TclOO: Can I execute a method from an object in the context ofanother object?
in [TCL]
|
Prev: TclOO: Can I execute a method from an object in the context of anotherobject?
Next: Is it possible to trap errors which reach the global scope?
From: Georgios Petasis on 12 Apr 2010 13:01 I think I have found a solution, from the "friently" objects in the wiki: http://wiki.tcl.tk/21595#pagetocf3097447 I have written a proc that returns the current style object (ELEP::Style::getStyle), and used the "forward" method: oo::class create ELEP::FlowControl::Item { forward getStyle [ELEP::Style::getStyle] initFlowControlItem .. } It seems to work. However, this is executed when the class is defined, which means that once I have created a style object, the name of this object must always be the same, even if a new style object is created. Is there a way to use a variable in forward, instead of a command? George στις 12/4/2010 19:38, O/H Georgios Petasis έγραψε: > Hi all, > > I am wondering the following: > > I have a class A. This class A has a variable named "background". > > Then, I have a class B. This class has a method (init) that sets a value > to the variable background: > > class create B { > method init {} { > my variable background > set background red > } > } > > If I have an object from class A, is there a way to execute the init > method (from a B's object) into the context of the A object? > > Why I need this? > I had a set of classes, that implement "items" on a canvas: > http://www.ellogon.org/~petasis/tcl/TkRibbon/images/Ellogon-Ribbon-System-Logs.png > > There are two major kinds of "items", a "block" and a "connector" (the > arrows). > > Right now, colours are coded inside the code (not a good approach). I am > looking for a way to "theme" these classes, where the values for a set > of variables can be retrieved from a "style" object. > > There is the alternative for the "item" object to query the value of > each variable from the style object, but many variables and a few items > (it may be slow). > > Any ideas? > > George
From: Georgios Petasis on 12 Apr 2010 13:11 Finally, it does not work :D I have connected the variables of the two objects. George στις 12/4/2010 20:01, O/H Georgios Petasis έγραψε: > I think I have found a solution, from the "friently" objects in the > wiki: http://wiki.tcl.tk/21595#pagetocf3097447 > > I have written a proc that returns the current style object > (ELEP::Style::getStyle), and used the "forward" method: > > oo::class create ELEP::FlowControl::Item { > forward getStyle [ELEP::Style::getStyle] initFlowControlItem > .. > } > > It seems to work. However, this is executed when the class is defined, > which means that once I have created a style object, the name of this > object must always be the same, even if a new style object is created. > > Is there a way to use a variable in forward, instead of a command? > > George > > > > στις 12/4/2010 19:38, O/H Georgios Petasis έγραψε: >> Hi all, >> >> I am wondering the following: >> >> I have a class A. This class A has a variable named "background". >> >> Then, I have a class B. This class has a method (init) that sets a value >> to the variable background: >> >> class create B { >> method init {} { >> my variable background >> set background red >> } >> } >> >> If I have an object from class A, is there a way to execute the init >> method (from a B's object) into the context of the A object? >> >> Why I need this? >> I had a set of classes, that implement "items" on a canvas: >> http://www.ellogon.org/~petasis/tcl/TkRibbon/images/Ellogon-Ribbon-System-Logs.png >> >> >> There are two major kinds of "items", a "block" and a "connector" (the >> arrows). >> >> Right now, colours are coded inside the code (not a good approach). I am >> looking for a way to "theme" these classes, where the values for a set >> of variables can be retrieved from a "style" object. >> >> There is the alternative for the "item" object to query the value of >> each variable from the style object, but many variables and a few items >> (it may be slow). >> >> Any ideas? >> >> George >
From: Georgios Petasis on 12 Apr 2010 13:42
I think I find a solution (a really simple one): The style object does not need to define the variables in its object. It just defines the variables in the context of the caller. class create B { method init {} { set my [uplevel namespace which my] $my variable background set background red } } So, calling anywhere in any object of A the method init from an object B does the trick. I don't know if inheritance works in style objects yet. George στις 12/4/2010 20:11, O/H Georgios Petasis έγραψε: > Finally, it does not work :D > > I have connected the variables of the two objects. > > George > > στις 12/4/2010 20:01, O/H Georgios Petasis έγραψε: >> I think I have found a solution, from the "friently" objects in the >> wiki: http://wiki.tcl.tk/21595#pagetocf3097447 >> >> I have written a proc that returns the current style object >> (ELEP::Style::getStyle), and used the "forward" method: >> >> oo::class create ELEP::FlowControl::Item { >> forward getStyle [ELEP::Style::getStyle] initFlowControlItem >> .. >> } >> >> It seems to work. However, this is executed when the class is defined, >> which means that once I have created a style object, the name of this >> object must always be the same, even if a new style object is created. >> >> Is there a way to use a variable in forward, instead of a command? >> >> George >> >> >> >> στις 12/4/2010 19:38, O/H Georgios Petasis έγραψε: >>> Hi all, >>> >>> I am wondering the following: >>> >>> I have a class A. This class A has a variable named "background". >>> >>> Then, I have a class B. This class has a method (init) that sets a value >>> to the variable background: >>> >>> class create B { >>> method init {} { >>> my variable background >>> set background red >>> } >>> } >>> >>> If I have an object from class A, is there a way to execute the init >>> method (from a B's object) into the context of the A object? >>> >>> Why I need this? >>> I had a set of classes, that implement "items" on a canvas: >>> http://www.ellogon.org/~petasis/tcl/TkRibbon/images/Ellogon-Ribbon-System-Logs.png >>> >>> >>> >>> There are two major kinds of "items", a "block" and a "connector" (the >>> arrows). >>> >>> Right now, colours are coded inside the code (not a good approach). I am >>> looking for a way to "theme" these classes, where the values for a set >>> of variables can be retrieved from a "style" object. >>> >>> There is the alternative for the "item" object to query the value of >>> each variable from the style object, but many variables and a few items >>> (it may be slow). >>> >>> Any ideas? >>> >>> George >> > |