Button tracking Morph

Hi,

Is there a way to get notified (not polling) when any mouse button/modifier
key goes up/down?

I was trying to put together a Morph (like the Mouse button indicator in the
Orange Book) that tracks up/down status of mouse buttons and modifier keys in
real time. I got stuck because all existing usage of Sensor is based on
polling while I would rather get notified on changes.

I tried stepping the following code every 175 ms:

        self color: Color lightGray.
        #(red yellow blue) do: [ :c |
                (Sensor perform: (c , 'Pressed') asSymbol) ifTrue: [
                        self color: (Color perform: c) ]
        ].

There must be better way,
TIA .. Subbu

On May 24, 2007, at 16:34 , subbukk wrote:

You should never use Sensor in Morphic, this is from MVC days.

Use Morphic events: http://wiki.squeak.org/squeak/2477

- Bert -

Have you looked at:

    HandMorph showEvents: true

found at:

http://wiki.squeak.org/squeak/2332

On 5/24/07, Bert Freudenberg <[hidden email]> wrote:

On Thursday 24 May 2007 8:07 pm, Bert Freudenberg wrote:
> You should never use Sensor in Morphic, this is from MVC days.
>
> Use Morphic events: http://wiki.squeak.org/squeak/2477

I tried the on:send:to: method, but the events get sent only when the cursor
is over the Morph. The button should be able to reflect the status of button
presses anywhere in World.

Regards .. Subbu

On May 24, 2007, at 17:58 , subbukk wrote:

See addEventListener:

- Bert -

On Thursday 24 May 2007 9:01 pm, David Mitchell wrote:
> Have you looked at:
>
>     HandMorph showEvents: true
Thanks. I noticed that HandMorph maintains a collection of listeners who get
notified on all events. I suppose I can:

ActiveHand addEventListener: self
and
ActiveHand removeEventListener: self

to turn listening on and off and then define

ButtonMorph>>handleListenEvent: evt
        "process events here"

BTW, EventStats and ShowEvents could have been implemented as listeners
instead of hacking into the handler itself. Any reason why they were done
that way?

Regards .. Subbu

On Thursday 24 May 2007 9:49 pm, subbukk wrote:
> ButtonMorph>>handleListenEvent: evt
>         "process events here"
>
> BTW, EventStats and ShowEvents could have been implemented as listeners
> instead of hacking into the handler itself. Any reason why they were done
> that way?
Well, I tried to adapt SimpleSwitchMorph by adding handleEvent:

SimpleSwitchMorph>>handleEvent: anEvent
        | modifier |
        modifier := '    '.
        anEvent anyModifierKeyPressed ifTrue: [
                anEvent commandKeyPressed ifTrue: [ modifier := 'Alt' ].
                anEvent controlKeyPressed ifTrue: [ modifier := modifier, ' Ctrl' ].
                anEvent shiftPressed ifTrue: [ modifier := modifier, ' Shift' ].
        ].
        self label: modifier.

I was able to pick a sample instance of this morph and place it in the world.
But after the first halo click, all morphs stopped responding to mouse
events :-o. Alt-. shows the system stuck in processEvents. Without Morphic
responses, I am unable to debug further.  Appending a "super handleEvent:
evt" in the end of this method doesn't solve the problem.

Any help is appreciated .. Subbu