Class: VUMeter

• Inheritance
• Description
• Class protocol
  • image specs
• Instance protocol
  • change & update
  • drawing
  • initialization & release
  • queries
• Examples

Inheritance:

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

Package:

stx:libwidg3

Category:

Views-Misc

Version:

rev: 1.12 date: 2022/01/13 19:42:45

user: cg

file: VUMeter.st directory: libwidg3

module: stx stc-classLibrary: libwidg3

Description:

nice display of a measurement value or simular...
model value must be 0..1


[instance variables:]

[class variables:]

copyright
COPYRIGHT (c) 2009 by 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.

Class protocol:

 offImage

This resource specification was automatically generated
by the ImageEditor of ST/X.

Usage example(s):

self offImage inspect ImageEditor openOnClass:self andSelector:#offImage Icon flushCachedIcons

 onImage

This resource specification was automatically generated
by the ImageEditor of ST/X.

Usage example(s):

self onImage inspect ImageEditor openOnClass:self andSelector:#onImage Icon flushCachedIcons

 poti1

This resource specification was automatically generated
by the ImageEditor of ST/X.

Usage example(s):

self poti1 inspect ImageEditor openOnClass:self andSelector:#poti1 Icon flushCachedIcons

 poti2

This resource specification was automatically generated
by the ImageEditor of ST/X.

Usage example(s):

self poti2 inspect ImageEditor openOnClass:self andSelector:#poti2 Icon flushCachedIcons

Instance protocol:

 update: something with: aParameter from: changedObject

Invoked when an object that I depend upon sends a change notification.

 redrawValue

map 0..1 into 0..pi scaling and shifting the phase

 redrawX: x y: y width: w height: h

called to redraw a part of the widgets area. x/y define the origin, w/h the size of
that area. The clipping region has already been set by the caller, so even if the code
below draws outside the redraw-area, it will not affect what is on the screen.
Therefore, the example below can fill the rectangle in the redraw area, but still draw
the cross in the outside regions.

 initialize

self new open

 computePreferredExtent

(comment from inherited method)
return my computed preferred extent - this is the minimum size I would like to have.
If there are any components, a rectangle enclosing them
is returned. Otherwise, the actual extent is returned.

Examples:

   VUMeter new open

   |top v|

   top := StandardSystemView new.
   top extent:300@300.
   v := VUMeter new.
   v origin:10@10 corner:150@150.
   top add:v.
   top open

   |m top v stop b|

   m := 0 asValue.

   top := StandardSystemView new.
   top extent:300@300.
   v := VUMeter new.
   v model:m.
   v origin:10@10 corner:150@150.
   top add:v.
   top open.

   stop := false asValue.
   (b:= Button label:'stop') model:stop; open.
   [
       [stop value] whileFalse:[
         0 to:1 by:0.1 do:[:v  |
           m value:v.
           Delay waitForSeconds:0.5
         ]
       ].
       top destroy.
       b destroy.
   ] fork.