Class: InputView

• Inheritance
• Description
• Instance protocol
  • accessing
  • drag & drop
  • event handling
  • initialization
  • redefined dummy
• Examples

Inheritance:

   Object
   |
   +--GraphicsMedium
      |
      +--DisplaySurface
         |
         +--SimpleView
            |
            +--InputView

Package:

stx:libview2

Category:

Views-Special

Version:

rev: 1.26 date: 2021/01/20 15:59:33

user: cg

file: InputView.st directory: libview2

module: stx stc-classLibrary: libview2

Description:

a view for input only - forwarding all events to another object.
This kind of view can be used to be laid on top of another view to catch all
input. (Interface builder)
NOTICE: the event forwarding is a leftover from times when no delegation mechanism
        existed - it will vanish - use delegates for new code.

[caveat:]
    do not use
    it seems to (no longer) work on the desktop (at least with win10).

copyright
COPYRIGHT (c) 1990 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.

Instance protocol:

 eventReceiver: aView

set the view to which input events are forwarded

 isInputOnly

return true, since this is a transparent input-only view

 canDrop: aDropContext

return true, if aCollectionOfDropObjects can be dropped here.
Delegated to my eventReceiving view

 canDrop: aDropContext at: aPoint

return true, if aCollectionOfDropObjects can be dropped here.
Delegated to my eventReceiving view

 canDropObjects: aCollectionOfDropObjects

return true, if aCollectionOfDropObjects can be dropped here.
Delegated to my eventReceiving view

 canDropObjects: aCollectionOfDropObjects at: aPoint

return true, if aCollectionOfDropObjects can be dropped here.
Delegated to my eventReceiving view

 drop: aDropContext

drop aCollectionOfDropObjects here.
Delegated to my eventReceiving view

 drop: aDropContext at: aPoint

drop aCollectionOfDropObjects here.
Delegated to my eventReceiving view

 dropObjects: aCollectionOfDropObjects

drop aCollectionOfDropObjects here.
Delegated to my eventReceiving view

 dropObjects: aCollectionOfDropObjects at: aPoint

drop aCollectionOfDropObjects here.
Delegated to my eventReceiving view

 buttonMotion: state x: x y: y

redefined to forward the event to my eventReceiver

 buttonPress: button x: x y: y

redefined to forward the event to my eventReceiver

 buttonRelease: button x: x y: y

redefined to forward the event to my eventReceiver

 exposeX: x y: y width: w height: h

dummy - will never be received

 focusIn

redefined to forward the event to my eventReceiver

 focusOut

redefined to forward the event to my eventReceiver

 keyPress: key x: x y: y

redefined to forward the event to my eventReceiver

 keyRelease: key x: x y: y

redefined to forward the event to my eventReceiver

 pointerEnter: state x: x y: y

redefined to forward the event to my eventReceiver

 pointerLeave: state

redefined to forward the event to my eventReceiver

 initialize

(comment from inherited method)
initialize all state of the view - usually redefined in subclasses,
but always doing a 'super initialize'. Each class should setup its
locals - and not forget the others.
View setup is separated into two parts, the general setup done here
and the style specific setup in initStyle. Each view should be prepared
for a stylechange by being sent another initStyle with a new style value.
(in this case, it should set all of its style-dependent things, but
leave the state and contents as-is)

 setViewBackground

dummy - inputviews have no background

Examples:

|v|

v := InputView origin:0@0 extent:Display extent.
[Delay waitForSeconds:5. v destroy] fork.
v open.