So *that's* what that is. This has been driving me nuts:) I went looking for the cause once but didn't find it. 

On iOS, where the fast VM can't be used, Morphic chunks a bit. As a result, there's a lot of latency between drag gestures and drag actions. As it is, the UI feels really wonky that way. I'm wondering if I can make it suck less by tweaking the drag threshold. 

If for some reason this became a user preference (exposed with method annotation) the first programmer guilty of doing the work and checking it in will receive a bottle of high end locally brewed India Pale Ale from the pacific northwest region of north America via postal mail. (I'm too busy with work to Squeak right now, pout.)

On Mar 3, 2011, at 3:07 AM, Nicolas Cellier <nicolas.cellier.aka.nice at gmail.com> wrote:

> Ah yes, thanks, this was getting really annoying even in Browser (I
> don't like the clink).
> 
> Nicolas
> 
> 2011/3/3 Chris Muller <asqueaker at gmail.com>:
>> Ever since this change, I have been getting quite a few accidental
>> drags when selecting methods, which is distracting because, with Maui
>> loaded, it instantiates a naked-object view from the dragged method
>> and I have to close it.
>> 
>> The DragThreshold variable is a good idea, but drag-threshold function
>> exists for a reason has effectively been nullified by the default
>> value of 0.
>> 
>> Therefore, I would like to change the default value back to 5, and
>> Cobalt will have to adjust it to 0..
>> 
>>  - Chris
>> 
>> On Mon, Feb 21, 2011 at 3:31 PM,  <commits at source.squeak.org> wrote:
>>> Matthew Fulmer uploaded a new version of Morphic to project The Trunk:
>>> http://source.squeak.org/trunk/Morphic-mtf.521.mcz
>>> 
>>> ==================== Summary ====================
>>> 
>>> Name: Morphic-mtf.521
>>> Author: mtf
>>> Time: 21 February 2011, 4:29:10.979 pm
>>> UUID: cf57b307-096f-4311-a02e-b1f53d206e9c
>>> Ancestors: Morphic-nice.520
>>> 
>>> created HandMorph >> dragThreshold to hold the default drag threshold
>>> 
>>> Changed drag users to use this setting rather than make up their own thresholds
>>> 
>>> Finished a partial change of SystemWindow from simulating its own dragging to using the builtin drag mechanism
>>> 
>>> Made the default drag threshold zero pixels. it was previously 0, 5, or 10 pixels, depending on the morph
>>> 
>>> =============== Diff against Morphic-nice.520 ===============
>>> 
>>> Item was changed:
>>>  ----- Method: ClickExerciser>>mouseDown: (in category 'event handling') -----
>>>  mouseDown: evt
>>>        "Do nothing upon mouse-down except inform the hand to watch for a
>>>        double-click; wait until an ensuing click:, doubleClick:, or drag:
>>>        message gets dispatched"
>>>        Preferences disable: #NewClickTest .
>>>        evt hand
>>>                waitForClicksOrDrag: self
>>>                event: evt
>>>                selectors: self selectors
>>> +               threshold: HandMorph dragThreshold!
>>> -               threshold: 10
>>> -       !
>>> 
>>> Item was changed:
>>>  ----- Method: HaloMorph>>blueButtonDown: (in category 'meta-actions') -----
>>>  blueButtonDown: event
>>>        "Transfer the halo to the next likely recipient"
>>>        target ifNil:[^self delete].
>>>        event hand obtainHalo: self.
>>>        positionOffset := event position - (target point: target position in: owner).
>>>        self isMagicHalo ifTrue:[
>>>                self isMagicHalo: false.
>>>                ^self magicAlpha: 1.0].
>>>        "wait for drags or transfer"
>>>        event hand
>>>                waitForClicksOrDrag: self
>>>                event: event
>>>                selectors: { #transferHalo:. nil. nil. #dragTarget:. }
>>> +               threshold: HandMorph dragThreshold!
