Tony Garnock-Jones-3 wrote
> On 2016-05-20 9:19 AM, marcel.taeumel wrote:
>> Then you can do things like "if you type a y, make a z out of it and vice
>> versa": [...]
> 
> Would it be possible to have "if you type y, pretend you typed abcde"?
> 
> That is, instead of having the filter yield zero or one events (for
> refiltering??), could it yield zero or more events?
> 
> Tony

Hi Tony,

yes, I think so. You event create code is kind of awkward but I would work
like this:

...
[:event :target |
   ...
   event hand
      handleEvent: ((KeyboardEvent newFrom: event) stroke: $a);
      handleEvent: ((KeyboardEvent newFrom: event) stroke: $b);
      handleEvent: ((KeyboardEvent newFrom: event) stroke: $c);
      handleEvent: ((KeyboardEvent newFrom: event) stroke: $d);
      handleEvent: ((KeyboardEvent newFrom: event) stroke: $e).
   event wasIgnored: true.
   event].

Note that this API "(KeyboardEvent newFrom: event) stroke: $a" does not
exist at the moment. It is not that convenient to generate new events but
"event hand handleEvent: ..." should work. I have not tried this yet,
however, the event dispatching and handling code should be reentrant.

I think that I should separate upstream and downstream event filters. When
calling "ActiveHand addEventFilter: ..." it is only downstream because this
is where event processing starts. When calling "someMorphInTheWorld
addEventFilter: ..." this is rather upstream because it starts at Morph >>
#handleEvent:. Hmm... downstream event filters for any morph would be
possible in Morph >> #processEvent:using:.

Still ... I am struggling with the concept of keyboard focus and mouse
focus. There, you directly call Morph >> #handleFocusEvent:, which calls
Morph >> #handleEvent:. No bubbling up, no bubbling down. If focused morphs
want to bubble down, they have to call Morph >> #processEvent: and watch for
the #rejected pattern. See UserDialogBoxMorph >> #handleFocusEvent: for an
example. I now that this is a performance thing. If you type in a text
field, you do not want to bubble all the way down from the world. Again and
again. And again.

Best,
Marcel



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