
Position
0
sliderHeight
SliderHeight
Dimension
0
sliderWidth
SliderWidth
Dimension
0
translations
Translations
TranslationTable
See below
width
Width
Dimension
A
depends on orientation
x
Position
Position
0
y
Position
Position
0
allowOff
Whether to allow the edges of the slider to go off the edges of the canvas.
backgroundStipple
The name of a bitmap pattern to be used as the background for
the area representing the canvas.
canvasHeight
canvasWidth
The size of the canvas.
defaultScale
The percentage size that the Panner widget should have relative
to the size of the canvas.
foreground
A pixel value which indexes the widget's colormap to derive the color
used to draw the slider.
internalSpace
The width of internal border in pixels between a slider representing the
full size of the canvas
and the edge of the Panner widget.
lineWidth
The width of the lines in the rubberbanding rectangle when rubberbanding
is in effect instead of continuous scrolling. The default is 0.
reportCallback
All functions on this callback list are called when the
notify action is invoked. See the Panner Actions section
for details.
resize
Whether or not to resize the panner whenever the canvas size is changed so
that the defaultScale is maintained.
rubberBand
Whether or not scrolling should be discrete (only moving a rubberbanded
rectangle until the scrolling is done) or continuous (moving the slider
itself). This controls whether or not the move action procedure also
invokes the notify action procedure.
shadowColor
The color of the shadow underneath the slider.
shadowThickness
The width of the shadow underneath the slider.
sliderX
sliderY
The location of the slider in the coordinates of the canvas.
sliderHeight
sliderWidth
The size of the slider.
Panner Actions
The actions supported by the Panner widget are:
start()
This action begins movement of the slider.
stop()
This action ends movement of the slider.
abort()
This action ends movement of the slider and restores it to the position it
held when the start action was invoked.
move()
This action moves the outline of the slider (if the rubberBand resource
is True) or the slider itself (by invoking the notify
action procedure).
page(xamount,yamount)
This action moves the slider by the specified amounts. The format
for the amounts is a signed or unsigned floating-point number (e.g., +1.0
or \-.5) followed
by either p indicating pages (slider sizes), or c indicating
canvas sizes. Thus, page(+0,+.5p) represents vertical movement down
one-half the height of the slider and page(0,0) represents moving to
the upper left corner of the canvas.
notify()
This action informs the application of the slider's current position by
invoking the reportCallback functions registered by the application.
set(what,value)
This action changes the behavior of the Panner. The what argument
must currently be the string rubberband and controls the value of
the rubberBand resource. The value argument
may have one of the values on, off, or toggle.
The default bindings for Panner are:
<Btn1Down>: start(\|)
<Btn1Motion>: move(\|)
<Btn1Up>: notify(\|) stop(\|)
<Btn2Down>: abort(\|)
<Key>KP_Enter: set(rubberband,toggle)
<Key>space: page(+1p,+1p)
<Key>Delete: page(\-1p,\-1p)
<Key>BackSpace: page(\-1p,\-1p)
<Key>Left: page(\-.5p,+0)
<Key>Right: page(+.5p,+0)
<Key>Up: page(+0,\-.5p)
<Key>Down: page(+0,+.5p)
<Key>Home: page(0,0)
Panner Callbacks
The functions registered on the reportCallback list are invoked by
the notify action as follows:
void ReportProc
Widget panner
XtPointer client_data
XtPointer report
panner
Specifies the Panner widget.
panner
Specifies the client data.
panner
Specifies a pointer to an XawPannerReport structure containing
the location and size of the slider and the size of the canvas.