>>> -               threshold: 5.!
>>> 
>>> Item was changed:
>>>  Morph subclass: #HandMorph
>>>        instanceVariableNames: 'mouseFocus keyboardFocus eventListeners mouseListeners keyboardListeners mouseClickState mouseOverHandler lastMouseEvent targetOffset damageRecorder cacheCanvas cachedCanvasHasHoles temporaryCursor temporaryCursorOffset hardwareCursor hasChanged savedPatch userInitials lastEventBuffer genieGestureProcessor keyboardInterpreter'
>>> +       classVariableNames: 'CompositionWindowManager DoubleClickTime DragThreshold EventStats NewEventRules NormalCursor PasteBuffer ShowEvents'
>>> -       classVariableNames: 'CompositionWindowManager DoubleClickTime EventStats NewEventRules NormalCursor PasteBuffer ShowEvents'
>>>        poolDictionaries: 'EventSensorConstants'
>>>        category: 'Morphic-Kernel'!
>>> 
>>>  !HandMorph commentStamp: '<historical>' prior: 0!
>>>  The cursor may be thought of as the HandMorph.  The hand's submorphs hold anything being carried by dragging.
>>> 
>>>  There is some minimal support for multiple hands in the same world.!
>>> 
>>> Item was added:
>>> + ----- Method: HandMorph class>>dragThreshold (in category 'accessing') -----
>>> + dragThreshold
>>> +
>>> +       ^ DragThreshold
>>> + !
>>> 
>>> Item was added:
>>> + ----- Method: HandMorph class>>dragThreshold: (in category 'accessing') -----
>>> + dragThreshold: pixels
>>> +
>>> +       DragThreshold := pixels!
>>> 
>>> Item was changed:
>>>  ----- Method: HandMorph class>>initialize (in category 'class initialization') -----
>>>  initialize
>>>        "HandMorph initialize"
>>> 
>>>        PasteBuffer := nil.
>>>        DoubleClickTime := 350.
>>> +       DragThreshold := 0.
>>>        NormalCursor := CursorWithMask normal asCursorForm.
>>>  !
>>> 
>>> Item was changed:
>>>  ----- Method: HandMorph>>waitForClicksOrDrag:event: (in category 'double click support') -----
>>>  waitForClicksOrDrag: aMorph event: evt
>>>        "Wait for mouse button and movement events, informing aMorph about events interesting to it via callbacks.
>>>        This message is typically sent to the Hand by aMorph when it first receives a mouse-down event.
>>>        The callback methods invoked on aMorph (which are passed a copy of evt) are:
>>>                #click: sent when the mouse button goes up within doubleClickTime.
>>>                #doubleClick:   sent when the mouse goes up, down, and up again all within DoubleClickTime.
>>>                #doubleClickTimeout:  sent when the mouse does not have a doubleClick within DoubleClickTime.
>>>                #startDrag:     sent when the mouse moves more than 10 pixels from evt's position within DoubleClickTime.
>>>        Note that mouseMove: and mouseUp: events are not sent to aMorph until it becomes the mouse focus,
>>>        which is typically done by aMorph in its click:, doubleClick:, or drag: methods."
>>> 
>>> +       ^self waitForClicksOrDrag: aMorph event: evt selectors: #( #click: #doubleClick: #doubleClickTimeout: #startDrag:) threshold: HandMorph dragThreshold!
>>> -       ^self waitForClicksOrDrag: aMorph event: evt selectors: #( #click: #doubleClick: #doubleClickTimeout: #startDrag:) threshold: 10
>>> - !
>>> 
>>> Item was changed:
>>>  ----- Method: Morph>>blueButtonDown: (in category 'meta-actions') -----
>>>  blueButtonDown: anEvent
>>>        "Special gestures (cmd-mouse on the Macintosh; Alt-mouse on Windows and Unix) allow a mouse-sensitive morph to be moved or bring up a halo for the morph."
