"

 COPYRIGHT (c) 1995 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.

"

'From Smalltalk/X, Version:2.10.5 on 4-may-1995 at 6:17:35 am'!

Controller subclass:#ButtonController

	 instanceVariableNames:'enableChannel pressChannel releaseChannel

		pressed active entered isTriggerOnDown autoRepeat

		repeatBlock initialDelay repeatDelay pressActionBlock

		releaseActionBlock isToggle'

	 classVariableNames:''

	 poolDictionaries:''

	 category:'Interface-Support-Controllers'

!

!ButtonController class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 1995 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.

"

!

version

"

"

!

documentation

"

    ButtonControllers are used with buttons and handle all user interaction.

    These are automatically created when a Button is created, therefore no manual

    action is required for creation.

    In normal applications, you dont have to care for the controller; 

    access to the controllers behavior is possible via messages to the button.

    (setting actions, controlling autorepeat etc.)

    See examples in the Button class.

    Instance variables:

      enableChannel           <ValueHolder    pressing is allowed (default: true)

			       on Boolean>    

      pressed                 <Boolean>       true if currently pressed (read-only)

      entered                 <Boolean>       true if the cursor is currently in this view

      isTriggerOnDown         <Boolean>       controls if the action should be executed on

					      press or on release (default: on release).

      isToggle                <Boolean>       controls if the button should show toggle

					      behavior (as opposed to one-shot behavior)

      pressActionBlock        <Block>         block to evaluate when pressed (default: noop)

      releaseActionBlock      <Block>         block to evaluate when released (default: noop)

      autoRepeat              <Boolean>       auto-repeats when pressed long enough (default: false)

      initialDelay            <Number>        seconds till first auto-repeat (default: 0.2)

      repeatDelay             <Number>        seconds of repeat intervall (default: 0.025)

      repeatBlock             <Block>         block evaluated for auto-repeat (internal)

      active                  <Boolean>       true during action evaluation (internal)

"

! !

!ButtonController class methodsFor:'defaults'!

defaultRepeatDelay

    "when autorepeat is enabled, and button is not released,

     repeat every repeatDelay seconds"

    ^ 0.025

!

defaultInitialDelay

    "when autorepeat is enabled, and button is not released,

     start repeating after initialDelay seconds"

    ^ 0.2

! !

!ButtonController methodsFor:'accessing-state'!

pressed

    "return true, if I am pressed"

    ^ pressed

!

active

    "return true, if I am active; 

     that is: currently performing my action.

     This query can be used to avoid multiple redraws."

    ^ active

!

enabled

    "return true, if I am enabled"

    ^ enableChannel value

!

entered

    "return true, if the mouse pointer is currently in my view"

    ^ entered

!

entered:aBoolean

    entered := aBoolean

!

active:aBoolean

    active := aBoolean

!

pressed:aBoolean

    pressed := aBoolean

! !

!ButtonController methodsFor:'accessing-channels'!

enableChannel

    "return the valueHolder which holdes the enable

     boolean value"

    ^ enableChannel

!

enableChannel:aValueHolder

    "set the valueHolder, which holds the enable boolean value"

    enableChannel notNil ifTrue:[

	enableChannel retractInterrestFor:self. 

    ].

    enableChannel := aValueHolder.

    aValueHolder onChangeSend:#enableStateChange to:self.

    view notNil ifTrue:[

	view redraw

    ]

!

pressChannel:aChannel

    pressChannel := aChannel

!

releaseChannel:aChannel

    releaseChannel := aChannel

! !

!ButtonController methodsFor:'accessing-behavior'!

beTriggerOnDown

    "make the receiver act on button press"

    isTriggerOnDown := true

!

beTriggerOnUp

    "make the receiver act on button release"

    isTriggerOnDown := false

!

triggerOnDown:aBoolean

    "set/clear the flag which controls if the action block is to be evaluated

     on press or on release. 

     (see also ST-80 compatibility methods beTriggerOn*)"

    isTriggerOnDown := aBoolean

!

isTriggerOnDown

    "return true, if I trigger on press

     (in contrast to triggering on up, which is the default)"

    ^ isTriggerOnDown

!

beToggle

    "make the receiver act like a toggle"

    isTriggerOnDown := true.

    isToggle := true

!

autoRepeat

    "turn on autorepeat"

    autoRepeat := true.

    repeatBlock := [self repeat]

!

action:aBlock

    "convenient method: depending on the setting the triggerOnDown flag,

     either set the press-action clear any release-action or

     vice versa, set the release-action and clear the press-action."

    isTriggerOnDown ifTrue:[

	releaseActionBlock := nil.

	pressActionBlock := aBlock

    ] ifFalse:[

	releaseActionBlock := aBlock.

	pressActionBlock := nil

    ]

!

pressAction:aBlock

    "define the action to be performed on press"

    pressActionBlock := aBlock

!

releaseAction:aBlock

    "define the action to be performed on release"

    releaseActionBlock := aBlock

!

toggleNoAction

    "toggle, but do NOT perform any action"

    pressed ifTrue:[

	view turnOff.

	pressed := false.

    ] ifFalse:[

	view turnOn.

	pressed := true.

    ].

