Class: Controller

• Inheritance
• Description
• Class protocol
  • instance creation
• Instance protocol
  • Compatibility-ST80
  • accessing
  • event handling
  • initialization & release
  • menus

Inheritance:

   Object
   |
   +--Controller
      |
      +--ButtonController
      |
      +--CodeController
      |
      +--DialogCompositeController
      |
      +--ListViewController
      |
      +--MouseMenuController
      |
      +--ParagraphEditor
      |
      +--SelectionInListController
      |
      +--StandardSystemController
      |
      +--TextController
      |
      +--VariablePanelController
      |
      +--VisualWorks::Controller

Package:

stx:libview

Category:

Interface-Support-Controllers

Version:

rev: 1.64 date: 2023/05/27 10:38:00

user: cg

file: Controller.st directory: libview

module: stx stc-classLibrary: libview

Description:

Controllers can be used to control the user-interactions
to a model which is shown in a view.

For very simple views (and due to the evolution of Smalltalk/X),
many view-classes have the controller function integrated.

To allow both controller and non-controller operation, events are
sent directly to the view, if the view has no controller
(i.e. if it's controller instance variable is nil).
Otherwise, the controller gets the event message.

For now (vsn 2.10.4) there are only a few view classes using controllers;
however, over time, more will be converted, since separating the controller
offers much more flexibility
(although view initialization becomes a bit more complex).

Over time, expect the buttonPress/Release/Motion and keyPress/Release
methods to vanish from the view classes and corresponding controllers to
be appearing.
This migration should be backward compatible.

Device coordinates vs. Logical coordinates:
    if the view has a non-identity transformation (for example: drawing
    in millimeters or inches), the application/controller may or may not
    be interested in device coordinates in button/key events.
    Most are not, these will receive logical coordinates transparently
    in theyr button/key-Press/Release/Motion methods.
    Those which are interested should redefine the corresponding
    device-Key/Button-Press/Release/Motion methods.
    Of course, it is always possible to map between device and logical
    coordinates, using `view transformation applyTo/applyInverseTo:',
    if both coordinates are required (which is unlikely).

[Instance variables:]
    view        <View>               the view I control

    model       <Model>              the model which is to be worked on

copyright
COPYRIGHT (c) 1992 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:

 new

(comment from inherited method)
return an instance of myself without indexed variables

Instance protocol:

 blueButtonActivity

actually, this should be called 'rightButtonActivity'.
But for ST-80 compatibility ....

 controlInitialize

 isVisualWorksController

(comment from inherited method)
Modified (format): / 12-01-2022 / 09:52:56 / cg

 open

open my view

 poll

ST-80 compatibility - ignored here

 redButtonActivity

actually, this should be called 'leftButtonActivity'.
But for ST-80 compatibility ....

 yellowButtonActivity

actually, this should be called 'middleButtonActivity'.
But for ST-80 compatibility ....

 menuHolder

by default, the model has to provide the menu

 menuPerformer

by default, the model is performing menu actions

 model

return my model

 model: aModel

set my model

 sensor

return my view's sensor

 view

return my view

 view: aView

set my view

 buttonMotion: buttonMask x: x y: y

mouse was moved with button pressed in my view; nothing done here

 buttonMultiPress: button x: x y: y

a mouse button was pressed again shortly after in my view

 buttonPress: button x: x y: y

a mouse button was pressed in my view.
Translate buttonPress events into similar ST-80 type
event messages. This method and/or these ST-80 methods
can be redefined in subclasses

 buttonRelease: button x: x y: y

a mouse button was released in my view; nothing done here

 deviceButtonMotion: state x: x y: y

this is the low-level (untransformed) event as received
from the device (i.e. coordinates are in device coordinates).
If there is a transformation, apply the inverse
and send a buttonMotion with the logical coordinates.

Controllers which are interested in deviceCoordinates should
redefine this method -
those which are interested in logical coordinates
should redefine #buttonMotion:x:y:

 deviceButtonMultiPress: button x: x y: y

this is the low-level (untransformed) event as received
from the device (i.e. coordinates are in device coordinates).
If there is a transformation, apply the inverse
and send a buttonMultiPress with the logical coordinates.

Controllers which are interested in deviceCoordinates should
redefine this method -
those which are interested in logical coordinates
should redefine #buttonMultiPress:x:y:

 deviceButtonPress: button x: x y: y

this is the low-level (untransformed) event as received
from the device (i.e. coordinates are in device coordinates).
If there is a transformation, apply the inverse
and send a buttonPress with the logical coordinates.

Controllers which are interested in deviceCoordinates should
redefine this method -
those which are interested in logical coordinates
should redefine #buttonPress:x:y:

 deviceButtonRelease: button x: x y: y

this is the low-level (untransformed) event as received
from the device (i.e. coordinates are in device coordinates).
If there is a transformation, apply the inverse
and send a buttonRelease with the logical coordinates.

Controllers which are interested in deviceCoordinates should
redefine this method -
those which are interested in logical coordinates
should redefine #buttonRelease:x:y:

 deviceKeyPress: key x: x y: y

this is the low-level (untransformed) event as received
from the device (i.e. coordinates are in device coordinates).
If there is a transformation, apply the inverse
and send a keyPress with the logical coordinates.

Controllers which are interested in deviceCoordinates should
redefine this method -
those which are interested in logical coordinates
should redefine #keyPress:x:y:

 deviceKeyRelease: key x: x y: y

this is the low-level (untransformed) event as received
from the device (i.e. coordinates are in device coordinates).
If there is a transformation, apply the inverse
and send a keyRelease with the logical coordinates.

Controllers which are interested in deviceCoordinates should
redefine this method -
those which are interested in logical coordinates
should redefine #keyRelease:x:y:

 devicePointerEnter: state x: x y: y

this is the low-level (untransformed) event as received
from the device (i.e. coordinates are in device coordinates).
If there is a transformation, apply the inverse
and send a pointerEnter with the logical coordinates.

Controllers which are interested in deviceCoordinates should
redefine this method -
those which are interested in logical coordinates
should redefine #pointerEnter:x:y:

 focusIn

my view got the keyboard focus; nothing done here

 focusOut

my view lost keyboard focus; nothing done here

 keyPress: key x: x y: y

key was pressed in my view; nothing done here,
except for Tab keys.

 keyRelease: key x: x y: y

key was released in my view; nothing done here

 mouseWheelMotion: event x: x y: y amount: amount deltaTime: deltaTime

a mouse wheel was turned - nothing done here

 pointerEnter: state x: x y: y

mouse pointer entered my view; nothing done here

 pointerLeave: state

mouse pointer left my view; nothing done here