>>>        | h tfm doNotDrag |
>>>        h := anEvent hand halo.
>>>        "Prevent wrap around halo transfers originating from throwing the event back in"
>>>        doNotDrag := false.
>>>        h ifNotNil:[
>>>                (h innerTarget == self) ifTrue:[doNotDrag := true].
>>>                (h innerTarget hasOwner: self) ifTrue:[doNotDrag := true].
>>>                (self hasOwner: h target) ifTrue:[doNotDrag := true]].
>>> 
>>>        tfm := (self transformedFrom: nil) inverseTransformation.
>>> 
>>>        "cmd-drag on flexed morphs works better this way"
>>>        h := self addHalo: (anEvent transformedBy: tfm).
>>>        h ifNil: [^ self].
>>>        doNotDrag ifTrue:[^self].
>>>        "Initiate drag transition if requested"
>>>        anEvent hand
>>>                waitForClicksOrDrag: h
>>>                event: (anEvent transformedBy: tfm)
>>>                selectors: { nil. nil. nil. #dragTarget:. }
>>> +               threshold: HandMorph dragThreshold.
>>> -               threshold: 5.
>>>        "Pass focus explicitly here"
>>>        anEvent hand newMouseFocus: h.!
>>> 
>>> Item was changed:
>>>  ----- Method: PasteUpMorph>>mouseDown: (in category 'event handling') -----
>>>  mouseDown: evt
>>>        "Handle a mouse down event."
>>>        | grabbedMorph handHadHalos |
>>> 
>>>        (Preferences generalizedYellowButtonMenu
>>>                        and: [evt yellowButtonPressed])
>>>                ifTrue: [^ self yellowButtonActivity: evt shiftPressed].
>>> 
>>>        grabbedMorph := self morphToGrab: evt.
>>>        grabbedMorph ifNotNil:[
>>>                grabbedMorph isSticky ifTrue:[^self].
>>>                self isPartsBin ifFalse:[^evt hand grabMorph: grabbedMorph].
>>>                grabbedMorph := grabbedMorph partRepresented duplicate.
>>>                grabbedMorph restoreSuspendedEventHandler.
>>>                (grabbedMorph fullBounds containsPoint: evt position)
>>>                        ifFalse:[grabbedMorph position: evt position].
>>>                "Note: grabbedMorph is ownerless after duplicate so use #grabMorph:from: instead"
>>>                ^ evt hand grabMorph: grabbedMorph from: self].
>>> 
>>>        (super handlesMouseDown: evt)
>>>                ifTrue:[^super mouseDown: evt].
>>> 
>>>        handHadHalos := evt hand halo notNil.
>>> 
>>>        evt hand removeHalo. "shake off halos"
>>>        evt hand releaseKeyboardFocus. "shake of keyboard foci"
>>> 
>>>        self submorphs
>>>                select:[:each | each hasProperty: #morphHierarchy]
>>>                thenDo:[:each | each delete].
>>> 
>>>        Preferences noviceMode
>>>                ifTrue:[
>>>                        self submorphs
>>>                                select:[:each | (each isKindOf: MenuMorph) and:[each stayUp not]]
>>>                                thenDo:[:each | each delete].
>>>                ].
>>> 
>>>        (evt shiftPressed not
>>>                        and:[ self isWorldMorph not
>>>                        and:[ self wantsEasySelection not ]])
>>>        ifTrue:[
>>>                "explicitly ignore the event if we're not the world and we'll not select,
>>>                so that we could be picked up if need be"
>>>                evt wasHandled: false.
>>>                ^ self.
>>>        ].
>>> 
>>>        ( evt shiftPressed or: [ self wantsEasySelection ] ) ifTrue:[
>>>                "We'll select on drag, let's decide what to do on click"
>>>                | clickSelector |
>>> 
>>>                clickSelector := nil.
>>> 
>>>                evt shiftPressed ifTrue:[
>>>                        clickSelector := #findWindow:.
