How can my Morph reflect changes in the object it displays?
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I asked the same question on Stackoverflow (http://stackoverflow.com/questions/15534305/how-to-bind-a-labelmorph-textmorph-to-a-variable-so-that-the-morph-reflects-chan) but as i do not know how much the audiences overlap i hope you do not mind if i repeat it here:
How to bind a LabelMorph/TextMorph to a variable so that the Morph reflects changes of the variable? - I have an object with a variable containing a String. - I have a window containing a LabelMorph/TextMorph (or some other Morph that displays Text?). How do i bind the LabelMorph/TextMorph to the variable, so that the label updates when the String in the variable changes? - classic Smalltalk-80 dependent/change/update mechanism? - Pharo Announcement framework? - something different?? How would i do this? Which Morph should i use? Martin. |
Re: How can my Morph reflect changes in the object it displays?
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For this kind of situation, my solution is to use a valueHolder
instead of storing your string directly in an inst var, store it into the value holder initialize string := '' asValueHolder
string: aString string contents: aString string ^ string contents And then what you can do in your initialise is string whenChangedDo: [:newValue | self label contents: newValue ] Something like this should work ^^ The other solution (which is baaad, but can still be seen) is to have a step method refreshing the Morph. But this is really not efficient Hope it helps, Ben
On Mar 21, 2013, at 11:24 AM, MartinW <[hidden email]> wrote: I asked the same question on Stackoverflow |
Re: How can my Morph reflect changes in the object it displays?
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Ben,
But then how does this work ? | point | point := 1@2. point inspect. [ 5 seconds asDelay wait. point setX: 10 setY: 20 ] fork. You can see the inspector change its printString, without ValueHolders>>contents: being involved, just a direct instance variable assignment. Sven On 21 Mar 2013, at 11:41, Benjamin <[hidden email]> wrote: > For this kind of situation, my solution is to use a valueHolder > > instead of storing your string directly in an inst var, store it into the value holder > > initialize > string := '' asValueHolder > > string: aString > string contents: aString > > string > ^ string contents > > And then what you can do in your initialise is > > string whenChangedDo: [:newValue | self label contents: newValue ] > > Something like this should work ^^ > > > The other solution (which is baaad, but can still be seen) is to have a step method refreshing the Morph. > But this is really not efficient > > Hope it helps, > Ben > > On Mar 21, 2013, at 11:24 AM, MartinW <[hidden email]> wrote: > >> I asked the same question on Stackoverflow >> (http://stackoverflow.com/questions/15534305/how-to-bind-a-labelmorph-textmorph-to-a-variable-so-that-the-morph-reflects-chan) >> but as i do not know how much the audiences overlap i hope you do not mind >> if i repeat it here: >> >> How to bind a LabelMorph/TextMorph to a variable so that the Morph reflects >> changes of the variable? >> >> - I have an object with a variable containing a String. >> - I have a window containing a LabelMorph/TextMorph (or some other Morph >> that displays Text?). >> How do i bind the LabelMorph/TextMorph to the variable, so that the label >> updates when the String in the variable changes? >> >> - classic Smalltalk-80 dependent/change/update mechanism? >> - Pharo Announcement framework? >> - something different?? >> How would i do this? Which Morph should i use? >> >> Martin. >> >> >> >> -- >> View this message in context: http://forum.world.st/How-can-my-Morph-reflect-changes-in-the-object-it-displays-tp4677629.html >> Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. >> > |
Re: How can my Morph reflect changes in the object it displays?
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Yes, endless loop with step as far as I remember
stepAt: millisecondClockValue in: aWindow | newText | (CodeHolder smartUpdating and: [(millisecondClockValue - self timeOfLastListUpdate) > 8000]) "Not more often than once every 8 seconds" ifTrue: [self updateListsAndCodeIn: aWindow. timeOfLastListUpdate := millisecondClockValue]. newText := self contentsIsString ifTrue: [self selection] ifFalse: ["keep it short to reduce time to compute it" self selectionPrintString ]. newText = contents ifFalse: [contents := newText. self changed: #contents] stepTimeIn: aSystemWindow ^ (selectionUpdateTime ifNil: [0]) * 10 max: 1000 Tadaaa :) The old Browser was doing the same, and a lot of Morphs are doing this :s Ben On Mar 21, 2013, at 12:00 PM, Sven Van Caekenberghe <[hidden email]> wrote: Ben, |
Re: How can my Morph reflect changes in the object it displays?
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In reply to this post by MartinW
Martin Walk asked:
>How to bind a LabelMorph/TextMorph to a variable so that the Morph reflects >changes of the variable? That is a very low-level question. Do you just want to know, or do you want to use it? When building UI's in Pharo, the first question should probably be: can I get away with building it in Glamour. That is a high-level UI toolkit specialized in creating browsers. If you can, it is much less work. Stephan Eggermont |
Re: How can my Morph reflect changes in the object it displays?
