Class: ThumbWheel

• Inheritance
• Description
• Instance protocol
  • accessing
  • accessing-behavior
  • accessing-look
  • change & update
  • drawing
  • event handling
  • events
  • forced scroll
  • initialization
  • private
  • queries
• Examples

Inheritance:

   Object
   |
   +--GraphicsMedium
      |
      +--DisplaySurface
         |
         +--SimpleView
            |
            +--View
               |
               +--ThumbWheel

Package:

stx:libwidg2

Category:

Views-Interactors

Version:

rev: 1.47 date: 2023/07/06 14:35:44

user: cg

file: ThumbWheel.st directory: libwidg2

module: stx stc-classLibrary: libwidg2

Description:

A thumbWheel is like a slider, but looks different ...
ThumbWheels are useful with 3D applications, to control
things like rotation, translation and magnification.

copyright
COPYRIGHT (c) 1996 by eXept Software AG / Claus Gittinger
             All Rights Reserved

This software is furnished under a license and may be used
only in accordance with the terms of that license and with the
inclusion of the above copyright notice.   This software may not
be provided or otherwise made available to, or used by, any
other person.  No title to or ownership of the software is
hereby transferred.

Instance protocol:

 keyboardStep

return the scrollers keyboard step. If non-nil,
that's the stepping value used with cursorUp/cursorDown keys.
(not used with Scrollers, but provided for subclasses)

 keyboardStep: aNumber

set the scrollers keyboard step. If non-nil,
that's the stepping value used with cursorUp/cursorDown keys.
(not used with Scrollers, but provided for subclasses)

 start

return the wheel's range minimum.

 start: aNumber

set the wheel's range minimum.

 start: start stop: stop

set the wheel's range.

 step

return the wheel's range step.

 step: aNumber

set the wheel's range step.

 stop

return the wheel's range end.

 stop: aNumber

set the wheel's range end.

 thumbOrigin: pos

same as thumbPosition (for protocol compatibility with sliders)

 thumbPosition

return the position

 thumbPosition: pos

set the wheel's position;
the argument should be in the start..stop interval.

 endMoveAction

return the endMoveAction, a block which is evaluated when the wheel
stops to move (i.e. the user releases the mouse).
The default is nil (i.e. no action)

 endMoveAction: aBlock

set the endMoveAction, a block which is evaluated when the wheel
stops to move (i.e. the user releases the mouse).

 endlessRotation: aBoolean

if true, rotation wraps and endless rotation is permitted.
If false (the default), rotation ends at rangeStart/rangeEnd.

 scrollAction

return the scrollAction, a block which is evaluated when the wheel
is turned (i.e. for every change).

 scrollAction: aBlock

set the scrollAction, a block which is evaluated when the wheel
is turned (i.e. for every change).

 startMoveAction

return the startMoveAction, a block which is evaluated when the wheel
starts to turn (i.e. the user clicks on it).
The default is nil (i.e. no action)

 startMoveAction: aBlock

set the startMoveAction, a block which is evaluated when the wheel
starts to turn (i.e. the user clicks on it).

 orientation

return the wheels orientation; #horizontal or #vertical

 orientation: aSymbol

set the wheels orientation; the argument may be one of
#horizontal or #vertical

 update: something with: aParameter from: changedObject

handle update from a model (if any)

 redrawX: x y: y width: w height: h

redraw the thumbWheel.
Q: is it worth the effort - or should we simply use some bitmap ?

 buttonMotion: state x: x y: y

scale acc. to angleRange

 buttonPress: button x: x y: y

fetch the current value; to avoid a jump.

 buttonRelease: button x: x y: y

(comment from inherited method)
button was released - check my components for a hit.

 keyPress: key x: x y: y

(comment from inherited method)
a key has been pressed. If there are components,
pass it to the corresponding one.
Otherwise, forward it to the superview, if there is any.