>>>                ]
>>>                ifFalse:[
>>>                        self isWorldMorph ifTrue:[
>>>                                clickSelector := handHadHalos
>>>                                                                                ifTrue: [ #delayedInvokeWorldMenu: ]
>>>                                                                                ifFalse: [ #invokeWorldMenu: ]
>>>                        ]
>>>                ].
>>> 
>>>                evt hand
>>>                                waitForClicksOrDrag: self
>>>                                event: evt
>>>                                selectors: { clickSelector. nil. nil. #dragThroughOnDesktop: }
>>> +                               threshold: HandMorph dragThreshold.
>>> -                               threshold: 5.
>>>        ]
>>>        ifFalse:[
>>>                "We wont select, just bring world menu if I'm the world"
>>>                self isWorldMorph ifTrue:[
>>>                        handHadHalos
>>>                                ifTrue: [ self delayedInvokeWorldMenu: evt ]
>>>                                ifFalse: [ self invokeWorldMenu: evt ]
>>>                ]
>>>        ].
>>>  !
>>> 
>>> Item was changed:
>>>  ----- Method: PluggableListMorph>>mouseDown: (in category 'events') -----
>>>  mouseDown: evt
>>>        | selectors row |
>>>        evt yellowButtonPressed  "First check for option (menu) click"
>>>                ifTrue: [^ self yellowButtonActivity: evt shiftPressed].
>>>        row := self rowAtLocation: evt position.
>>>        row = 0  ifTrue: [^super mouseDown: evt].
>>>        "self dragEnabled ifTrue: [aMorph highlightForMouseDown]."
>>>        selectors := Array
>>>                with: #click:
>>>                with: (doubleClickSelector ifNotNil:[#doubleClick:])
>>>                with: nil
>>>                with: (self dragEnabled ifTrue:[#startDrag:] ifFalse:[nil]).
>>> +       evt hand waitForClicksOrDrag: self event: evt selectors: selectors threshold: HandMorph dragThreshold "pixels".!
>>> -       evt hand waitForClicksOrDrag: self event: evt selectors: selectors threshold: 10 "pixels".!
>>> 
>>> Item was removed:
>>> - ----- Method: PluggableSystemWindowWithLabelButton>>mouseDown: (in category 'events') -----
>>> - mouseDown: evt
>>> -       | wasInactive |
>>> -       wasInactive := TopWindow ~~ self.
>>> -       self valueOfProperty: #clickPoint ifPresentDo:
>>> -               [:firstClick |
>>> -               (labelButton containsPoint: evt cursorPoint) ifTrue:
>>> -                       [^labelButton mouseDown: evt]].
>>> -       super mouseDown: evt.
>>> -       (wasInactive
>>> -        and: [model windowActiveOnFirstClick not
>>> -        and: [labelButton containsPoint: evt cursorPoint]]) ifTrue:
>>> -               [^labelButton mouseDown: evt]!
>>> 
>>> Item was removed:
>>> - ----- Method: PluggableSystemWindowWithLabelButton>>passivate (in category 'top window') -----
>>> - passivate
>>> -       super passivate.
>>> -       self removeProperty: #clickPoint!
>>> 
>>> Item was changed:
>>>  ----- Method: SimpleHierarchicalListMorph>>mouseDown: (in category 'event handling') -----
>>>  mouseDown: evt
>>>        | aMorph selectors |
>>>        aMorph := self itemFromPoint: evt position.
>>>        (aMorph notNil and:[aMorph inToggleArea: (aMorph point: evt position from: self)])
>>>                ifTrue:[^self toggleExpandedState: aMorph event: evt].
>>>        evt yellowButtonPressed  "First check for option (menu) click"
>>>                ifTrue: [^ self yellowButtonActivity: evt shiftPressed].
>>>        aMorph ifNil:[^super mouseDown: evt].
>>>        aMorph highlightForMouseDown.