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In reply to this post by Benjamin Van Ryseghem (Pharo)
On 21 Mar 2013, at 12:08, Benjamin <[hidden email]> wrote: > Yes, endless loop with step as far as I remember > > stepAt: millisecondClockValue in: aWindow > | newText | > > (CodeHolder smartUpdating and: [(millisecondClockValue - self timeOfLastListUpdate) > 8000]) "Not more often than once every 8 seconds" > ifTrue: > [self updateListsAndCodeIn: aWindow. > timeOfLastListUpdate := millisecondClockValue]. > > newText := self contentsIsString > ifTrue: [self selection] > ifFalse: ["keep it short to reduce time to compute it" > self selectionPrintString ]. > newText = contents ifFalse: > [contents := newText. > self changed: #contents] > > stepTimeIn: aSystemWindow > ^ (selectionUpdateTime ifNil: [0]) * 10 max: 1000 > > Tadaaa :) > The old Browser was doing the same, and a lot of Morphs are doing this :s Yeah ;-) Now, from the user/developer standpoint it is of course nice to have an IDE that is as close as possible to a live objects environment. For browsers, announcement are a solution. For inspectors or debuggers showing arbitrary instance variables of objects, the question of how to implement that behaviour seems like an open question. > Ben > > On Mar 21, 2013, at 12:00 PM, Sven Van Caekenberghe <[hidden email]> wrote: > >> Ben, >> >> But then how does this work ? >> >> | point | >> point := 1@2. >> point inspect. >> [ 5 seconds asDelay wait. >> point setX: 10 setY: 20 ] fork. >> >> You can see the inspector change its printString, without ValueHolders>>contents: being involved, just a direct instance variable assignment. >> >> Sven >> >> On 21 Mar 2013, at 11:41, Benjamin <[hidden email]> wrote: >> >>> For this kind of situation, my solution is to use a valueHolder >>> >>> instead of storing your string directly in an inst var, store it into the value holder >>> >>> initialize >>> string := '' asValueHolder >>> >>> string: aString >>> string contents: aString >>> >>> string >>> ^ string contents >>> >>> And then what you can do in your initialise is >>> >>> string whenChangedDo: [:newValue | self label contents: newValue ] >>> >>> Something like this should work ^^ >>> >>> >>> The other solution (which is baaad, but can still be seen) is to have a step method refreshing the Morph. >>> But this is really not efficient >>> >>> Hope it helps, >>> Ben >>> >>> On Mar 21, 2013, at 11:24 AM, MartinW <[hidden email]> wrote: >>> >>>> I asked the same question on Stackoverflow >>>> (http://stackoverflow.com/questions/15534305/how-to-bind-a-labelmorph-textmorph-to-a-variable-so-that-the-morph-reflects-chan) >>>> but as i do not know how much the audiences overlap i hope you do not mind >>>> if i repeat it here: >>>> >>>> How to bind a LabelMorph/TextMorph to a variable so that the Morph reflects >>>> changes of the variable? >>>> >>>> - I have an object with a variable containing a String. >>>> - I have a window containing a LabelMorph/TextMorph (or some other Morph >>>> that displays Text?). >>>> How do i bind the LabelMorph/TextMorph to the variable, so that the label >>>> updates when the String in the variable changes? >>>> >>>> - classic Smalltalk-80 dependent/change/update mechanism? >>>> - Pharo Announcement framework? >>>> - something different?? >>>> How would i do this? Which Morph should i use? >>>> >>>> Martin. >>>> >>>> >>>> >>>> -- >>>> View this message in context: http://forum.world.st/How-can-my-Morph-reflect-changes-in-the-object-it-displays-tp4677629.html >>>> Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. >>>> >>> >> >> > |
Re: How can my Morph reflect changes in the object it displays?
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Yes :S
The problem is mutable objects, what can you do then … For Spec I introduced value holders :) But for the basic one, it work only if you set a new value, not if what is inside the value holder mutates. I alo introduce value holders for some collections, but for the rest, I still do not know (maybe JB's handle could cover that ^^)
Ben On Mar 21, 2013, at 12:46 PM, Sven Van Caekenberghe <[hidden email]> wrote:
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In reply to this post by Stephan Eggermont-3
I am interested in both questions. I want to just use it - but of course i am interested in knowing different possibilities and how they work and why to prefer one to the other. I have not looked at Glamour yet - and i am a bit reluctant to add an extra layer, but i will give it a try. But btw - isn't it a very common problem to keep for example different views on the same object in sync? For example i want to provide a slider and a textfield for a numerical value. (I probably hoped something like Cocoa Bindings would exist.) |
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In reply to this post by Benjamin Van Ryseghem (Pharo)
I was already wondering what ValueHolders were abould :) I am looking forward to the Spec Tutorial Video from the Pharo Conference. Can i already do this with Spec: Display a Slider and a Textfield for a numerical value and when i change the value via the slider the Textfiled will update and vice versa? |
Re: How can my Morph reflect changes in the object it displays?
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Yes you can :)
(thanks to value holders ^^)
Ben On Mar 21, 2013, at 1:58 PM, MartinW <[hidden email]> wrote: Benjamin Van Ryseghem-2 wroteThe problem is mutable objects, what can you do then … |
Re: How can my Morph reflect changes in the object it displays?
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Currently doing some stuff with step and stepTime.
Are these things supported in some way in Spec? This is an open question :-) Phil 2013/3/21 Benjamin <[hidden email]>: > Yes you can :) > (thanks to value holders ^^) > > Ben > > On Mar 21, 2013, at 1:58 PM, MartinW <[hidden email]> wrote: > > Benjamin Van Ryseghem-2 wrote > > The problem is mutable objects, what can you do then … > For Spec I introduced value holders :) > > > I was already wondering what ValueHolders were abould :) > I am looking forward to the Spec Tutorial Video from the Pharo Conference. > > Can i already do this with Spec: > Display a Slider and a Textfield for a numerical value and when i change the > value via the slider the Textfiled will update and vice versa? > > > > > -- > View this message in context: > http://forum.world.st/How-can-my-Morph-reflect-changes-in-the-object-it-displays-tp4677629p4677647.html > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. > > |
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