!

toggle

    "toggle and perform the action"

    enableChannel value ifTrue:[

	self toggleNoAction.

	self performAction.

	view changed:#toggle with:pressed

    ]

!

pressAction

    "return the pressAction; thats the block which gets evaluated

     when the button is pressed (if non-nil)"

    ^ pressActionBlock

!

releaseAction

    "return the releaseAction; thats the block which gets evaluated

     when the button is relreased (if non-nil)"

    ^ releaseActionBlock

!

enable

    "enable the button"

    enableChannel value ifFalse:[

	enableChannel value:true.

	"/ view redraw    - not needed; button listenes to enableChannel

    ]

!

disable

    "disable the button"

    enableChannel value ifTrue:[

	enableChannel value:false.

	"/ view redraw    - not needed; button listenes to enableChannel

    ]

! !

!ButtonController methodsFor:'event handling'!

buttonPress:button x:x y:y

    (button == 1 or:[button == #select]) ifFalse:[

	^ super buttonPress:button x:x y:y

    ].

    enableChannel value ifTrue:[

	isToggle ifTrue:[

	    self toggle.

	    ^ self

	].

	pressed ifFalse:[

	    pressed := true.

	    view showActive.

	    (pressActionBlock notNil or:[model notNil]) ifTrue:[

		"

		 force output - so that button is drawn correctly in case

		 of any long-computation (at high priority)

		"

		view device flush.

	    ].

	    self performAction.

	    autoRepeat ifTrue:[

		Processor addTimedBlock:repeatBlock afterSeconds:initialDelay

	    ]

	]

    ]

!

buttonRelease:button x:x y:y

    "button was released - if enabled, perform releaseaction"

    (button == 1 or:[button == #select]) ifFalse:[

	^ super buttonRelease:button x:x y:y

    ].

    isToggle ifTrue:[

	^ self

    ].

    pressed ifTrue:[

	autoRepeat ifTrue:[

	    Processor removeTimedBlock:repeatBlock

	].

	pressed := false.

	view showPassive.

	enableChannel value ifTrue:[

	    "

	     only perform action if released within myself

	    "

	    ((x >= 0) 

	    and:[x <= view width

	    and:[y >= 0

	    and:[y <= view height]]]) ifTrue:[

		(releaseActionBlock notNil or:[model notNil]) ifTrue:[

		    "

		     force output - so that button is drawn correctly in case

		     of any long-computation (at high priority)

		    "

		    view device flush.

		].

		self performAction.

	    ]

	]

    ]

!

pointerEnter:state x:x y:y

    "mouse pointer entered my view.

     Redraw with enteredColors if they differ from the normal colors"

    entered := true.

    enableChannel value ifTrue:[

	pressed ifTrue:[

	    "

	     reentered after a leave with mouse-button down;

	     restart autorepeating and/or if I am a button with

	     triggerOnDown, show active again.

	    "

	    autoRepeat ifTrue:[

		Processor addTimedBlock:repeatBlock afterSeconds:initialDelay

	    ].

	    isTriggerOnDown ifFalse:[

		view showActive.

	    ]

	] ifFalse:[

	    view redraw

	]

    ]

!

pointerLeave:state

    "mouse pointer left my view.

     Redraw with normal colors if they differ from enteredColors"

    entered := false.

    pressed ifTrue:[

	"

	 leave with mouse-button down;

	 stop autorepeating and/or if I am a button with

	 action on release, show passive

	"

	autoRepeat ifTrue:[

	    Processor removeTimedBlock:repeatBlock

	].

	isTriggerOnDown ifFalse:[

	    view showPassive.

	]

    ] ifFalse:[

	enableChannel value ifTrue:[

	    view redraw

	]

    ]

!

performAction

    isToggle ifTrue:[

	value := pressed

    ] ifFalse:[

	value := true

    ].

    "

     ST/X style actionBlock evaluation & channel notification ...

    "

    pressed ifTrue:[

	action := pressActionBlock.

    ] ifFalse:[

	action := releaseActionBlock.

    ].

    action notNil ifTrue:[

	active := true.

	action numArgs == 0 ifTrue:[

	    action value

	] ifFalse:[

	    action value:value

	].

	active := false.

    ].

    ].

    "

     ST-80 style model notification ...

    "

    (isToggle

    or:[(isTriggerOnDown and:[pressed])

    or:[isTriggerOnDown not and:[pressed not]]]) ifTrue:[

	"the ST-80 way of doing things"

	view notNil ifTrue:[

	    active := true.

	    view sendChangeMessageWith:value.

	    active := false.

	].

    ].

!

buttonMultiPress:button x:x y:y

    ^ self buttonPress:button x:x y:y

!

keyPress:key x:x y:y

    "trigger on Return and space, if I am the focusView of my group

     (i.e. if I got an explicit focus)"

    (key == #Return or:[key == Character space]) ifTrue:[

	view hasFocus ifTrue:[

	    "just simulate a buttonPress/release here."

	    self buttonPress:1 x:0 y:0.

	    self buttonRelease:1 x:0 y:0.

	    ^ self.

	]

    ].

    view keyPress:key x:x y:y

!

repeat

    "this is sent from the autorepeat-block, when the button has been pressed long

     enough; it simulates a release-press, by evaluating both release

     and press actions."

    pressed ifTrue:[

	enableChannel value ifTrue:[

	    active ifFalse:[

		active := true.

		releaseActionBlock notNil ifTrue:[releaseActionBlock value].