 sizeChanged: how from: oldExtentOrNil

my view has changed the size (not the contents)

  |top wheel|

  top := StandardSystemView new.
  top extent:200@200.

  wheel := ThumbWheel in:top.
  wheel orientation:#vertical.
  wheel level:1.

  wheel origin:0.0@0.0; extent:(wheel preferredExtent).

  top open.

  |top wheel1 wheel2|

  top := StandardSystemView new.
  top extent:200@200.

  wheel1 := ThumbWheel in:top.
  wheel1 orientation:#vertical.
  wheel1 level:1.

  wheel1 origin:0.0@0.0; extent:(wheel1 preferredExtent).

  wheel2 := ThumbWheel in:top.
  wheel2 orientation:#horizontal.
  wheel2 level:1.

  wheel2 origin:0.0@1.0; extent:(wheel2 preferredExtent).
  wheel2 topInset:(wheel2 preferredExtent y negated).
  wheel2 bottomInset:(wheel2 preferredExtent y).
  top open.

  |top wheel|

  top := StandardSystemView new.
  top extent:200@200.

  wheel := ThumbWheel in:top.
  wheel orientation:#vertical.
  wheel level:1.

  wheel origin:0.0@0.0; extent:(wheel preferredExtent).
  wheel scrollAction:[:value | Transcript showCR:value rounded].
  top open.

  |top wheel model|

  model := ValueHolder new.
  model
      onChangeSend:#value
      to:[Transcript show:'value now: '; showCR:model value rounded].

  top := StandardSystemView new.
  top extent:200@200.

  wheel := ThumbWheel in:top.
  wheel orientation:#vertical.
  wheel level:1.

  wheel origin:0.0@0.0; extent:(wheel preferredExtent).
  wheel model:model.
  top open.

  |top wheel model|

  model := ValueHolder new.
  model
      onChangeSend:#value
      to:[Transcript show:'value now: '; showCR:model value rounded].

  top := StandardSystemView new.
  top extent:200@200.

  wheel := ThumbWheel in:top.
  wheel orientation:#vertical.
  wheel level:1.
  wheel endlessRotation:true.

  wheel origin:0.0@0.0; extent:(wheel preferredExtent).
  wheel model:model.
  top open.

  |top wheel1 wheel2 image magX magY hHolder vHolder imageView|

  magX := magY := 1.

  hHolder := ValueHolder new.
  hHolder
      onChangeSend:#value
      to:[
          magX := hHolder value * 2 / 360.
          magX = 0 ifTrue:[magX := 0.01].
          Transcript show:'magX now '; showCR:magX.
          imageView clear.
          imageView magnification:magX@magY].

  vHolder := ValueHolder new.
  vHolder
      onChangeSend:#value
      to:[
          magY := vHolder value * 2 / 360.
          magY = 0 ifTrue:[magY := 0.01].
          Transcript show:'magY now '; showCR:magY.
          imageView clear.
          imageView magnification:magX@magY].

  top := StandardSystemView new.
  top extent:200@200.

  wheel1 := ThumbWheel in:top.
  wheel1 orientation:#vertical.
  wheel1 level:1.
  wheel1 origin:0.0@0.0; extent:(wheel1 preferredExtent).
  wheel1 model:vHolder.

  wheel2 := ThumbWheel in:top.
  wheel2 orientation:#horizontal.
  wheel2 level:1.
  wheel2 origin:0.0@1.0; extent:(wheel2 preferredExtent).
  wheel2 topInset:(wheel2 preferredExtent y negated).
  wheel2 bottomInset:(wheel2 preferredExtent y).
  wheel2 model:hHolder.

  imageView := ImageEditView in:top.
  imageView level:1.
  imageView origin:0.0@0.0 corner:1.0@1.0.
  imageView leftInset:(wheel1 preferredExtent x).
  imageView bottomInset:(wheel2 preferredExtent y).
  imageView image:(Image fromFile:'bitmaps/garfield.gif').
  top open.