>>>        selectors := Array
>>>                with: #click:
>>>                with: nil
>>>                with: nil
>>>                with: (self dragEnabled ifTrue:[#startDrag:] ifFalse:[nil]).
>>> +       evt hand waitForClicksOrDrag: self event: evt selectors: selectors threshold: HandMorph dragThreshold "pixels".!
>>> -       evt hand waitForClicksOrDrag: self event: evt selectors: selectors threshold: 10 "pixels".!
>>> 
>>> Item was changed:
>>>  ----- Method: SystemWindow>>handlesMouseDown: (in category 'events') -----
>>>  handlesMouseDown: evt
>>>        "If I am not the topWindow, then I will only respond to dragging by the title bar.
>>>        Any other click will only bring me to the top"
>>> 
>>> -       (self labelRect containsPoint: evt cursorPoint)
>>> -               ifTrue: [^ true].
>>>        ^ self activeOnlyOnTop and: [self ~~ TopWindow]!
>>> 
>>> Item was changed:
>>>  ----- Method: SystemWindow>>mouseDown: (in category 'events') -----
>>>  mouseDown: evt
>>> 
>>> -       self setProperty: #clickPoint toValue: evt cursorPoint.
>>>        TopWindow == self ifFalse:
>>>                [evt hand releaseKeyboardFocus.
>>>                self activate].
>>> +
>>> +       "the window was locked, thus we got the event. re-send it now that the window is unlocked again"
>>> +       evt wasHandled: false.
>>> +       model windowActiveOnFirstClick
>>> +               ifTrue: [self processEvent: evt] "re-dispatch to any submorphs"
>>> +               ifFalse: [label processEvent: evt]. "dispatch to label so dragging works"
>>> +       evt wasHandled: true.
>>> -       model windowActiveOnFirstClick ifTrue:
>>> -               ["Normally window keeps control of first click.
>>> -               Need explicit transmission for first-click activity."
>>> -               submorphs do: [:m | (m containsPoint: evt cursorPoint) ifTrue: [m mouseDown: evt]]]
>>> -
>>>  !
>>> 
>>> Item was removed:
>>> - ----- Method: SystemWindow>>mouseMove: (in category 'events') -----
>>> - mouseMove: evt
>>> -       "Handle a mouse-move event"
>>> -
>>> -       | cp |
>>> -       cp := evt cursorPoint.
>>> -       self valueOfProperty: #clickPoint ifPresentDo:
>>> -               [:firstClick |
>>> -               ((self labelRect containsPoint: firstClick) and: [(cp dist: firstClick) > 3]) ifTrue:
>>> -               ["If this is a drag that started in the title bar, then pick me up"
>>> -               ^ self isSticky ifFalse:
>>> -                       [self fastFramingOn
>>> -                               ifTrue: [self doFastFrameDrag: firstClick]
>>> -                               ifFalse: [evt hand grabMorph: self topRendererOrSelf]]]].
>>> -       model windowActiveOnFirstClick ifTrue:
>>> -               ["Normally window takes control on first click.
>>> -               Need explicit transmission for first-click activity."
>>> -               submorphs do: [:m | (m containsPoint: cp) ifTrue: [m mouseMove: evt]]]!
>>> 
>>> Item was changed:
>>>  ----- Method: SystemWindow>>startDragFromLabel: (in category 'events') -----
>>>  startDragFromLabel: evt
>>>        "When label events are active, we need to pass dragging to the window explicitely
>>>         The window only recognizes a drag with an offset of more than 3 pixels"
>>> 
>>> +       self isSticky ifTrue: [^ self].
>>> +       self fastFramingOn
>>> +               ifTrue: [self doFastFrameDrag: evt cursorPoint]
>>> +               ifFalse: [evt hand grabMorph: self topRendererOrSelf]
>>> + !
>>> -       self setProperty: #clickPoint toValue: evt cursorPoint - 4.
>>> -       self mouseMove: evt.!
>>> 
>>> 
>>> 
>> 
>> 
>